Micro 223 Final Exam CH 19

Lower GI tract

consist of the small and large intestines, rectum, and anus.

Mumps

____ viral infection of the salivary glands

- mechanical, chemical, and physical - lysozyme; gastric juices, and bile - physical barrier - major portal of entry - mucosa-associated lymphoid tissue (MALT) - phagocytosis; lymphocytes - inflammation; adaptive immune response - lymph nodes; tonsils of the MALT system.

- A number of ____, ____, and ____ barriers limit what microbes may colonize the GI tract. - Factors like ____in saliva, the acidity of _____, and the salts in ____ kill many bacteria passing through the system. - Mucus lining the GI tract serves as a _____ that prevents many microbes from attaching to epithelial cells. - Specific cells of the digestive system aid in immune responses in the event that a pathogen takes advantage of this ______. - Lymphatic tissue is found all along the GI tract: tonsils at the back of the throat, the appendix, and Peyer's patches of the small intestine are all examples of __________ found along the GI tract. - Cells in these lymphatic tissues "sample" the environment by ______, and present their findings to ______ that may or may not need to initiate an immune response. - If response is warranted, then _____ is an early defense, followed by activation of the ______. - This is why the dr feels your neck under your jaw if you complain of a sore throat. Enlarged and inflamed _____ in the region signal a potential infection detected by _____ of the ____ system.

- single-celled eukaryotes - Giardia lamblia, Entamoeba histolytica, and Cryptosporidium species

- Protozoans are _____, ____ - The top 3 intestinal protozoans in developed countries are _____, _____, and ____.

entry portal for pathogens.

The placement of immune system tissues along the GI tract is important because its a major ___________

Picornaviridae family, Hepadnaviridae family, and Flaviviridae family

The primary cause of infectious hepatitis: Hepatitis A _____, Hepatitis B ____, and Hepatitis C ____.

16-19; dental caries (cavities); 65 years old; periodontal disease.

According to the CDC, 67% of adolescents age __-__ years old resort they have at some point had _____ and 70% of patients over ___ years old report suffering from ______ which starts as an infection of the gums and, if not treated, may progress to further inflammation and eventual erosion of the bone that surrounds the tooth. It is a leading cause of tooth loos in adults.

tonsils, appendix, and Peyer's patches

Additionally, the GI tract is associated with lymphatic tissues such as ____, ____, and ____.

- southeast, Asia, southeast and west Africa, and central and south America - 500million; Entamoeba histolytic - fecal-oral, infected, fecal-contaminated fomites - cyst and trophozoites - mucus and blood, severe abdominal cramping, and low-grade fever - Invasive disease - liver, lungs, and brain - microscopic evaluation - invasive disease; Metronidazole; paromomycin - lyse - stress

Amebiasis: - Prevelant in tropical areas like ___, ____ and ____,and _____ and ____ - ____ people harbor the causative agent: ______ - Transmission: ___ route or direct contact with anyone ____ and via ________. - Two life cycle stages: ____ and ____ - Symptoms: dysentary is characterized by profuse diarrhea containing ___ and ___, _____, and ____. - _______ may develop when trophozoites release enzymes that kill epithelial cells and cause ulcers. - If trophozoites enter the bloodstream they can cause abscesses in the ____, ____, and ____. - Diagnosis: _____- of feces for cysts or trophozoites - all infections should be treated became the protozoan can cause ______. ____ is prescribed first, followed by ____ - Trophozoites produce enzymes that _____ epithelial cells and promote invasive disease. - Cysts resist environmental ____ to aid parasite transmission

- Ascaris lumbricoides - helminthic infections - 1.2 billion - tropical and subtropical; poor sanitation - eggs; fruit and vegetables; eggs - 1. intestine; they hatch and larvae. 2. lungs where they reside for 10-14 days. 3. coughed up and swallowed and migrate to small intestine. 4. mature, mate, and feed on intestine contents. 5. intestinal wall. 6. 30cm 7. 200,000 - coughing and wheezing. asymptomatic - sever abdominal pain, malnutrition, and intestinal blockage - 2 years; feces or vomit - anus nose or mouth

Ascariasis: - caused by _____ - one of the most prevalent _____in people - infect up to ____ people worldwide - most common in _____ and ____ regions with ____- measures - Transmission: contaminated soil contains ___. Unwashed ____ and ____ are consumed which introduces ____ to the GI tract. - Life cycle: 1. eggs enter the _____, they ___ and ____ enter the bloodstream. 2. Migrate to the ____- where they reside for __-___ days. 3. larvae are _____ and _____and then they migrate to _____. 4. ____, ____, and feed on _____. 5. they do NOT attach to the _____. 6. Adult worms grow to about ___ in length. 7. adult females can produce _____ fertilized eggs per day for roughly a year - Symptoms: ___ and ___ while residing in lungs. Infections are usually ____. - High worm load can lead to _____, _____, and ____ - With progression worms can survive up to ____ in host. after they die they are passed in _____ or ____ - Diagnosis: usually occurs when the worms move out of the body through the ____, ____, or ____

- half a million; 29,000 - children, prior antibiotic therapy, and hospitalization history - HAI - nonpathogenic; pathogenic, toxin-manufacturing forms - Pseudomembranous colitis - Toxic megacolon; septic shock and die. - inflammatory response and damage the cytoskeleton; pus-filled pseudomembranous lesions - genetic variation.

C. difficile: - Every year up to _____ people develop C. difficile infections, and as many as ____ of them die. - It is also very common for _____, people who do not report ______, and people who do not have a ______. - Considered the most common ________. - People with _____ strains that don't make toxins and those colonized with ____, ______ forms, are usually protected by their normal intestinal microbiota. - Can cause ______, which is an inflammation of the colon that is accompanied by pus-filled nodules. - In extreme but rare cases, _____ may develop, which is when the large intestine can't expel gas and feces so it becomes distended and stressed; and eventually a perforation, or a tear in the colon may develop. As bacteria seep into the normally sterile abdominal cavity and cause inflammation, the patient may progress to ___and ___. - A and B toxins promote a vigorous ____ and damage the ____ of the colons epithelial cells lining, as his happens ________ develop. They eventually slough off and may occasionally be seen in the stool. - C.difficile readily acquires additional resistance mechanisms through _____.

- immune-compromised - food-handling - 1 drop - Guillain-Barré syndrome (GBS) - C. jejuni infection - tingling sensation; paralysis - hospitalized - lipopolysaccharides; neurons - paralysis

Campylobacter jejuni Causes Foodborne Illness: - In ____ patients bacteria can spread to the blood (bacteremia) which can lead to sepsis and possibly septic shock. - Using safe ____ practices can prevent infection. - ____ of raw chicken juice is enough to cause infection. - _______ C. jejune infection may trigger this autoimmune neurological disease; - 25-50% of GBS cases are preceded by a ____ infection - Weeks after diarrhea clears, ____ in legs and feet occur. eventually it advances to ____ and may spread to other body parts. - The symptoms are temporary, but individuals must be ____ - The prevailing thought is that antibodies that recognize C. jejuni's _______ cross-react with sugar on _____. - This triggers an autoimmune response against the nervous system, creating ____

- 1.6 million - isolated and sporadic infections - culprit - gram-negative, flagellated, spiral-shaped; microaerophilic - birds- chickens - poultry; raw poultry juices - mucosal layer; intestinal epithelial cells - inflammatory; diarrhea, abdominal cramps, and fever, and nausea, and vomiting

Campylobacter jejuni Causes Foodborne Illness: - Up to ____ peple in the U.S. suffer from infection every day. - It causes ____ and ____ infections - May be leading ____ of food borne illness - is a Gram-____, ____, ____-shaped bacterium that grows best in ____ conditions. - Found in intestinal tract of healthy ____- mostly ____. - Infections are primarily associated with eating undercooked ____ or cross-contaminating foods with _____. - Once ingested, the bacteria burrow through the ____- of the intestine and migrate through _____ to multiply beneath the epithelial layers - within 2-5 days, an _____ response leads to symptoms of ____, ____, and ____, ____, and ____

- Vibrio cholerae a comma-shaped Gram-negative with a single flagellum - African and southeast Asian, and areas lacking proper sanitation - hours to a few days - fecal-ora; route and human to human contact - Vaxchora - incomplete protection; longevity; proper water sanitation and hygienic food-handling practices - vomiting, profuse and watery diarrhea, and leg cramps - mucosal layer; toxin

Cholera: - caused by ____ a ____-shaped Gram-___ bacterium with a ______. - Rare in developed countries, endemic in ___ and ____ countries and in areas lacking ____ - Incubation period is ___ to _____ - Transmits via ____ route through contaminated food and water as well as via _______ contact. - _____- a single dose live vaccine is available to 18-64 year olds traveling to areas with active Cholera transmission. - The vaccine offers ____ with unknown ____; so the best prevention remains _____ and ______ - Symptoms: ____, _____ and ____, and _____ brought on by the loss of vital electrolytes. - Virulence Factor: Bacteria that survive acidity of stomach burrow past ______ of small intestines and adhere to the surface of intestinal epithelial cells. They release Cholera ___ that triggers intestinal epithelial cells to release water and ions into the intestines, generating watery diarrhea.

- bacterial culture - oral rehydration therapy; intravenous fluids; doxycycline and azithromycin - 4.3 million; 142,000 - 20 liters - decreased blood volume, hypovolemic shock, organ failure, and death - a million

Cholera: - Diagnosos is through _____ forms tool samples. - Treated with _____ for mild symptoms; _____ and antibiotics such as _____ for adults and _____ for pregnant women and children for sever cases.- Worldwide east year there are as many as ____ cases, with ____. - In severe cases up to ____ of fluid a day can be excreted - Without prompt fluid replacement, severe dehydration develops, which can lead to the cascade of ______, ______, ______, and _____. - Have to be exposed to at least a _____ bacteria for it to cause infection

- spore-forming, Gram-positive, anaerobe - elderly; antibiotic therapy - resident microbe; opportunistic pathogen - fecal-oral route, contaminated fomites, hands - individual; protective gloves and gown; antibiotic prescriptions - diarrhea, fever,abdominal pain, and nausea - Virulence Factors: ~ detergents and drugs ~ A and B toxins ~ reduces eosinophil; innate-immune - Diagnosis ~ culturing ~ glutamate dehydrogenase ~ psueudomembranous colitis - metronidazole - Rehydration therapies and vancomycin

Clostridium difficile: - is a ___-forming, Gam-____, ____ - About 75% of cases are in ___ who have had an extended stay in healthcare facility and recent _____. - May be a _______ that emerges as an ______ after antibiotics - Transmission: via ______ route, through contact with ______, or from contaminated ____. - Prevention: Isolation of infected _____ and wearing _____ and _____ for healthcare workers prevents transmission, and reducing unnecessary _______ that destroy protective gut microbiota - Symptoms: ____, ____, ___, and ____ - Virulence Factors: ~ Spore-forming bacteria that naturally resist ____ and ____. ~ releases ___ and ___ that damage the colon and induce inflammation. ~ emerging strains make a third toxin that ________ function and may suppress the ______ response - Diagnosis: ~ Diagnosed by _____ toxigenic C difficile from the patient's stool. ~ Molecular methods detect C. difficile toxin genes or actual toxins in stool, or look for _______ (an enzyme made by the bacterium) in stool. ~ Colonoscopy reveals _________. - First-line therapy for moderate cases is the antibiotic _____. ~ _____ and the antibiotic ____ are given for severe cases.

- Cryptosporidium species especially C. parvum and C. hominis - water-associated apicomplexan parasite - 65-97% - fecal-oral - 10 oocysts - diarrhea, nausea, vomiting, fever, and stomach cramps; mild diarrheal; immunocompromised - sporozoites; multiply; inflammatory; asexual reproduction and later sexual reproduction; macrogametes; microgametes; Microgametes fertilizing macrogametes produces oocysts; feces - chronic infection - water treatment, chlorine; water filters; boiling; - filtration and UV radiation - Treatment: Nitazoxanide - microscopic evaluation

Cryptosporidiosis: - Caused by ______, especially ____ and ____ - Is a ____ _____parasite - It naturally resides in the ____ of humans and animals, particularly ____. - __-__% of US surface water contains Cryptosporidium oocysts - Transmission: ___ route - As few as _____ needed to cause infection - Symptoms: ____, ____, ____, ____, and ____ most show ______ symptoms for 1-2 weeks. Infections of ________ can lead to more serious diarrhea. - Oocysts enter the intestines and release _____ which attach to epithelial cells and ____. This elicits an _____ response and parasites undergo _____ and later _____. Then _____ are produced which are female and ____ which are males. The process of _____ fertilizing _____ produces ____. and Ocysts are excreted in ____. - Complications: immunocompromised can have _____ that may lead to death - Prevention: proper _____, _____ alone is no sufficient. ____ can remove oocysts while ____ deactivates them. Water should be Treated by using ____ and ____-. - Treatment: ____- is prescribed former sever infections or for immune-compromised patients. - Diagnosis: _____ of stool for oocysts or detecting antigens

- normal microbiota - Streptococcus and Actinomyces species - Viellonella and Haemophilus; dental plague - plague - Streptococcus mutans in plague biofilms

Dental Caries (Cavities): - In babies, the oral _____ becomes established very soon after birth through exposure to bacteria from caregivers and feedings. - ____ and ____ species are among the first to begin attaching to the tooth enamel. - Other bacterial genera such as ____ and ____ may attach next, creating the complex biofilm called _____. - The presence of _____ promotes tooth decay because it holds resident bacteria close to the tooth enamel. - A bacteria, especially _____ in ______, metabolize sugars, they create acids that can eat away at the enamel to cause dental carries

- hardens teeth and promotes mineralization - 25% - discoloration, tooth sensitivity, and pain - X-rays - porcelain crown - root canal

Dental Caries: - Fluoride _____ and promotes_____ making them less susceptible to decay. - The American dental association, which conducts surveys on the effectiveness of fluoridated water, states that tooth decay has been reduced in ____% of the American population due to fluoridated water. Signs and Symptoms: small ____ may be visible, _____, and mild to severe ____ develops as the cavity progresses deeper into the tooth - Diagnosis: ____ reveal white areas where caries exist. - Extensive decay may require replacing the top of a tooth with a _____. - If infection reaches the inner tooth, a ____ drills out the pulp and replaces it with filling.

- brushing teeth twice daily and flossing; bacterial growth; bacteria - tartar (or calculus) - twice-yearly - Sealants - dietary sugars - fluoride

Dental Caries: - _______ and _____ will physically remove superficial plague layers. However, _____ within the deeper biofilm layers and new _____ entering the mouth quickly reestablish what was removed. - Also,when plague calcifies into _____, it must be scraped off the teeth. - Dentists recommend a _____ dental cleaning and checkup to limit carries and periodontal disease. - ____ are another preventative measure that involves plastic coatings that cover crevices finback teeth where plague could grow. - Limiting ______ reduces lactic acid production by the bacteria in dental plague and decreases the risk for dental caries. - In the U.S. federal guidelines recommend addition of _____ to community water systems; this ion is also added to many toothpaste and mouthwashes.

- dentin - pulp - abscess or pus-filled lesion - resin composite or amalgam - removal of the entire tooth. - gums and in tooth crevices prevents salivary enzymes

Dental Caries: - As enamel erodes, the underlying ____ is exposed/damaged. - Eventually, if the cavity is not filled, the ____, where blood vessels and nerves are located, can become infected. - Infection can then generate an ____ or _____, in the surrounding gum or at the root of the tooth. - Dentists repair cavities by cleaning out the affected area ( frequently requiring drilling) and then filling the hole with _____ or _____. - Severe cases may require _________ - Plague's dense, mat-like structure along the ____ and in tooth _____ prevents _____ from penetrating to the layers of bacteria that lie against the tooth enamel.

- upper GI endoscopy - endoscope; esophagus, stomach, and small intestine - Lower endoscopy (colonoscopy); rectum an large intestine - Clostridium difficile-associated dysentery

Diagnostic Tools: - Tissue damage, such as ulcers or inflammation, can be assessed using an _______, but this diagnostic tool won't reveal the precise microbe responsible. - During this procedure an _____, a long flexible tube with a light and lens attached o the end, is inserted in the mouth and used to view the _____, _____, and _____. - A ______ involves a colonoscope, which resembles an endoscope and is inserted into the anus and is used to view the _____ and _____. - Large patches of mucous membranes sloughing off can provide immediate diagnosis for disease such as __________, but again, this technique can't confirm the specific microbial agent.

- fecal samples - eosin methylene blue and MacConkey agar - E. coli O157 strains - cefixime and tellurite - commensal E. coli strain

Diagnostic Tools: - When a patient presents with intestinal symptoms, _____ are usually collected in an attempt to identify the causative agent. - From the clinical microbiology lab perspective, a diverse collection of selective and differential culture media, such as _____ and _____ are used to detect GI bacterial pathogens. - _____ can be cultured using sorbitol-MacConkey agar. - Often SMAC agar is supplemented with an antibiotic called ______ and an oxide mineral called ______. - These additives allow for the specific pathogen ______ strain to grow and be identified while preventing the growth of ______ and other harmless GI bacteria that are commonly present in feces.

- bacterial culture; antigens on a pathogen or charcaterize pathogen genes - C. difficile, Shiga toxin-producing E. coli, and certain Campylobacter species - parasites or their eggs.

Diagnostic Tools: - _____ is the most common tool for pathogen identification, but specialized molecular tests that detect ____ on a pathogen or characterize _______ are also occasionally used. - These molecular techniques tend to be used to detect _____, ________, and certain _______ species. - Furthermore, microscopic examination of stool samples may identify _____ or _____.

- digesting food and providing nutrients - Escherichia coli. - metabolism and obesity; depression and diabetes; train and modulate immune responses

Digestive System Microbiome: - In addition to warding off pathogens, normal gut microbiota assist in ______ and providing _____ for the body. - An important source of vitamin K in the intestine comes from ________. - In addition to making vitamins and competing with pathogens, research reveals there is a complex association between our gut microbiota and our health. Our GI microbiota may impact ____- and ____; affect the development of _____ and diseases such as _____; and ____ and _____ immune responses.

- microbes - Streptococcus species - Streptococcus, Neisseria, Fusobacterium, and Actinomyces species - Bacteriodes species - Candida; protozoa - health and in disease - taking up surface space - surrounding nutrients and excrete antimicrobial products

Digestive System Microbiome: - The digestive system is home to the most diverse and densely populated collection of _____ in the body. - Examples of the most common residents in the mouth and on the tongue and gums are _____ species. - The teeth are mainly colonized by a variety of ____, _____, _____, and _____ species. - Stool is rich in _____ species - Fungi such as _____ and a few _____ also live in the digestive tract. - These normal gut microbiota have essential roles in both our _____ and in _____. - Resident bacteria can prevent pathogenic bacteria from settling into areas oof the intestine by simply ________ that would otherwise be available for potential colonization. - They also compete for ______ and excrete ______ to kill off contending newcomers.

- crustaceans, fish, and mammals 1. mammalian host 2. freshwater 3. ciliated embryos 4. crustaceans 5. first larval stage 6. fish 7. flesh 8. larval cysts 9. infected fish 10. immature worm 11. intestinal wall 12. adult worm 13. eggs 14. 1-15 meters

Diphyllobothrium datum (fish tapeworm) - Requires 3 hosts:___, ___, and ____ - Life cycle: 1. Eggs are defecated by a ____ host. 2. Enter into ____. 3. Become ____. 4. _____ eat the embryo. 5. Embryo matures into _____. 6. ____ eat the infected crustacean. 7. parasite migrates into the fish's ____. 8. Forms ____. 9. humans consume ____. 10. larva becomes an ___. 11. attaches to the ____. 12. matures into an ____. 13. mature worm releases ____ after 6 weeks. 14. worm grows between __-___ in length.

- E. coli O157: H7, Gram-negative, motile rods - normla microbiota - nonpathogenic - shiva toxin - virulence factors; pathotypes - pathotypes - diarrhea; UTI, bacteremia, and meningitis; fecal-oral route; fever and/or dysentery - specific symptoms, disease severity and length, and treatment.

E. coli - Causative agent: ______, Gram-____ bacterium, _____, _____-shaped. - Most common _____ in mammalian intestines - Most strains are ____ - some strains produce ____ - Pathogenic strains are characterized based on their _____ and are grouped into _____. - E. coli ____ can be grouped by their O and H antigens -There are 6 main pathotypes that cause ____, and other patotypes that cause _____, ____, and ____. All transmitted the ___ route. Some may also cause ___ and/or ___ - Patotypes determine: _____, ________, and ____.

- hamburgers, unpasteurized juices, and petting zoo - dysentery-associated - healthy cattle - removed - dairy and juice products - 10 -100 - abdominal pain, watery diarrhea, bloody diarrhea, low-grade fever - a week; hemolytic uremic syndrome - children, elderly, and immune-compromised

E. coli O157: H7 - Deadly outbreaks associated with ____, _____, and ____. - Most common ______ serovar in the US - Its presence in the normal microbiota of _____ is the main way it gets into humans. - If intestines are not sufficiently _____ before meat is ground up, meat can be contaminated. - ____ and ____ can harbor the agent. - Ingesting ___ to ___ bacterial cels may be sufficient because it is resistant to gastric acids - Symptoms: ____ and _____, ____, ____. - Typically resolves within ___ in up to 10% of cases it progresses to _______. - ____, ____, and ____ patients are at the greatest risk for developing HUS.

- exotoxins; diarrhea and abdominal pain - enterotoxins; emetic - multiply; toxins - bacteria; toxins - Staphylococcus aureus, Clostridium perfringens, and Bacillus cereus. - S. aureus - C. perfringens and B. cereus

Food Poisoning: - Symptoms triggered by ingested _____ that inflame intestinal cells and prevent water from absorbing into the intestine, causing ____ and ____. - Toxins that target intestines are called ____ and can also be ____ (tigger vomit) - Leaving foods out at room temp for too long can allow bacteria on food to ____ and release ____ causing food poisoning. - Heat , cooking or reheating the food may kill the ____- but does not destroy/affect the ____. - Bacterial pathogens _____, _____, and ____ are leading causes of food poisoning. - ____ food poisoning often linked creamy salads and dairy based foods. - ____ and ____ are both spore-forming.

- C. perfringens - B. cereus - Botulism - toxin-producing fungi; Aspergillus flavus toxin - 30 min to 6 hours - nausea and vomiting - 24 hours or 7 days

Food Poisoning: - ____ is commonly found in animal intestines and on raw meat. Its food poisoning cases are linked to gravy and meat products left out at room temp for too long. - ____ is in soil and can contaminate produce, meat, fish, milk products, and starchy foos such as rice, potatoes, or pasta - Cooking does not always kill its spores, so spores become actively growing bacteria and produce ____. - _____ is another type of food poisoning from the spore forming clostridium botulinum. This exotoxin enters the blood and targets nerves - _______ that grow on crops. Corn and peanuts must be treated to remove the ______, aflatoxin. Meat, eggs, and milk may become contaminated with alfaltoxin due to animals ingesting contaminated feed. - Symptom Onset: ___ to ___ after exposure - Symptoms: ____, ___ - Recovery: within ___or ___ in severe cases.

- GI tract - diarrhea - pathogen - Campylobacter jejune, Shigella species, E. coli, Salmonella species, and Listeria monocytogenes - 1-5 days - fever, headache, muscle aches, nausea, diarrhea, and abdominal pain - days to weeks

Foodborne Bacterial Infections: - are the result of ingesting food that harbors live bacterial pathogens that infect the _____. - Most common symptom is ____. - Severity depends type of ____ that causes infection. - most common causative agents are ____, ____, ____, ____, and ____ - Symptom onset: __-__ days after exposure - Signs and Symptoms: ___, ___, ____, ____, ____, and ____ - Recovery: ____ to ____

- 1 in 6 - Norovirus - fecal contamination - Foodborne infection and Food poisoning (aka food intoxication)

Foodborne Illnesses: - The CDC estimates that each year ___ in ___ Americans suffers from a food borne illness. - Of the 31 characterized pathogens that are known to cause food borne illness, _____ is the most common causative agent. - Majority of food borne illnesses are due to _____ of food or water. - Foodborne illnesses can be sorted into two categories, _____ and _____, both of which are entirely preventable

- fecal-oral route - food or water - hand washing, sewer management, water sanitation practices, and food processing/handlings regulations - food borne illness - poor water sanitation and limited food-handling regulations - diarrhea and and dysentery

GI Infection Symptoms and Diagnostic Tools: - Most intestinal pathogens that cause diarrhea or dysentery transmit via the ______ route- meaning pathogens duns in feces are ingested. - The most common means of this route of transmission is contaminated ____ or ____. - All of us are exposed to some degree of this contamination in our daily lives. - ____, ____, ____, and ____ all help limit this route of transmission. - The CDC estimates about 1in 6 Americans will suffer from a _____ each year. - In developing nations ______ and limited _______ make illnesses caused by this route of transmission even more prevalent. - Worldwide _____ and _____ oil about 2.2 million people each year- with the majority of deaths occurring in children under 5 years old who live in developing nations.

- fluid in the stool and bleeding - Dysentery - water and electrolyte loss (dehydration); hypovolemic shock

GI Infection Symptoms and Diagnostic Tools: - destruction of infected intestinal cells may also lead to excess ____ in the _____ and _____. - _____- may develop in sever cases of gastroenteritis; it is similar to diarrhea but painful, and typically characterized by blood and mucus in stool. - Both diarrhea and dysentery can lead to excessive _____ and ____ loss, which can cause potentially deadly ______ as organs begin to shut down due to lowered blood pressure.

- abdominal pain and loose stools that may contain blood or mucus - fever and/or vomiting - diarrhea - enteritis - Gastritis - gastroenteritis

GI Infection Symptoms and Diagnostic Tools: A huge variety of pathogens invade the digestive tract, but the symptoms of the infections they cause are very similar. - They include _____ and loose stools that may contain ____ or _____. - In addition, there may be _____, and/or _____. - _____ is described as a loose or watery stool - When a pathogen infects the intestinal lining, an inflammatory response called _____ develops - In _____ the stomach is inflamed. - Inflammation of both the stomach and intestines is called ________. - _____ also commonly develops because pain is a cardinal sign of inflammation.

- Rod shaped, Gram-negative bacterium Helicobacter pylori - microaerophilic; suffer symptoms - belching, vomiting, abdominal pain due to gastritis, and stools tinged with blood - fecal-oral route - stomach lining; stomach - asthma and acid reflux

Gastritis and Somach Ulcers: - Caused by ___shaped, Gram-___ bacterium ____. - According to the CDC, at any given time the _____ bacteria infects 2/3rds of the worlds population, although many never ______. - When symptoms develop, they may include _____, ____, ____ due to gastritis, and ___ tinged with ____ from bleeding stomach ulcers. - Transmission is via _____ route. the bacteria can also be found in the ____, so direct contact may also transmit. - Ulcers form in areas where the _____ is damaged by the bacterium and the host host inflammatory response. On the other hand, some benefits to the bacterium colonization of the ___ have emerged - A few studies suggest that conditions such as ____ and ____ are reduced by the presence of the bacterium.

- Giardia lamblia - 2%; 6-8% - intestinal parasite - untreated water; person - 1-2 weeks - fecal-oral route, fomites, direct contact - rivers or lakes - person to person or animal to person - 10 cysts - cyst and trophozoites - tough cyst - small intestine; trophozoites - adhesion disc - asexually - colon and enter cyst stage - cysts and trophozoites; cysts - diarrhea, gas, abdominal pain, nausea, vomiting; nutrient malabsorption - microscopic evaluation; molecular methods - supportive therapy and drugs, metronidazole and nitazoxanide

Giardiasis: - Caused by _____ - This protozoan infects intestines of about ___% of adults and ___-___% of children in developed countries. - Most common _____ in US - Anyone who drinks ____ or has close contact with an infected ____ is at risk - Incubation: __-__ weeks. - Transmission: ____ route contaminated ____, or from _____ with infected patient. - Hikers who drink from ____ or rivers - can be transmitted from _____ or _____. - Ingesting as few as ____ can cause infection. - Two life cycle stages: ____ and ____- Outside the host Giardia exists as a ____form that resists chlorine disinfection, UV light, and freezing - In the _____ the cyst hatches to release two _____. - Uses _____to attach to epithelial cells of the small intestines and leeches off the host. - Next, the trophozoites reproduce ____. - Some then progress to the ____ and enter the ____. - Both ____- and _____ are expelled in feces but only _____ survives - Symptoms: _____, ____, _____, ____, ____. Chronic infections can cause ______. - Diagnosis: diagnosed via ______ of feces for cysts or trophozoites. Also _____ to detect Giardia antigens. - Treatment: _____ and ____, _____ or _____ for severe infections

- multicellular - naked eye - microscopic egg or larvae in either soil or water - round worms or flat worms

Helminths: - _____ animals - In their adult form they can often be seen with the ____ - Usually transmitted as _____ or ____ in either ____ or ____ - Either _____ or _____ (tapeworms and flukes)

- inflammation; bilirubin - Bilirubin; regularly; hepatitis infection - bilirubin; liver function; bilirubin - outside a host's body; high temperature - 2 weeks - self-limiting; a few weeks - liver condition

Hepatitis A: - As hepatocytes become infected, _____ develops an impacts normal liver functions, including limiting the clearing of ____ from the blood. - _____, a yellow-tinted substance, is a natural by-product of red blood cell breakdown- a normal physiological process that occurs _____, not just during a ______. - As ____ accumulates in the bloodstream it causes a yellowing of the skin and sclera.When _____ is restored and ____ is cleared, this yellowing resolves. - The virus is fairly stable and can remain infectious for months __________; however, its readily inactivated by _____. - Another factor contributing to HAV spread is that viral particles are most concentrated in the feces ____ before symptoms develop, allowing for someone to unknowingly spread the infection. - Severe manifestations are rare, and usually HAV infections are _____ and resolve within _____ without drug therapies. - For those with a preexisting ______, a hepatitis A infection can be severe and even life threatening.

- non enveloped, single-stranded, RNA genome virus from the Picornaviridae family. - food borne and waterborne - vaccine - fecal-oral route - Unvaccinated - 6 - 70%; low-grade fever, nausea, vomitng, loss of appetite, joint pain, abdominal pain, and fatigue; clay-colored feces and jaundice

Hepatitis A: - Caused by a Hepatitis A virus (HAV) which is a ______, ____-stranded ____ genome virus from the _____ family - AKA _____and _____ hepatitis. - The infection rates in the U.S. decreased dramatically since a ____ was introduced in 1995. - The virus is typically spread by the _____, so infected restaurant workers who fail to wash up after using the bathroom may contribute to an outbreak. - _____ individuals who travel to countries where HAV is common are at the greatest risk for infection. - Most children under age ___ will have an asymptomatic infection. - Patients older than 6 have about a ____% chance of developing signs and symptoms such as ____, ____, ____, ____, ____, ____, and ____ - Diagnostic symptoms include _____ and ____ which presents as a yellowing of the skin and of the sclera (whites of the eyes).

- 15-50 days; 28 days - Virulence Factors: ~ interferon response ~ cloaks itself; antibody - Chronic infections - HAV antibodies - rest, proper nutrition, and fluids - Antibodies

Hepatitis A: - Incubation period of __ to ___ days, with a average of ___ days - Virulence Factors: ~ Inhibits host ____ response ~ The virus ___ itself with host cell membrane to avoid ____ detection as it circulates in the blood. - No ________ - Diagnosis: Blood tests detect _______. - Treatment includes ___, ___, and ___. - ____ given within 2 weeks of primary exposure can sometimes limit infection.

- intestinal cells - viremia; liver cells (hepatocytes)

Hepatitis A: - Once ingested.HAV multiplies within _____. - From there the virions enter the bloodstream, a situation called _____ and eventually they infect ______ (_____).

- acute - 6; chronic - 5; chronically infected - cirrhosis; liver failure - hepatocellular carcinoma

Hepatitis B: - For most patients, the virus causes ____ infection and clears within weeks. - However, in up to 10% of patients age ___ and up the virus is not cleared and it establishes a _____ infection. - Children under age ____ are far more likely to become _____ infected than adults. - Over time, with intermittent inflammation, ______(scarring of the liver) occurs and eventually leads to ____. - HBV can also induce ______, a form liver cancer.

- vaccine, condom usage, and by not sharing needles - Virulence Factors: ~ liver cells; acute infections ~ chronic infections; T cytotoxic cells ~ 7 days - 1; 1-5; 6 and older - HBV viral DNA, surface antigens, or antibodies - rest, propelling nutrition, and fluids - chronic cases

Hepatitis B: - Spread of infectious can be prevented with ____, _____, and by not _____. - Virulence Factors: ~ Protein secreted from infected ____ helps the virus evade immune detection in _____ infections. ~ In _____ infections, _____ attack infected hepatocytes, causing cirrhosis. ~ the virus can survive outside of the host's body for up to ___. - Chronic infections develop in 90% of those under age ___; up to 50% in ages __ to __; and up to 10% in ages ___ and older. - Blood tests detect HBV ____, _____, or ____. - Treatment includes ____, ____, and ____. - For _____ cases, antivirals can reduce viral load and help to clear infections.

- placenta - 12 hours; HBV vaccine; HBIG (hepatitis B immune globulin) - breast milk of infected mothers - 45-160 day; 120 days; low-grade fever, nausea, vomitng, loss of appetite, joint pain, abdominal pain, and fatigue; clay-colored feces and jaundice - 50%

Hepatitis B: - While HBV does not cross the _____, vertical transmission from an infected mother to her baby can still occur during delivery. - If the mother is infected, then within _____ of birth, the baby is given the _____ and an antibody preparation called _____ that reduces the chance of he baby becoming infected. - Although HBV is found in ____, it has not been shown to transmit the virus (this was true even before immune prophylaxis options were available) - There is a ___ to ___ day viral incubation with an average of _____ before symptoms develop including ____, ____, ____, ____, ____, ____, and ____; Diagnostic symptoms include _____ and ____. - About ___% of cases are asymptomatic

- enveloped, double-stranded DNA genome, from the Hepadnaviridae family - acute and chronic - HBV vaccinations - chronic HBV; 800,00- 2.2 million - direct contact with bodily fluids or open sores; sexual contact; needles, razors, or toothbrush - Accidental percutaneous

Hepatitis B: - caused by a Hepatitis B virus (HBV) which is _____, ____-stranded ___ genome, from the _____ family - Causes ____ and ____ infections - since 1991 _____ have dramatically reduced infections by about 82%. - As of 2016 ____ HBV still affects an estimated ____ to ____ people living in the U.S. - Transmission usually occurs through _____ with ____ or ____ from an infected individual- ____ with an infected parter, sharing HBV-contaminated ____, ____, or ____ can lead to infection. - ________ (through skin): exposures due to needle sticks or cuts from HBV contaminated sharps are responsible for the higher incidence among healthcare workers.

- enveloped, single-stranded, RNA genome, from the Flaviviridae family. - silent killer - 3.2 million - chronic infection, when liver damage develops - 1989; sensitive HCV detection - pathogen - shared needles; blood and bodily fluids - vertical transmission; placenta

Hepatitis C: - Caused by a Hepatitis C virus (HCV) which is ____, ____-stranded, ____ genome, from the ____ family - AKA the _____ - As of 2016, about _____ Americans are infected with HCV. - However, the number of infections is difficult to accurately estimate because most people don't even know they have the virus until the later stages of a ______, when _____ develops -The virus wasn't characterized until ____, and it wasn't until _______ became available in 1992 that transmission via blood transfusions became rare. - After that point, donated blood was screened for the _____ before being used. - Today, most HCV cases are associated with ______, although some cases develop following direct contact with ____ and ____ from an HCV-infected patient. - _____ from mother to child is also possible. The virus has been shown to cross the _____.

- chronic bloodborne - 14-180 days; 45 days - condom use and not sharing needles -low-grade fever, nausea, vomitng, loss of appetite, joint pain, abdominal pain, and fatigue; clay-colored feces and jaundice - antibodies and surface antigens - Havoni, Dalinza, and Epclusa

Hepatitis C: - Is the most common ________ infection in the U.S. - Has an incubation period of __-__ days with an average of ___ days - No vaccine so prevention involves ____ and not _____. - Signs and symptoms: ____, ____, ____, ____, ____, ____, and ____; Diagnostic symptoms include _____ and ____. - Diagnosis: Blood tests detect HCV _____ and _____. - Most cases are now curable with antivirals such as _____, _____, and _____.

- approved drug; vaccine - breast milk of infected mothers - mutates; vaccine - chronic form - chronic; liver problems; acute infection

Hepatitis C: - The absence of an _____ for use during pregnancy combined with the lack of a _____, make it currently impossible to prevent vertical transmission - Like HBV, HCV can be found in ______, but has not been shown to cause infection. - HCV continually ____, making it difficult for the immune system to recognize and even harder for an effective ____ to be developed. - Approximately 75-85% of HCV patients develop a _____ form of the infection. - Early infection with HCV is usually asymptomatic and _____ infections are not usually diagnosed until ____ problems begin- often years after initial _____ infection.

- liver cancer and cirrhosis; 90% - protease and polymerase - cirrhosis and liver cancer - 20% - liver - HAV and HBV vaccine

Hepatitis C: - ____ and ____ are complications of chronic infection. Newer drug treatment can cure ___% of those infected. - Treatments consist of ____, ____, another viral protein inhibitor medications. - While side effects from these medication can be sever, they are clearly preferable to ____ and____. - The CDC estimates that up to ____% of infected individuals spontaneously clergies the virus without treatment. - If the body cannot clear the virus, then repeated immune responses will eventually damage the ____. - The combined ___ and ___ is recommended for those with HCV in order to avoid confection andgmreater viral load in the liver.

- enveloped, single-stranded RNA genome, with no family designation - developing nations. - HBV - HBV infection as a "confection"; "superinfection". - HBV patients

Hepatitis D: - Caused by a Hepatitis D virus which is _____, ____-stranded, ____ genome with ______. - Infections are rare in the U.S., but are a serious concern in many _____. - HDV infections cannot occur without ___ being present - HDV infection can either occur simultaneously with ____ infection as a "_____". Or it can occur as a "_____" in which the patient have ____ and then later contracts HDV in addition. - Patients with these type of infection tend to exhibit more severe symptoms than ____ patients.

- 45-160 days; 90 days - bloodborne; sexual and vertical transmission - HBV vaccine - condom use and not sharing needles. - low-grade fever, nausea, vomitng, loss of appetite, joint pain, abdominal pain, and fatigue; clay-colored feces and jaundice - liver cells; HBV replication machinery - antibodies or antigens; Reverse transcription polymerase chain reaction (RT-PCR) - antiviral therapies - vaccines

Hepatitis D: - Incubation period is __-__ days with an average of ___ days. - Transmission: primarily ____ transmission but ____ and ____ are also possible. - Since HDV requires HBV to cause infection, _____ protects against HDV too. - Spread can also be prevented by _____ and not _____. - Both ___ and ___ infections can occur - Signs and Symptoms:____, ____, ____, ____, ____, ____, and ____; Diagnostic symptoms include _____ and ____. - Virulence Factors: Enters the blood and targets ____ for replication; requires _______ to replicate - Diagnosis: Blood tests detect HDV ____ or ____. ______ is used to detect HDV viral RNA. - Treated with _______ (ribavirij or interferon) - There are no ____ currently avillabe in the U.S. for HDV

- non enveloped, single-stranded, RNA genome, from the Hepeviridae family - fecal-oral; undercooked meat or shellfish - poor sanitation and lack of clean drinking water - 20 million; 3.3 million - 56,000; inconsequential - vaccines

Hepatitis E: - Caused by a Hepatitis E virus which is ____, ____-stranded, ____ genome, from the ____ family - HEV primarily has a _____ transmission. In some cases HEV outbreaks have been linked to eating _____ and ____ from endemic areas. - Countries with ____ and lack _____ have higher incidences of HEV infections. - HEV is estimated to infect about _____ people per year, with about _____ million of those cases being accompanied by symptoms. - About ____people die each year of HEV-associated complications- so its ______. - There are no ____ currently avillabe in the U.S. for HEV

- poor sewer and water management/sanitation - 2-10 weeks; 5-6 weeks - acute and chronic - low-grade fever, nausea, vomitng, loss of appetite, joint pain, abdominal pain, and fatigue; clay-colored feces and jaundice - liver cells - antibodies; Reverse transcription polymerase chain reaction (RT-PCR) - antiviral therapies

Hepatits E: - Found worldwide, but more prevalent in areas with ____ and ____/____, such as south and east Asia. - Incubation is __-__ weeks with an average of __-__ weeks. - Both ____ and ____ infections occur - Signs and Symptoms:____, ____, ____, ____, ____, ____, and ____; Diagnostic symptoms include _____ and ____. - Virulence Factors: Enters the blood and targets ____ for replication. - Diagnosis: Blood tests detect HEV _____. _____ is used to detect HEV RNA in blood or stool samples. - Treated with _______ (ribavirij or interferon)

- soil-transmitted - 500,000,000 - human feces - hatch - adult worms - bare feet and legs - bloodstream - lungs, coughed up - intestines - intestinal wall - mature and mate - fertilized eggs - Symptoms: iron and nutrient; growth of children - sewage management and shoes

Hookworm (Necator amricaanus): - _____ roundworms - ____worldide are infected - Transmission: soil is contaminated with _____, harboring eggs - eggs ___ - mature into ___ - burrow into ___ and ____ - larvae enter the ____ - migrate to ____, where they are _____ and then swallowed - enter the ____ - attach to the ____ - ___ and ___ - Release _____. - Symptoms: heavy worm load leads to ____ and ____ deficiencies and impairs ____ of ____. - Prevention: proper ___to reduce human feces in the soil and wear ____

- 2 inches - dwarf tapeworms - tapeworm infections - fecal-oral - arthropods - asymptomatic - diarrhea, nausea, and loss of appetite - heavy worm loads

Hymenolepis nana: - less than ___- long - AKA ____ - worldwide distribution - most common cause of _____ in humans - _____ route of transmission when the worms eggs are ingested - Accidental ingestion of infected ______ such as fleas - Symptoms: light worm loads are _____ but can last for years - Heavy worm loads may lead to ____, ___, and ____ - If progresses, Eggs can hatch inside the same host leading to ______.

- gallbladder - liver; galbladder - Gram-positive - pancreas - nutrients; drugs and toxins; small intestine - bilirubin - water and water soluble vitamins - rectum; anus as feces.

Lower GI Tract: - As chyme enters the small intestine, the _______ secretes bile to help aid in fat digestion. - Bile is a green-yellow fluid made by the ____ and then concentrated and stored in the _____. - The salts in bile inhibit the growth of many bacteria, especially ______ bacteria. - The _____ also secretes substances to aid in digestion. - The liver, which stores certain _____ and metabolizes most ____ and ____, directly receives nutrient-rich blood from vessels of the _____. - The liver removes substances like ______, a by-product of red blood cell breakdown. - Whatever is not absorbed in the small intestine makes its way to the large intestine, where most of our ______ and ______ are absorbed. - Any undigested matter remains in the _____ until excreted through the _____ as _____.

- envelops, single-stranded RNA genome, from the Parayxoviridae family - Africa, Southern Asia, and the Middle East - 2 doses - parotid salivary glands; V protein - Meningitis and orchitis - reverse transcription polymerase chain reaction; IgM antibodies - ibuprofen

Mumps: - Caused by an _____, ____-stranded _____ genome from the _____ family. - Endemic in areas with low MMR vaccination rates such as _____, _____, and the _____. - Can be prevented with ___ doses of MMR vaccine - Virulence Factors: Targets the _______; The virus utilizes a _____ to block interferon and interleukin signaling within the host cell. - Complications include _____ and ____ (inflammation of the testes) that can lead to sterility - Usually _______ is performed saliva samples; blood may also be assessed to detect _____ to the mumps virus. - Nonsteriodal anti-inflammatory drugs such as ______ manage fever and parotid gland swelling

- stomach to severe diarrhea and dehydration - MMR vaccine - immunized; mumps is endemic - RNA; infected saliva - nose or mouth - bloodstream to infect salivary glands, particularly the parotid glands - 2-3 weeks; dry mouth, fever, headache, and fatigue - parotid gland, termed parotitis - saliva

Mumps: - Viral digestive tract infections can range in symptoms from mild upset _____ to severe _____ and ____. - Today's extremely rare in developed countries because of the ______. - Usually infections only arise in people who are not_____ and travel outside the U.S. to areas where _______. - Mumps is an ____ virus that spreads among humans through _____. - When the mumps virus enters the ___ or ____ it quickly replicates in the upper respiratory tract. - Thereafter, the virus enters the ______ to infect _____, particularly the ______. - The incubation period of ___ to ___ weeks is often followed by ____, ____, ____, and ____. - Subsequent swellings under the jaw is due to inflammation of the _____, termed ____. - Because the virus is released in ____ almost a week before symptoms develop, preventing spread to others can be difficult.

- immunity to the next norovirus - profuse vomiting and diarrhea - Young, elderly, and immunocompromised - Microvilli - Reverse transcription polymerase chain reaction (RT-PCR) - oral rehydration therapies; intravenous fluids

Norovirus: - There are many types of norovirus, and new strains arise every few years. Thus, suffering through a bout of norovirus will usually not provide _________. - The illness induces ____ and ____ that early contaminate surfaces and make it hard to limit disease transmission - ____, ____, and ____ people are at risk for moderate to severe dehydration - Virulence Factors: virus-infected cell of ____ undergo cell death. - ________ detects RNA ins tool or vomit samples. - Treated with ______, or in cases of moderate to severe dehydration, _____

- acute viral gastroenteritis - long-term care facilities - non enveloped, single-stranded RNA genome, from the Caliciviridae family; 20 particles - feces and vomit; fecal-oral route - 12-48; 3 days or more -Acute diarrhea and projectile vomiting - a few days - dehydrated, have blood in their stool, and/or experience excessive vomiting; low-grade fever and malaise

Norovirus: - the leading cause of ________ in the U.S. - Over half of all outbreaks occur in ______. - The _____, ___-stranded, ____ genome, from the ____ family is very contagious, as only ____ are required for infection. - ___ and ___ serve to spread the virus via a ____ route. - Symptoms develop within __ to __ hours of ingesting the virus. and the virus can last for ___ days or more. Others include, _____ and ____ - ____ lasting 36-72 hours and ____ can be alarming symptoms. - Most healthy individual fully recover within _____ without medical intervention. - However, patients that become ____, have ____ in their ____, and/or experience _____ that makes oral rehydration impossible need medical attention.

- X-rays - plaque removal - Topical or oral antibiotics - surgery; grafting new tissue or deep cleaning - bone grafts or a special matrix - 30 - Signs and symptoms; X-rays

Periodontal Disease: - Dental ____ are also taken to check for bone loss. - If the disease isnt advanced, then _____ from the teeth and below the gums may be all that is required. - ___ or ____ may also be prescribed. - Advanced periodontitis requires ____ to help restore gums by either _______ to the affected region or ____ below the gum line to remove plague near the tooth root. - For bone degeneration, ____ or application of a special ____ to encourage bone growth can be used. - Almost half of adults over age ____ in the US have some stage of periodontal disease - Virulence factors and Transmission are the same as dental caries - ___ and ___ are main diagnostic criteria, along with ____ to assess bone loss.

- Anaerobic; Porphyromonas gingivalis and Tannerella forsythia - tender, swollen gums with a bright red or purplish coloration. - pull away from the teeth - bad breath and tooth loss - pull away; Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum - inflammation; bone damage and eventual tooth loss. - Regular brushing and flossing, along with regular dental visits and professional cleanings - groove; measured

Periodontal Disease: - caused by an _____ bacteria biofilm along the gum line, notably _____ and _____. - Characterized by ____, ____ gums with a ___ or ___ coloration. - The gums may also _____ from ____. - ___ and ____ are also frequent manifestations. - As the disease progresses, the swollen gums _____ from the teeth, forming gaps that can be colonized by anaerobic microbes such as _____, _____, and _____. - If not treated, the pronounced _____ that these bacteria trigger leads to ____ and eventual ____. - _____ and ____, along with _____ and _____, reduce plaque and therefore limit periodontal disease. - If the disease is suspected, the ____ between gums and teeth is _____ to assess the extent of the problem.

- white - common - colon - 4-12mm - 40 million - female worm - anal itching - fingers - scratch - contaminated surfaces or fingers - 3 weeks - disturbed sleep, test grinding, and anus itching

Pinworm (Enterobius vermicularis): - ____ roundworms - most _____ round worms that infect the intestinal tract - reside in ____ - __-__ long - ____ people in US are infected - Transmission: while the infected person is sleeping, the ____ migrates anus and lays eggs - Eggs cause intense ____ - Person scratches and eggs stick to ____. - Children are more likely to ___ - Pinworm eggs are ingested from _____ or ___- - Surface can harbor eggs for up to ____ - Symptoms: ____, ____, an ___-

- ingest the virus - dehydration - vaccinations combines with maintaining goo hygiene practices, and access to sanitized water - conclusive diagnostic test - RotaTeq and Rotarix - fever and vomiting followed by watery diarrhea; obvious

Rotavirus: - After touching a contaminated surface, such as a doorknob or countertop, people who do not wash their hands before eating may _______. - The main concern with rotavirus infection is the possibility of _____. - _____ combined with maintaining ______, such as washing hands before food preparation and eating, and access to ______ limit transmission. - The rapid identification of rotavirus antigens in stool samples is a ________. - Vaccination include _____ and ____. - Signs and Symptoms: Children tend to experience ____ and ____ followed by _____ that lasts 3-8 days. Adults tend to have less ____ signs and symptoms.

- 3 layers; tight junctions between intestinal cells - reverse transcription polymerase chain reaction (RT-PCR) - supportive therapy and intravenous fluid administration

Rotavirus: - Virulence factors: the viral capsid consists of _____, allowing the virus to survive and pass through the stomach unharmed. Once ingested, the virus invades and damages the _____ between _____ in a manner that causes water and electrolyte loss. - Diagnosis: Detect viral RNA in stool or vomit samples using ______, a specialized form of PCR. - _____ and ____ is used to treat severe dehydration.

- gastroenteritis - non enveloped, double-stranded, RNA genome, from the Reoviridae family - fecal-oral - inanimate objects or fomites - feces; fecal material

Rotavirus: - the leading cause of _____ in children under five years old - This ____, ____-stranded ____ genome from the _____ family, virus also infects adults, but symptoms are usually mild and may go unnoticed - Most cases are acquired through _____ transmission, in which contaminated food or water is ingested. - However, contaminated _____ or _____ can also transmit the virus- for example, a baby pacifier. - Infected patients may have trace amount of _____ on thier hands after going to the bathroom. If they don't wash their hands, they can transfer the _____ to the food they prepare or to common surfaces.

- S. enteritidis - typhoid toin - human to human - human sewage; food-handling practices - developing - fever, headache, arose-colored spotted rash constipation, and generalized abdominal pain; vomiting - Intestinal rupture, internal bleeding, and shock - Azithromycin - Thesalmonella typhi vaccine

Salmonella enterica Serovar Typhi: - Typhoid fever is caused by _____ serotype Typhi, which is much more dangerous than non typhoid salmonellosis - Increased virulence is primarily due to a toxin that its members make: the _____. - Typhoid fever is only spread from ____ to ____. - Transmission: _____ contaminates water or food or when someone is a carrier transmits the bacteria through unsanitary _____. - Common in _____ countries - Symptoms begin 1-2 weeks after exposure: ___, ____, a ____-colored _____, _____, and _____ that can last weeks; ____ is usually absent. - ____, ____, and ____ are potentially deadly complications - can be treated with antibiotics such as _____, but resistance multiple antibiotics is an increasing cancer. - ______ recommence for people traveling to endemic areas.

- undercooked meat and raw eggs, handling reptile pets (especially turtles), or live chickens - isolated - summer and fall - 6 hours to 3 days - Fecal-oral and direct contact - cooking meat and eggs, and using proper hand-washing and surface sanitation practices when handling meat and poultry or after handling pets - fever, vomiting, chills, headache, abdominal cramps, and diarrhea - 2-7 days and self-resolve - endocytosis; phagocytosis and multiplyinsiee macrophages - Culture bacterium; biochemical media and molecular methods - Supportive therapy; antibiotics; loperamide (Imodium) or diphenoxylate-atropine (Lomotil)

Salmonella enterica Serovars Enteritidis and Typhimurium: - Outbreaks are usually associated with consumption of ____ and ____, _____, or ____. - Most cases are ____, rather than part of mass outbreaks. - Cases occur throughout the year, but seasonality is observed, with peaks in ____ and ____ - Incubation period of ___ - ___ - _____ transmission and ____ with infected people - Prevent by thoroughly _____ and ____, and using proper ____ and ____ practices when handling meat and poultry or after handling pets. - Signs and Symptoms: ___ that tends to last a couple of days,____,____,____, ____,and ____ that may contain blood or mucus - Symptoms last __-__ days and usually ____ - Virulence Factors: Bacteria that survive acid barrier of the stomach induce intestinal epithelial cells to take them up by ____. Pathogens can escape ____ and multiply inside _____, killing them - Diagnosis: _____ bacterium from stool samples; Use various ______ and ______ that identify O and H antigens. - Treatment: _____ for mild cases; ______ given if it progresses to bacteremia and given to immune-compromised patients; - Antimotility agents like ____ or _____ may be used as long as dysentery, Shigella, and E. coli O157: H7 have been ruled out.

- diarrhea and dysentery - Gram-negative rod-shaped bacteria responsible for at least 1.2 million - S. enterica; O and H; S. enterica - Enteritidis and Typhimurium

Salmonella: - among the most causative agents of ____ and ____ - Gram-____ ____-shaped bacteria responsible for at least ____ food borne infections, called ____ per year in the US - Salmonella is divided into 2 species, of which only _____ includes pathogens that can infect humans. Using ____ and____ antigens for classification schemes, there are over 2,600 immunologically distinct varieties or serovars of _____. - The two most common diarrheagenic serovars in the US are ____ and ___

- Schistosoma haematobium, S. japonicum, and S. mansoni - importd - 200 million; 200,000 - fresh-water; miracicia; miracidia; second-stage; infectious larvae; penetrates; mature, mate, and migrate; blood; intestinal tract and/or bladder - migratory, acute, and chronic - a few days; rasher itchy skin - 2 months; wave; fever, chill, cough, and muscle aches - abdominal pain, enlarged liver, and swollen abdomen; vessels and tissues; deadly

Schistosomiasis: - caused by blood flukes: _______, ______, and ____- - rare in the US, all cases are ____- - infects ____ people worldwide and kills ____ per year - Life cycle: _____ source is contaminated with eggs, eggs mature into _____, ____ enters snails, Mature into a ______larvae, snails release ____into the water, _____ the skin of a human host, larvae _____, ____, and ____ to intestines or bladder via veins, fertilized eggs released in the _____, travel to the _____ and/or ____- and are released. - Symptoms: Course of infection has 3 stages ____, ____, and ____ - Migratory phase: occurs within ____of infection. ____ or _____ at the site of migration - Acute Phase: occurs within ____ of infection; coincides with first _____of egg release; ____, ____, ____, and _____. - Chronic phase: ____, ____, and ____; related to deposition of eggs in ___ and ____; cause fried and potentially _____ symptoms.

- Gram-negative bacteria; S. flexneri, S. sonnei, S. boydii, and S. dysenteriae - S. sonnei; S. flexneri - half a million - person to person and through human fecal contamination - 2 and 4 - watery or bloody diarrhea, abdominal pain, and fever - S. dysenteriae

Shigella: - Gram- ___ bacteria that include four pathogenic species: ____,____,____, and ____. - ____ accounts for about 75% of Shigella cases, while ____ predominates in developing countries. - Affects ____ people in US every year - spreads from ____ and through human _______ of food, water, and environmental surfaces that are touched. - Children between __&__ are most likely to become infected - Within a day or two of ingesting shigella, symptoms of frequent _____ or _____,_____, and ____ are typical. - ____ usually seen in Africa and Central America, it causes the most severe dysentery and carries a case fatality rate of 5-15%

- cytotoxic effects - hemolytic uremic syndrome - E.coli; E. coli - commandeering host cytoskeletal actin - macrophages; macrophage

Shigella: - Shiga toxins ______ are largely why S. dysenteriae has such a high mortality rate compared with other shigella species. - In some patients Shiga toxin can damage the kidneys and induce _______, symptoms include blood in the urine, bruising, and generalized swelling in the extremities. - Certain strains of _____ that have gained the capacity ti make the Shiga toxin are associated with HUS. Most HUS causes in the US are due to ____. - The ability of the bacterium to propel itself from host cell to the next by ____________ allows the pathogen to remain hidden from the immune system. - Even when host _____ manage to phagocytize Shigella, the bacterium releases substances that cause the ____ to undergo apoptosis allowing the pathogen to escape

1. endocytose 2. toxins 3. actin propulsion system 4. phagocytes - endocytosis induction system - enterotoxins - Shiga toxin

Shigella: Virulence Factors: 1. a system that induces host cells to _____ the bacteria 2. the manufacture of several ____ damage intestinal cells and induce fluid efflux 3. the capacity to pass between infected cells using an ______ 4. the ability to escape from _____ - the _______ involves the pathogen ingesting specialized proteins into the wound-be-host to induce it to internalize the bacterium by endocytosis. - Most shigella can make at least 1 of 2 _____ that damage intestinal cells and promote fluid efflux into the intestines, generating diarrhea - A third toxin, the _____, is only associate with S. dysenteriae; it targets ribosomes to block protein synthesis and kill host cells.

- antibiotics; proton pump inhibitor - Polar flagella; Enzymes; VacA - stool; blood samples - urea breath test - endoscopic evaluation - clarithromycin and amoxicillin along with a proton pump inhibitor

Stomach Ulcers: - Infections are curable with ____. In addition, a _______ is often prescribed to reduce stomach acid levels so that the stomach lining can more readily heal. - Virulence Factors: _____ help bacteria burrow into mucosal lining to escape stomach acid; ____ decrease the acidity around them.; Release toxin ____, which triggers host cell death. - H. pylori antigens can be detected in ____ or antibodies to the bacterium can be found in _____. - A ____ can indirectly identify the presence of the bacterium by detecting urea made by the organism. - Biopsy of the stomach lining during ______ can also confirm diagnosis. - Treatment is dual antibiotic therapy, often ____ and ____ along with a _____.

- 32 - T. saginata, T. solium, and T. asiatica - T. saginata - T. column and T. asiatica - definitive host - 50-100million - 1,000; immigrated 1. sewage 2. cattle or pigs 3. intestines 4. muscles 5. cysticerci 6. years - cysticerci

Taenia Species: - __ recognized Tania species - 3 cause human infections: ___, ____, and ____ - ____ infects mainly cattle - ____ and ___ infects pigs - These worms have a two-host life cycle whith humans being the _____ where the adult worms thrive and release eggs. - __-__ people infected worldwide - ____ cases per year in US, most occur in newly _____ people from Latin America 1. _____ contaminates areas where animals graze or housed. 2. ___or ___ ingest the worm eggs. 3. Eggs hatch in the ____ 4. Hatched larvae migrate to the animal's _____ 5. Larvae become _____ in the muscle 6. Can survive for ___ in the animal's tissues - Transmission: Ingestion of ____ in raw or undercooked meat

- asymptomatic; intestinal irritation and bowel obstruction - scolex and neck - intestinal wall - 5-12 weeks - eggs - Cysticercosis: 1. intestines 2. intestines. 3. tissues (brain, eye). 4. cysticerci. 5. tissue function. 6. deadly - Antihelminthic drugs and Anti-inflammatory agents - Surgery

Taenia species: - Symptoms: most infections are ___. Tapeworms can be very long which causes _____ and ____. - In the small intestine, the worm's ____ and ____ emerge from the cysticercus - Worm attaches to the ____ - Tapeworm reaches maturity after __-___ - Begins to release ____ -Complications: ____ occurs when humans ingest the T. solium eggs instead of cysticeri: 1. Eggs hatch in the ____; 2. Larvae burrow through the ____; 3. Migrate to _____; 4. Form ____; 5. Impair ____; 6. potentially _____ symptoms. - Treatment: ______ such as praziquantel and ______. - ____ may be needed to remove cysticerci in certain parts of the brain.

Falttened, segmented - scolex - proglottids - eggs and proglottids - Hymenolepis nana, Tania species, and Diphyllobothrium

Tapeworms: - ____, ____ bodies - have____ (head) at one end which has hook and/or sucker structures for attachment to intestinal lining. - Mature and release eggs as segments of the worm called _____ break off from the distal end in the definitive host - ____ and ____ released in feces - Most tapeworm infections in humans are linked to _____, _____, and _____.

Upper GI tract

The _____ includes the mouth, pharynx, esophagus, and stomach.

GI tract

The _____ is what comes in direct contact with our food. It extends from the mouth to the anus.

gastrointestinal tract and accessory organs

The digestive system consist of the _____ and ____

Accessory organs

The digestive system's _____, which include the salivary glands, liver, gallbladder, and pancreas, do not directly contact our food, but have essential roles in digestion.

- acute rather than chronic - Rotavirus and Norovirus

The immune system tends to mound a rapid and effective response to GI tract viral infections. Therefore, these illnesses are usually _____ rather than _____- meaning symptoms have sudden onset but quickly resolves rather than being sustained for long periods in the host. - _____ and _____ are the most common viruses that target the intestine to cause acute illness

- T. spiralis, roundworms - developed countries - dead-end hosts - embedded larvae; worms; blood; muscles - nausea, diarrhea, or vomiting; muscle pain, fever, headache, chills, or rash - cysts - few months - cardiovascular and nervous system; death - a cold or flu. Trichinella antibody test and Muscle biopsy - mebendazole or albendazole - raw or undercooked meat

Trichinellosis: - caused by Trichinella, mostly _____, ____- - Rare in ____- - Humans are ____ - Transmission: consuming _____ in undercooked meat. Larvae mutate into ____ in the intestine. Larvae migrate into ____. Embed in _____. - Symptoms: within a few days of consuming contaminated meat: _____, ____, or ___. Two weeks later:_____, ___, ____, ____, and ____ may occur - Severity depends on how many ____ were ingested - Eventually disappear within a ______. - Complications: high load of worms may lead to _____ and ____ effects, ____ is also possible but rare. - Diagnosis: mild cases re rarely diagnosed, usually mistaken for ___ or ____; _____ test and _____ can be used for diagnosis. - Treatment: drug treatment: ____or _____ - Prevention: avoid ____and _____

- mouth - parotid gland; enzymes; lipid and carbohydrate digestion - gastric juices, and protein digestion - microbial growth - alkaline mucus - chyme; small intestine

Upper GI tract: - Food enters at ___. - Salivary glands, of which the _____ is the largest, secret saliva that is rich in _____ that start ____ and _____ digestion. - The chewed food is swallowed and makes its way to the stomach, where it mixes with _____, and _______ begins. - The harshly acidic stomach environment limits _____. - The stomach itself is an expandable structure that is lined with _____, which protects the stomach tissue from the acidic gastric juices. - The food and gastric juices mix to form _____, which then enters the _____.

Hepatitis

_____ is a general term meaning inflammation of the liver. There are infectious and noninfectious sources.