Microbiology CHAPTER 39

How do we treat, prevent, and control plague ?

1. Antibiotic therapy 2. Ectoparasite and rodent control, isolation of human patients, prophylaxis of exposed persons, immunization of persons at high risk

What are virulence factors associated with Streptococcal Diseases?

1. Extra cellular enzymes that break down host molecules 2. Streptokinase (SK), which dissolves blood clots extracellularly 3. Streptolysin O and S which kill host leukocytes 4. Capsules and M proteins for attachment and retard phagocytosis

How do we treat, prevent, and control MAC Infection?

1. Isolating sputum, blood, or bone marrow 2. Acid-fast stain and immunodiagnostic tests 3.multiple drug therapy

What is the course of disease of TB?

1. Often the lung macrophages infected with Mtb try to kill the bacteria, but die in the attempt. 2. TUBERCLES FORM: these are composed of bacteria, macrophages, T cells, and human proteins

Where does pneumonic plague come from ?

1. Primary exposure to infectious respiratory droplets of infected people or cats 2. Secondary to hematogenous spread in a patient with bubonic plague.

What is the function of the 3 exotoxins of Anthrax that help kill phagocytic macrophages ?

1. Protective Antigen: forms a donut home in the cel for entry of other toxins 2. Edema factor: fluid release and edema 3. Lethal factor: inhibits cytokine production

What are the clinical manifestations (symptoms) of Mycobacterium Infections (MAC INFECTIONS)

1. Pulmonary infections (tuberculosis), seen in elderly patients with preexisting pulmonary disease. 2. Gastrointestinal infections that come with fever, malaise, weight loss, and diarrhea. Common in AIDS patients.

What are main example of direct contact Diseases ?

1. Sexually transmitted diseases 2. Peptic ulcer Diseases (gastritis) 3. Staphylococcal Diseases

Mycobacterium Tuberculosis has factors that contribute to its virulence... what are they?

1. TOXIC CELL ENVELOPE: includes mycolic acid. These kill eukaryotic cells and protect Mtb from lysozyme and osmotic lysis. 2. SURVIVE PHAGOCYTOSIS: Kills macrophages!!!! Is resistant to oxidative killing, and inhibits diffusion of lysosomal enzymes

How do we treat, prevent, and control Legionnaires' Disease?

1. by symptomatic, supportive, and antibiotic therapy 2. Isolation of bacteria and immunodiagnostics 3. Eliminate nosocomial spread (spread in hospital) 4. Identifying and eliminating the environmental source

How is TB transmitted ?

1.Person to person spread by droplet of nuclei in the respiratory tract. 2. Infected animals and their products 3. Re activation of old or dormant infections.

How do we treat, prevent, and control H. Pylori Disease ?

A combination of drugs to decrease stomach acid and antibiotics to kill the bacteria.

What is Streptococcal Pharyngitis?

A common infection called strep theist that spreads by droplets of saliva/ nasal secretion, infection the throat (pharyngitis) or tonsils (tonsillitis)

Peptic Ulcer Disease and Gastritis

A disease caused by gram negative helicobacter pylori, produces urease which increases pH and releases toxins that damage epithelial mucosal cells.

Legionella Pneumophila

A gram negative rod, aerobic, and nutritionally fastidious GAMMAPROTEOBACTERIA which spreads by AIRBORNE transmission from environmental reservoir to human host. Reservoirs include: soil, aquatic ecosystems, air conditioning systems, and shower stalls

Multi-Drug-Resistant strains (MDR-TB) or Extensively Drug Resistant strains (XDR-TB)

A lot of TB is resistant to antimicrobial therapy due to naturally occurring chromosomal mutations and natural selection of resistant Mtb due to lack of adherence to treatment protocol.

Tuberculosis (TB)

A slowly developing disease caused by Mycobacterium tuberculosis (Mtb) which is present in 1/3 people worldwide.

Acquired Enamel pellicle

A type of dental plaque that is formed when enamel absorbs acidic glycoproteins from saliva and are colonized by various bacterial species to form plaque (strep)

Periodontosis

A type of periodontal disease & Bone destruction caused by colonization of periodontal pockets

Periodontitis

A type of periodontal disease & Gum disorder in which starts with inflammatory response to plaque bacteria and tissue destruction, which leads to swelling of tissue/formation of periodontal pockets

Gingivitis

A type of periodontal disease & Inflammation of gingiva caused by colonization of periodontal pockets

Legionnaires' Disease

A type of pneumonia(lung infection) caused by Legionella Pneumophila where bacteria reproduces in ALVEOLAR MACROPHAGES and causes localized tissue destruction.

What type of stain is used on Mycobacterium and why?

Acid fast staining, because gram staining will not work due to presence of mycolic acid.

How do we diagnose someone with TB?

Acid-fast bacteria, chest x-ray, mantoux, or tuberculin skin test, DNA based tests

Pulmonary Anthrax

Also called Woolsorters Disease, and is inhalation of endospores, resembles influenza. If the bacteria enters blood stream, its typically fatal

How do we treat, prevent, and control Anthrax ?

Antibiotic therapy and symptomatic and supportive therapy, immunization of animals and persons at high risk

Who do we treat, prevent, and control STD's ?

Antibiotic therapy most effective in early stages, public education, prompt treatment of new cases, follow-up on sources and contacts, sexual hygiene, and use of condoms

What is the virulence of Anthrax ?

B. Anthracis evades immune system by capsules which inhibit phagocytosis and synthesize complex exotoxins

Where does the plague attack the body ?

Bacteria of the plague multiply in the blood and lymph nodes (cause buboes). They survive and proliferate in phagocytosis cells

How can we diagnose bacterial meningitis ?

By a gram stain of Cerebrospinal Fluid(CFS). The culture may or may not grow bacteria

How do we prevent and control TB?

By rapid, specific therapy to interrupt spread, retreatment of patients with MDR-TB immunization, improved sanitation and housing, and reduction in homelessness and drug abuse.

How is Meningitis transmitted?

By respiratory droplets

What happens when demineralization is created than remineralization?

Caries are formed

Botulism

Caused by the bacteria clostridium botulinum typically coming from insufficiently heated home canned food.

Escherichia Coli Gastroenteritis

Causes travelers diarrhea from certain virus, bacteria, or Protozoa nor typical of the travelers environment

Mycobacterium Infections

Commonly known as the M. Avium Complex, these infections are typically caused by actinobacteria, and cause a number of human infections that are difficult to treat.

What are the symptoms of Infant Botulism ?

Constipation, listlessness, general weakness, poor appetite, may cause death due to RESPIRATORY failure

How is H. Pylori Disease diagnosed ?

Culturing gastric biopsy specimens, examination of stained biopsies, serological testing, urea breath test, tests for ammonia in urine, detection of urease activity in biopsies.

How do we diagnose, treat, and control Streptococcal Pharyngitis?

Diagnose using rapid kits. 1. Antibiotics 2. Prevent contact with contaminated items from infected individual.

Anthrax

Disease caused by bacillus anthracis that is transmitted by direct contact with infected animals or their products(portal of entry determine form of the disease) and is a potential bioterrorism agent

Periodontal Disease

Diverse group of inflammatory diseases that affect the periodontium (supporting structure of tooth), initiated by formation of subgingival plaque

Who is most likely to have TB?

Elderly, homeless, alcoholics, prisoners, immigrants

What are the clinical manifestations(symptoms) of Legionnaires' Disease?

Fever, cough, headache, neuralgia, and bronchopneumonia. This disease is especially severe in those with comprised immune systems

What are the symptoms of TB?

Fever, fatigue, weight loss, cough (may be associated with bloody sputum)

What causes Streptococcal Diseases?

G+, beta hemolytic bacteria called Streptococcus Pyogenes

How is botulism spread?

If insufficient cooking of food, endispores are not killed and they then produce a neurotoxin causes lung muscle contrast problems

Cutaneous Anthrax

Infects through a cut or abrasion of skin, takes 1-15 days to show symptoms of skin papule that ulcerates, headache, fever, nausea. Cured through antibiotic therapy

Gastroenteritis

Inflammation of stomach and Intestinal lining

Meningitis

Inflammation of the BRAIN OR SPINAL CORD MENINGES caused by bacterium.

Gastrointestinal Anthrax

Ingestion of endospores

Good intoxication

Ingestion of toxin; enterotoxins disrupt functioning of intestinal mucosa causing nausea, vomiting, and diarrhea

What are the clinical manifestations (symptoms) of Meningitis?

Initially causes respiratory illness/sore throat, which is then interrupted by vomiting, headache, lethargy, confusion, and stiffness in neck and back. May be fatal.

Why is presence of dental plaque bad ?

It creates environment for pathogens that produce acids and other virulence factors

How do we diagnose plague ?

Made in reference labs which use direct microscopic examination, culture and serological tests, and PCR

What is something commonly seen in those who have and die from TB?

Many are positive for HIV. Many AIDS patients die from TB (over 50%)

Opportunistic Diseases

Microbes that may become pathogens, but are otherwise members of the normal microbiota

What causes epidemic meningitis?

N. Meningitidis

How do we treat, prevent, and control dental decay?

No drug treatment available, but good dental hygiene and minimal ingestion of sucrose can help prevent.

Clostridium Botulinum

Obligate aneroid, endospore forming, gram positive bacteria on the select agent list

Infant botulism

Occurs when endospores are ingested (HONEY, HOUSE DUST) and they germinate to produce an exotoxins.

How do we treat, prevent, and control Gingivitis?

Oral surgery and antibiotic therapy in some cases, plaque removal and good dental hygiene.

How do we diagnose travelers disease ?

Past travel history/symptoms, isolation and identity of causative agents using DNA probes, test for virulence factors, and PCR

How is H. Pylori Disease transmitted ? How many people are infected world wide ?

Person to person, there is no common source known. 50%

What is the main species involved in Periodontal Disease ?

Porphyromonas Gingivalis

How do we diagnose Anthrax ?

Presumptive ID in sentinel land of Laboratory Response Network (LRN), use of gram-stained smear of skin lesion, cerebrospinal fluid, or blood, use of PCR and serology

Demineralization/remineralization cycle of dental decay

Production of acids leads to release of calcium and phosphate ions from enamel followed by remineralization

What are the physical manifestations of Streptococcal Pharyngitis?

Redness, edema, lymph nods enlargement in thrust

Plague

Select agent list

What causes bacterial Meningitis?

Streptococcus pneumonia, Neisseria meningitidis, and Haemophilus influenza, or an Endogenous infection (a normal biota typically found in the body but is dormant).

What are the clinical manifestions (symptoms) of Plague ?

Subcutaneous hemorrhages, fever. Buboes.

How do we treat, prevent, and control Infant Botulism

Symptomatic and supportive therapy and administration of antitoxin, safe food processing practices and not feeding honey to babies under one year old

How do we treat, control, and prevent Travelers disease ?

Symptomatic/supportive therapy and antibiotic therapy, avoiding contaminated food or water

Coaggregation

The attachment of different species of bacteria to each other, based on cell to cell recognition (actinomycetes and biofilms)

Arthropod Borne Diseases

These diseases are rare, and includes Lyme disease (ticks), Plague (rodents), and Rocky Mountain Spotted Fever (ticks)

Where are these bacteria found ?

These epsilon proteobacteria colonize gastric mucus-secreting cells, beneath gastric mucosa.

Why are Mycobacterium infections hard to treat?

They're hard to treat due to mycolic acid in the cell walls (waxy protective material) which creates resistance to penetration of antibiotics.

How do Mycobacterium Infections spread? Where are they typically found in the environment?

They're ineffective person to person transmission, and usually use respiratory or gastrointestinal tract as a mood of entry. They're inhabitants of soil and water

Dental disease

This disease is caused by odontopathogens, and cause formation of dental plaque

Plague

This is a gram negative arthropod-borne disease. Its transmission initially starts from the bite of an infected flea, and spreads by direct contact with infected rodent or airborne droplets.

How are food and water borne diseases prevented or controlled ?

Through sanitation measures.

Helicobacter pylori produce urease increasing pH (urease to ammonia)... why?

To protect themselves from gastric acid.

What is the virulence factor of the plague ?

Type 3 secretion systems deliver yersinal outer membrane proteins (YOPS): into cells and shut down defense mechanisms. Spore form on membrane, and inhibit phagocytosis.

Zoonotic Disease

Type of disease transmitted from animals to humans

Food poisoning

When food is a source of pathogen

Food-borne Infection

When the pathogen must colonize the host, but comes from good.

STD's

Worldwide health problem transmitted through sexual and on sexual means. Typical in those ages 15-30, includes gonorrhea and syphilis.