Public health ento exam 4 (PPT 4-6)
What is the mortality rate of scrub typhus if treated?
< 2%
What is scrub typhus?
A bacterial infection transmitted by mites.
What is the Black Death?
A pandemic that killed 75-200 million people across Eurasia and Northern Africa from 1347-1352.
What is guinea worm?
A parasitic worm that causes painful blisters.
What is scabies?
A skin infestation caused by a mite.
What is blue tongue virus?
A virus that affects sheep, goats, cattle, deer.
What is Oropouche virus?
A virus transmitted by Culicoides midges and mosquitoes.
Where are the 2 species of filarial worms found?
Africa.
What is flea allergy dermatitis?
An allergic reaction to flea saliva
What are the challenges in eradicating Guinea worm?
Animal infections, inability to surveille due to country insecurity
What is the intermediate host for Guinea worm?
Arthropod (crustacean copepod)
What are nuisances?
Biting midges, mites, bedbugs, no-see-ums, etc.
What is the difference between bubonic and pneumonic plague?
Bubonic affects lymph nodes, pneumonic affects lungs.
What are the three types of plague?
Bubonic, septicemic, and pneumonic
What is the symptom of Guinea worm infection?
Burning blister, painful, disabling, secondary infections
What are the diseases caused by Bartonella henselae?
Cat scratch disease and bartonelloses
Where is the 1 species of filarial worm found?
Central and South America.
What is the scientific name for biting midges?
Ceratopogonidae.
How can Guinea worm be prevented?
Clean water supply, prevent contact with water supply, Guinea worm control program
What is the mode of transmission of scabies?
Close contact
What is the mortality rate of pneumonic plague if untreated?
Close to 100%.
What is the most effective way to prevent plague?
Control of rodent and flea populations.
What are the symptoms of pneumonic plague?
Coughing, fever, headache, weakness, rapid onset of pneumonia, shortness of breath, chest pain, bloody sputum.
Which countries were affected by the Black Death?
Cyprus, France, Germany, Norway, and eastern European countries.
What is necrosis of extremities?
Death of tissue in the extremities.
What is the scientific name of the nematode that causes Guinea worm disease?
Dracunculus medinensis
What is murine typhus?
Endemic typhus caused by Rickettsia typhi
What are the symptoms of bubonic plague?
Enlarged or necrotic lymph nodes, fever, chills, diarrhea, extreme exhaustion, headache
What are the symptoms of scabies infestation?
Extreme pruritis, tunnels in skin, scabies rash
What are the symptoms of septicemic plague?
Fever, chills, abdominal pain, sneezing/vomiting blood, red spots on skin
What are the symptoms of Oropouche virus?
Fever, chills, headache, anorexia, myalgia, joint pain, vomiting, meningitis.
What are the symptoms of septicemic plague?
Fever, chills, weakness, abdominal pain, vomiting, diarrhea, bleeding from mouth, nose, rectum, or under skin.
What are the symptoms of bubonic plague?
Fever, chills, weakness, swollen and painful lymph nodes.
What are the symptoms of scrub typhus?
Fever, headache, muscle pain, cough, gastrointestinal symptoms, and less commonly, hemorrhaging and intravascular coagulation
What is the transmission route for Yersinia pestis?
Flea bite or contact with infected animals
What is flea dirt?
Flea excrement
What is the transmission route for murine typhus?
Flea feces or crushing
What is the vector for plague transmission?
Fleas.
What is the common name of Dracunculus medinensis?
Guinea worm
What are the symptoms of murine typhus?
Headache, fever, chills, muscle pain, nausea, vomiting, cough
What is Norwegian scabies?
Heavy infestation of scabies causing scaly, thickened skin and less itchiness due to immune system response
What is the flea life cycle?
Holometabolous
What is contact tracing?
Identifying and monitoring individuals who may have come into contact with an infected person.
What is the mortality rate of murine typhus?
~2%
How many cases of the plague occur per year worldwide?
1,000-3,000 cases per year.
How many species of Culicoides midges are there?
1,450.
How many human cases of the plague occur per year in the US?
10-15 cases per year, often in rural communities.
How many people did the Black Death kill in China and India?
12 million people.
What is the mortality rate of bubonic plague without treatment?
15%
When was the last urban outbreak of the plague in the US?
1924 in Los Angeles, CA.
When was the Guinea worm control program initiated?
1986 by Carter Center
What is the incubation period for plague?
2-6 days.
How many cases of Oropouche virus were there in South America?
263,000, with 130,000 occurring in a two-year span from 1978-1980.
What is the maximum length that the female Guinea worm can reach?
3 ft
How many human cases of scabies are there worldwide each year?
300 million
What is the history of plague?
3000 BC: Yersinia pestis in Swedish tomb, 541-750: First plague pandemic spreads from Egypt to the Mediterranean and NW Europe, 1346-1840: Second plague pandemic spreads from Central Asia to the Mediterranean, 1855-1960: Third plague pandemic spreads from China across the world.
What is the mortality rate of septicemic plague with treatment?
4-15%
What is the mortality rate of scrub typhus if left untreated?
40%
What is the mortality rate of bubonic plague with treatment?
50-90%
What is tungiasis?
Infestation by Tunga penetrans flea
What is the treatment for scabies?
Insecticide creams, avoid close contact, oral ivermectin
What is the treatment for plague?
Isolate patient, antibiotics, supportive treatment to prevent organ failure, contact tracing, control flea population, control rat population.
How did the Black Death spread?
It started in Mongolia and spread through trade routes.
What are the reproductive issues caused by mites?
Limited vaccine, no treatment
How many cases of Oropouche virus were estimated in Brazil alone?
More than 500,000.
What is the treatment for septicemic plague?
Must begin within 24 hours of onset
Is there any treatment or vaccine for Guinea worm?
No
Is there a treatment for blue tongue virus?
No, but there is a limited vaccine.
Is Guinea worm a filarial worm?
No, it is not a filarial worm
Is blue tongue virus of public health importance for humans?
No.
What are fleas?
Obligate ectoparasites (adults)
What is Siphonaptera?
Order of fleas
What is sensilium?
Organ for sensing
What is the scientific name of the bacterium that causes scrub typhus?
Orientia tsutsugamushi
How many species of biting midges are there?
Over 5,500.
What are the effects of biting midges?
Painful bites, allergies, sweet itch in horses, economic loss.
What are filarial worms?
Parasitic worms transmitted by Culicoides midges.
What is de-urbanization?
People fleeing cities and bringing the plague with them.
How is pneumonic plague transmitted?
Person to person via infected sputum or other body fluids.
What are the symptoms of tungiasis?
Pruritis, secondary infections, lymphedema, gangrene
What are some important synanthropic fleas?
Pulex irritans, Ctenocephalides felis, Ctenocephalides canis, Xenopsylla cheopsis, Nosopsyllus faciatus
What is the reservoir for plague?
Rodents.
What is the scientific name of the mite that causes scabies?
Sarcoptes scabiei
What is the vectorial capacity of Yersinia pestis?
Starving flea increases feeding, blocks alimentary canal
What are the host-seeking behaviors of fleas?
Temperature, air movement, vibrations, light, host volatiles
What is the Black Death?
The Black Death of 1346-1353 resulted in an estimated 200 million deaths.
What was the impact of the Black Death on labor?
There was a massive loss of life, leading to a shortage of labor and the end of serfdom and rise of the European middle class.
What happened after the Black Death?
There were resurgences of smaller, localized epidemics in various cities, such as Paris, Moscow, Venice, Amsterdam, and London.
What are no-see-ums?
Tiny biting midges.
What is the scientific name of the chigger mite?
Trombicula sp.
What is the scientific name of the mite that causes scrub typhus?
Trombicula sp.
What are the symptoms of blue tongue virus?
Ulcers, sores, painful hooves, lameness, blueish tongue, reproductive issues, some mortality.
What are the preventive measures for scrub typhus?
Use of DEET, wearing loose clothing, bathing in soapy water, and waiting out the itching for 10-14 days
What is the sylvatic cycle of plague transmission?
Variety of flea vectors, hunters and trappers can still be affected by this cycle.
Who developed the vaccine for plague?
Waldemar Haffkine in 1897.
What are the reservoirs for the plague?
Wild rodents, but rats, dogs, and cats can also become infected.
What is the vector for Yersinia pestis?
Xenopsylla cheopsis flea
What is the vector for murine typhus?
Xenopsylla cheopsis flea
What is the urban cycle of plague transmission?
Xenopsylla cheopsis, possibly Pulex irritans (human flea) and Pediculus humanus (body louse).
What is the causative agent of plague?
Yersinia pestis.