Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
16 Cards in this Set
- Front
- Back
|
What is the influenza A virus?
|
orthomyxovirus - segmented genome
virus encoded in glycoproteins involved in adhesions to host mucous membranes vicus evades population immunity by constant antigenic change |
|
|
How is influenza A transmitted?
|
direct contact (aerosol)
recongnise repiratory tract receptors (N and H genes) natural reservoirs - domestic poultry, wild fowl |
|
|
How do you control the flu?
|
poultry are slaughtered
reduce exposure to wild birds and to viruses introduced from other poultry facilities Annual vaccine for humans (3 strains) |
|
|
What is avian influenza?
|
H5N1
first outbreak in 1997 - hong kong caused pneumonia with high fatality rate in humans 2002 china created their own in house killed H5N1 vaccine and was using it to vaccinate all domestic poultry 2004 began to spread, multiple countries affected - pneumonia in 60% of people people get it from chickens but no human human spread |
|
|
What was the Pandemic H1N1 of 2009?
|
swine influenza
rapid global spread -began in Mexico in April '09 -WHO declared pandemic in June '09 pathogenicity similar to seasonal influenza but much higher number of cases affected people with reduced lung capacity -pregnant -COPD -Asthma -Obese |
|
|
What is transmissible spongiform encephalopathy?
|
subviral particles ' infectious protein"
characterized by vacuolation of brain tissue can be transmitted between species genetic predisposition for developing overt disease well known in sheep -scrapie was the first described |
|
|
What is the pathogenesis of transmissible spongiform encephalopathy?
|
abnormal prion proteins
conformation is different PrPsc cannot be broken down in the body like PrPc and accumulates to toxic levels in the neurologic system |
|
|
How is transmissible spongiform encephalopathy transmitted?
|
ingestion of spongiform brain tissue usually transmit disease within members of the same species
experimental inoculation of spongiform brain into the brain of other mammal species |
|
|
What is chronic wasting disease?
|
found in deer, sometimes elk and rarely moose
increase testing has corresponded with increased acknowledge geographic range of CWD -people handling cervid tissue or eating meat could be exposed |
|
|
What are the species barriers for chronic wasting disease?
|
CWD is experimentally spread within herds of cervids although the exact route is poorly understood
attempts to infect carnivores via ingestion of CWD material has so far been unsuccessful -cattle were not infected by mule deer CWD when housed together for years -so far no human cases of vCJD associated with deer/elk cnsumption have been reported |
|
|
What is Dermatophytosis?
|
ringworm
-superficial fungal skin infectious -infectious are generally self limiting -spreads by contact and by spores on fomites -immunity requires a strong cell mediated immune response |
|
|
What is microsporum canis?
|
most common dermatophytosis in the developing world
cats are usually asymptomatic carriers humans immune response against M canis is usually long lasting |
|
|
What are causes of fungal pulmonary infections?
|
infections from spores in the environment that become aerosolized and are inhaled
birds and bats can be reservoirs fecal exceretion = soil contaimination infected humans, dogs and cars are generally not infectious, body temperature is to high for sporulation of these fungi histoplasma and cyptococcus are opportunistic |
|
|
How do you identify Histoplasma capsulatum?
|
ID based on culture, microscopic appearance of spore-forming colonies or upon detection of DNA using PCR
|
|
|
What do you see with acute fungal pulmonary infections?
|
extensive inflammation often pneumonia
symptoms: high fever, night sweats, enlarged pulmonary lymph nodes, see radiographic masses |
|
|
What happens if the immune system fails to control acute pulmonary infections?
|
becomes chronic
spreads to other tissues more likely with compromised immunity or with more pathogenic fungal species |
