Emerging vector borne diseases Flashcards
(39 cards)
Give 3 EGs of Tick-borne VBDs
1) Lyme
2) Tick-borne rickettsias
3) African swine fever
Give 2 EGs of mosquito-borne VBDs
1) Heartworm
2) west nile
EG of sandfly borne VBD
Canine leishmania
3 EGs of midge-borne VBDs
1) Bluetounge
2) Africa horse sickness
3) Schmallenberg
Define an emerging disease
- a disease that has newly appeared in a population, or that existed previously but is rapidly increasing in incidence or geographic range
Define a vector-borne disease 3
1) A disease caused by a pathogen spread by an arthropod host
2) Not a disease with an intermediate host (eg snail)
3) Not a disease caused by the arthopod itself
Where, when and how many horses did the two african horse sickness epidemics cause?
1) western cape, 1854-55, killed 40% of entire horse population
2) middle east,1959-60,killed 300,000 equids
when, where and how many pigs did the two outbreaks of african swine fever cause?
1) cuba, 1971, 400 000 pigs diesd or slaughtered
2) cameroon, 1982, 80% of all swine destroyed
When, where and how many sheep di the two epidemics of bluetongue cause?
1) southern europe 1998-05, 1 mil
2) Northern europe, 2007, 200,000 cases on 60,000 farms
Rift valley fever -where, when how much $ lost?
Somalia, 1998-2002, export loss about $435 mil
screworm- libya, 1989-1991, eradication costs
libya, 1989-1991 about 66 mil
hard tick families
Ixodes, Rhipicephalus
Soft ticks
Argasidae
Describe Lyme disease
- borreliosis
- spirochaete, borrilia burgdorferi, spread by ixodes ricinus “sheep/deer tick”
- disease of people, large animals, dogs
- important emerging human disease causes: rash, flu,fatigue,joint pain,neuroborreliosis
- not of major importance in dogs but can cause fever, lameness, joint pain, swollen lymph nodes, lethagy and inappetance
- in UK >1000 confirmed human cases pey year
- prevalence of borrelia-infected ticks on UK dogs:481 per 100,000 dogs (0.5%)
Whatare the drivers of lyme disease emergence
-Spread of ticks to higher altitudes and latitudes (likely related to climate and landscape change (more deer?))
What is the most common vector for babesiosis, ehrlichiosis and anaplasmosis?
Ixodes ricinus (sheep/deer tick)
what does Dermacentor reticulatus spread
Ornate cow tick- now present in southern england
what does Rhipicephalus snaguineus (brown dog tick) spread?
-babesia, ehrlichiosis anaplasmosis and rickettsia rickettsii
incersions into the UK infests some houses
what is mediterranean spotted fever, spread by?
Rickettsia conorii spread by Rh. sanguineus, little clinical importance but high prevalence
What is a driver of the emergence of hard tick borne diseases?
1) spread of ticks- probably related to climate
2) increased movement of animals( eg dogs)
3) changes in international regulations - dont have to treat dogs to cross border
whats special about african swine fever
only dsDNA virus known in the group arboviridiae
Describe african swine fever
- Causes fatal haemorrhagic disease of pigs; infects boar and warthogs
- spreads by aerosol, the bites of ornithodorus soft ticks or in feed
- highly stable virus: survives 15 weeks in chilled meats; 6-9 months in cured meats; 15 years in frozen meats
- no vaccine. outbreaks dealt with by culling and stamping out.
describe african swine fever emergence
- Endemic in africa
- endemic in boar in sardinia with spill-over into domestic kids
- spread to eastern europe
- western europe at high risk
Name a zoonotic disease transmitted by mosies and discribe
Heartworm, severe and potentially fatal for dogs and cats,Dirofilaria immitis and D. repens transmitted by mosquitoes, originated in USA but now global, including europe, usually sub-clinical or chronic infection for years., can infect humans
