Page 485 - The Veterinary Laboratory and Field Manual 3rd Edition

422 Matilde Tomaselli and Patricia Curry

Table 11.1 continued

Family/class (species) disease name (aetiology) Comments
Equidae Susceptible to vector-borne Affects most wild equids; vector control
(horses, donkeys, and diseases, such as equine is important in the control of vector borne
zebras) encephalitis encephalitis; mosquitoes and birds often play
an important role in the disease ecology.
African horse sickness Spread by midges.
(Orbivirus)
Glanders Zoonotic.
(Burkholderia mallei)
Aves Avian influenza Low pathogenic (LP) strains are distributed
(wild and domestic (Orthomyxoviruses) worldwide with a number of migratory wild
birds) birds acting as reservoirs; highly pathogenic
(HP) strains derive from mutations of LPs.
Severe systemic disease with high morbidity
and mortality for HPs. Transmission through
direct contact and airborne. Some strains are
zoonotic and cause mortality in humans.
Avian pox Often mild and self-limiting disease but
(Poxvirus) some outbreaks have high mortality; most
bird species are susceptible; worldwide
distribution but higher infection rates in
temperate and warm climates; transmitted
through direct contact, environmental
contamination and vectors (mosquitoes).
Newcastle disease Highly contagious and severe disease with
(Paramyxovirus) worldwide distribution; some wild birds can
carry the virus without becoming ill (e.g.
pigeon-like birds shed intermittently the virus
for 1 year); transmission through direct contact
with infected or carrier birds. Zoonotic.
Avian cholera Transmitted through direct contact or
(Pasteurella multocida) environment contamination; wild birds but
also mammals can carry the infection; sudden
mortality is observed in the acute form of
avian cholera, while localized infections are
evident in the chronic form.

animals (for example, rabies). Habitat modifi- 11.2 Practical considerations for
cation and human encroachment into wildlife designing a disease survey in
habitat can also lead to complex interactions wildlife
that increase the risk of exposure to zoonotic
pathogens for both humans (for example, Ebola Although the approach to wildlife disease sur-
virus) and naïve wildlife (for example, human- veillance is similar to that taken with livestock, it
associated respiratory infections in populations is usually more difficult to obtain epidemiologi-
of endangered great apes). cal information from free-ranging species. This

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