Vaccination of Non-Domestic Animals against Emerging Virus Infections

Abstract

Since the 1980's, emerging and re-emerging infectious diseases have made an enormous impact on public and animal health, food supply, economies, and the environment. An estimated 75% of emerging infectious diseases in humans are zoonotic (pathogens of non-human vertebrate animals that may be transmitted to humans under natural conditions), mainly of viral origin and often vector-borne. Since 1980, more than 35 new infectious agents have emerged in humans , including Severe Acquired Respiratory Syndrome (SARS coronavirus) , West Nile Virus (WNV) 5, Ebola virus 6 and Avian Influenza A Virus (AIV). Although the recognition of emerging or reemerging infectious diseases can in part be attributed to increased interest or attention and to improved diagnostic methods, the foremost cause should be sought in human behaviour: (1) demographic changes: exponential growth of the human population, world-wide urbanisation, encroachment on wildlife habitat; (2) generalised social changes: globalisation of trade, increased and accelerated legal and illegal transport of animals, wildlife trade (live animal and bushmeat markets); (3) ecosystem disturbance: deforestation, eutrophication of waterways; and (4) climatic changes: global warming. Livestock has been severely affected by direct mortality and depopulation policies, for example: to date, highly pathogenic avian influenza (H5N1) has resulted in culling of at least 220 million birds in 41 countries. The impact of emerging infections is of special concern for endangered wild animal populations, which can be pushed to the brink of extinction by such events.