THE MOLECULAR EPIDEMIOLOGY OF BLUETONGUE VIRUS INFECTION IN EUROPE: IMPACT OF VACCINATION

摘要

Bluetongue virus (BTV) is endemic in warmer regions around the world, between ~45-53°N and 35°S, including North and South America, Africa, the Indian subcontinent, Australasia, and Asia (Mertens et al 2007b). BTV is transmitted primarily by adult female hematophagous midges (genus Culicoides - Mellor and Boorman, 1995) and can infect most ruminants or camelids (Chandel et al., 2003; Ruiz-Fons et al., 2008). However, the virus can also be transmitted vertically in cattle and sheep (Menzies et al.,2008), and can infect certain large carnivores via an oral route or injection (Jauniaux et al., 2008). There is also some evidence that BTV can be transmitted vertically in the midge (White et al 2005). The severity of the disease is dependent on host species, breed/strain, and on their serological status for BTV. However, it is also dependent on the virus itself and attenuated strains have long been used as 'live vaccines' (Veronesi et al., 2005).