A Change in the Epidemiology of Bovine Cysticercosis in Israel Between 1973 and 2008 Due to Import of Live Cattle

Abstract

Bovine cysticercosis (BC) is an important disease because of its zoonotic nature. There is a significant variation in the prevalence of BC in different countries, ranging from <0.01% to more than 20%. In this study, we followed the changes of BC prevalence in Israel during the last four decades and examined its association with import of live cattle. During 1973-2007, 629,549 cattle were subjected to post-mortem inspection conducted in 'Marbek' slaughterhouse located in the south of Israel. A specific comparison was made between the prevalence of BC in local and imported cattle during 2003-2007. Of 629,549 cattle, 2568 were infected with Cysticercus bovis (0.4%). From 1980, there was a gradual decrease in the prevalence of BC (R(2) = 0.53) with exceptional peaks. Moreover, from 1973 to 1998, only 4% of the documented cases appeared in outbreaks as opposed to 38% after 1998 when mass importation of live cattle to Israel was initiated. All of these late outbreak cases appeared in imported cattle of which 95% originated from Australia. During the years 2002-2007, importation from Australia was found as a significant risk factor for infection with BC, with prevalence in these cattle reaching 1.8% in 2006. The time from importation to BC detection suggests that infection occurred either in Australia or during the transport into Israel. We conclude that despite a reduction in the prevalence of BC as a result of a possible improvement in sanitary conditions at the farms, meticulous meat inspection is still essential in Israel and possibly in other developed countries exporting and importing live cattle.