![]() There is some evidence to suggest that BEF is immune mediated in nature and that the clinical characteristics of the disease are the expression of mediators of inflammation common to a number of acute febrile diseases with a secondary hypocalcaemia. Outbreaks of BEF occur when vector-probably mosquito-populations increase, resulting in high rates of virus transmission to susceptible cattle. Īccording to Sellers, Israel and the rest of the Mediterranean area are in zone “C”, in which pathogens are introduced by infected vectors carried on warm winds. BEF is spread by movement of the host or by vectors, but long-distance carriage of infected insects by the wind has most likely been responsible for the spread of BEF in various countries. The virus agent has been isolated from various species of midges and mosquitoes, which are probably the main vectors. BEF is not transmitted by close contact, bodily secretions, or aerosol droplets, and carriers are not known to occur. The BEF virus life-cycle is maintained through a vector-host system. are the vectors of the BEF virus in Israel.īovine ephemeral fever (BEF), caused by the bovine ephemeral fever virus (family Rhabdoviridae, genus Ephemerovirus) is a noncontagious inflammatory disease, of short duration, that affects cattle. It is hypothesized that mosquitoes and not Culicoides spp. All affected cattle were over the age of 3 months. In heifers from 1 year to calving, the morbidity rates were 13.8%, 14.9%, and 28%, respectively, in first calvers 30.8%, 31.6%, and 28.3%, respectively, and in cows 34.3%, 35.7%, and 27.2%, respectively. Comparison among the various age groups showed that the lowest morbidity rates were observed in the youngest age group, that is, heifers up to 1 year, with 3.2%, 3.6%, and 4.2% in 1990, 1999, and 2004, respectively. The average sero-positivity to BEF in 1999 was 39.5%, which matched the morbidity rate. The highest herd incidence, morbidity, and case fatality rates were noted in dairy cattle herds in the Jordan Valley, with morbidity of 20%, 38.6%, and 22.2%, and case fatality rate among affected animals of 2%, 8.6%, and 5.4% in 1990, 1999, and 2004, respectively. The disease broke out under optimal ecological conditions, among a vulnerable cattle population and spread rapidly it showed essentially a spring-summer herd incidence and terminated soon after the night average ambient temperature fell below 16☌ in late autumn. In the 2004 outbreak, the primary focus of the disease was the southern Mediterranean coastal plain and the disease agent was apparently brought by infected mosquitoes carried from their breeding site in the Nile Delta by the south-western winds. The main patterns of BEF spread were similar in the 1990 and in 1999 epidemics, and the BEF virus was probably carried in vectors transported by air streams across the Rift Valley and the Red Sea. SOFIA KOSTOPOULOU, ANGELOS G.Outbreaks of bovine ephemeral fever (BEF) occurred in Israel in 1990, 1999, and 2004.MIRKO BELAK, DAMIR SLOVENEC, TEA KOLAR-JURKOVŠEK, VESNICA GARAŠIĆ, ZOLTAN PÉCSKAY, DARKO TIBLJAŠ, IVAN MIŠURLow-grade metamorphic rocks of the Tethys subduction–collision zone in the Medvednica Mt.MARTIN ĐAKOVIĆ, DRAGOMAN RABRENOVIĆ, DIVNA JOVANOVIĆ, MILAN SUDAR, MILOŠ RADONJIĆBiostratigraphy on ammonoids and foraminifers of Middle Triassic (Pelsonian) Jelovica Limestone Formation (Stara Planina Mts), Eastern Serbia. ![]()
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