Epidemiological Investigation of Bovine Ephemeral Fever Outbreaks in Israel

Abstract

Outbreaks of bovine ephemeral fever (BEF) occurred in Israel in 1990, 1999, and 2004. 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. 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 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°C in late autumn. The herd incidence of the disease reached 78.4%, 97.7%, and 100% in 1990, 1999, and 2004, respectively. 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 average sero-positivity to BEF in 1999 was 39.5%, which matched the morbidity rate. 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. 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. All affected cattle were over the age of 3 months. It is hypothesized that mosquitoes and not Culicoides spp. are the vectors of the BEF virus in Israel.

Determinants of bovine ephemeral fever outbreak during 2013, in Qazvin Province, Iran

“…and 100%, respectively [19]. Momtaz et al reported animal level incidence in the province of Khuzestan, Iran, to be higher than what we observed in this study [5], whereas others [21] reported similar findings to ours.…”

“…It is considered as an endemic disease in Africa and most areas of the Middle East [18,19] being reported from Jordan, Syria, Iraq, Turkey, and Iran. In some African and Asian countries, the epidemic form of the disease has been reported as well [5,16].…”

Epizootic haemorrhagic disease virus type 7 infection in cattle in Israel

“…bef virus ( befv ), which was formerly thought to appear cyclically in Israel every seven to 15 years, reappeared in 1999, 2000, 2001 and 2004 (Yeruham and others 2002, 2003a, b, 2005). Akabane virus, the causative agent of the arthrogryposis and hydrancephaly/microencephaly syndromes, that appeared in the northern valleys of Israel in 1969/70 (Markusfeld-Nir and Mayer 1971, Kalmar and others 1975, Shimshony 1980), appeared again in 2001 and 2003 (Brenner and others 2004a, b).…”

Assessment of the molecular epidemiology of bovine ephemeral fever in Turkey

“…It has also been reported in australia (FINLaISON et al, 2010;St GeOrGe, 1997) and in most countries of africa and asia (BakhSheSh and aBDOLLahI, 2015;hSIeh et al, 2005;MOMtaZ et al, 2012;YerUhaM et al, 2002;ZaGhaWa et al, 2016) and Japan (katO et al, 2009;NIWa et al, 2015;OGaWa, 1992). In Turkey, BEF infection was first recorded in 1985 (GIrGIN et al, 1986).…”