Serological survey of ruminants in some Caribbean and South American countries for type-specific antibody to bluetongue and epizootic haemorrhagic disease viruses

Abstract

The results of a serological survey of ruminant livestock in some countries of the Caribbean and South America for type-specific antibody to bluetongue virus are reported. Using the microneutralisation test with the international serotypes 1 to 22 of bluetongue virus, antibodies to several types were detected. Analysis of the data indicated that in 1981-82 bluetongue virus types 6, 14 and 17, or viruses closely related to them, were infecting ruminants in this region of the world. Antibody to the related virus of epizootic haemorrhagic disease (serotype 1) was also detected in cattle. The difficulty in interpreting the epidemiological significance of data generated by a serological survey of this kind is discussed.

Bluetongue virus and epizootic haemorrhagic disease of deer virus serotypes in northern Colombian cattle

“…The presence of antibodies to BT types 12, 14 and 17 and EHD types 1 and 2 in northern Colombia is consistent with previous findings of antibody to the same types of BT, and EHD type 2 in the Caribbean islands, and types 14 and 17 and EHD types 1 and 2 in Guyana and Suriname (Gumm et al 1984). These authors also found antibodies to BT types 1 and 6.…”

“…EHD virus has been isolated from cattle in the United States and Canada (Sellers, 1981). In the American tropics antibody to EHD has been detected in cattle in the Caribbean islands, Guyana and Suriname (Gumm et al, 1984) and Costa Rica (Homan & Taylor, unpublished observations). EHD and BT viruses are antigenically differentiable by neutralization tests, but in tests detecting group-specific antibody, such as agar gel precipitation, varying degrees of cross-reaction may occur (Jochim, 1976;Della-Porta, McPhee & Parsonson, 1983).…”

“…Recent studies in the Caribbean, Central and South America indicate high prevalence of BT group-specific antibody in the American tropics, but there is no report of clinical manifestations of the infection (Gibbs et al 1983 a;Gumm et al 1984;Homan et al 1984). EHD virus has been isolated from cattle in the United States and Canada (Sellers, 1981).…”

“…EHD and BT viruses are antigenically differentiable by neutralization tests, but in tests detecting group-specific antibody, such as agar gel precipitation, varying degrees of cross-reaction may occur (Jochim, 1976;Della-Porta, McPhee & Parsonson, 1983). In the absence of acute cases of clinical BT and EHD for virus isolation attempts and of adequate facilities for orbivirus isolation and typing, a serological approach may yield valuable indicators of the virus types circulating in an area (Gumm et al 1984). Mature animals that have been exposed to reinfection with several BT types may develop broadly cross-reactive neutralizing antibodies, making difficult an interpretation of the virus types present.…”

“…Mature animals that have been exposed to reinfection with several BT types may develop broadly cross-reactive neutralizing antibodies, making difficult an interpretation of the virus types present. However, young animals experiencing their first BT infection usually develop a clear monospecific response to the infecting virus type (Jeggo, Gumm & Taylor, 1983;Gumm et al 1984). Sequential sampling can identify the time period in which infection occurs.…”