Serological and Epidemiological Studies of Parapoxvirus Infection in Cattle in Ishikawa Prefecture

Abstract

A survey of antibodies against parapoxvirus species bovine papular stomatitis virus (BPSV) was conducted by agar gel immunodiffusion (AGID) test on 750 serum samples collected from cattle in Ishikawa Prefecture, Japan, in 2007. On farms, 0-21.9% dairy cattle and 8.3-33.3% beef cattle were seropositive, but the difference was not significant. The positive reaction rate was significantly higher in dairy cattle reared on public pastures (33.3-82.4%) than in dairy and beef cattle reared on farms. Among dairy cattle on farms, the positive reaction rate was significantly higher in cattle reared on public pastures and in cattle introduced from other prefectures than in cattle that were neither reared on pastures nor introduced from other prefectures. The same serum samples were tested for antibodies against orf virus (ORFV) by AGID, and the positive reaction rate for ORFV was almost the same or less than that for BPSV, and the immunodiffusion line on the gel was weaker for ORFV. There was no correlation between positive reaction rates in cattle and grazing on public pastures that geographically overlap with the habitat of Japanese serows (Capricornis crispus), which are also hosts of parapoxvirus. These results suggest that the risk of BPSV infection is higher for dairy cattle reared on pastures than on farms, but the risk of infection due to grazing on pastures inhabited by Japanese serows seems to be low.

Review of critical factors affecting analytical characteristics of serological and molecular assays

“…To assess the ASp of the prototype Cp 10 ELISA, sera collected from sheep that had been experimentally infected with orf virus (a parapoxvirus known to cause cross-reactivity in the agar gel immunodiffusion [17] and indirect immunofluorescence antibody tests [18,19]) were evaluated. In addition, sera collected from cattle in Japan that had been naturally exposed to parapoxviruses (orf or bovine papular stomatitis viruses), as determined by agar gel immunodiffusion (20), were also tested. The lack of correlation between the data demonstrated an absence of cross-reactivity (exclusivity) between the recombinant capripoxvirus protein and parapoxvirus antigens (Fig.…”

Establishment of an on-site diagnostic procedure for detection of orf virus from oral lesions of Japanese serows (<i>Capricornis crispus</i>) by loop-mediated isothermal amplification

“…Previous serological surveys revealed seroprevalence in Japanese serows from 1981 to 1985 of 76/579 (13%) [30], but then, it increased to 40/167 (24%) from 1984 to 1999 [10, 11]. Wild Japanese serows sometimes appear in cattle and sheep pastures in certain areas [4, 13]. These overlapping areas could increase the risk of pathogen transmission from domestic animals to free-ranging serows, and vice versa .…”