Seroprevalence of Bluetongue Virus in small ruminants in Balochistan province, Pakistan
Bluetongue (BT) caused by bluetongue virus (BTV) is a vector borne disease of small ruminants that has the potential to spread across international borders. Despite large populations of susceptible animals and borders with BTV endemic countries, little is known of the disease burden and prevalent serotypes in the province of Balochistan in Pakistan. We conducted a cross sectional study to determine seroconversion and prevalent serotypes in selected districts of the province using a competitive enzyme linked immunosorbent assay (cELISA) and real time polymerase chain reaction (RT PCR) Sera (n 876) were collected from clinically healthy sheep and goats originating from the districts of Quetta (n 300) Mastung (n 201) Killa Saifullah (n 75) and Kech (n 300) None of the study herds (n 97) were seronegative for BTV, and at the individual level, the overall prevalence of BTV seroconversion was 47.26% (n 414/876, 95% CI 43.92% 50.63% A higher percentage of goats (50.87% 95% CI 45.99% 55.73% were seropositive for anti VP7 immunoglobulins (IgG) than sheep (44.21% 95% CI 39.81% 48.70% Odds ratios of seroconversion for goats were associated with breed type (kh2 16.84, p .01) parity (kh2 23.66, p .00) and presence of vector (kh2 2.63, p .10) whereas for sheep, it was associated with breed type (kh2 13.80, p .01) and parity (kh2 53.40, p .00) Serotype 8 was the most prevalent (26.82% 95% CI 14.75% 43.21% followed by an equal prevalence of serotypes 2 and 9 (7.31% 95% CI 1.91% 21.01% To the best of our knowledge, this is the first study conducted in Balochistan province and the results indicate that there is a necessity to initiate intervention strategies to control BT disease burden not only in this region of Pakistan but also in adjacent areas of the neighbouring countries, Iran and Afghanistan.
Transboundary and emerging diseases