Serological and clinical surveillance studies to validate reported foot-and-mouth disease free status in Tsirang district of Bhutan

摘要: Serological and clinical studies were conducted between March 2009 August 2010 to validate the foot-and-mouth disease free status of Tsirang district Bhutan as determined by country's passive surveillance system. Randomised (first survey) targeted (third samplings, with subsequent follow-up samplings (second fourth), on FMD-susceptible animals detect at a design prevalence 25% 20% individual animal-level village-level, respectively. Sera from cattle, goats, pigs, sheep tested for presence non-structural protein (NSP) antibodies using two commercial (PrioCHECK ® FMDV NS CHEKIT ®-FMD-3ABC-bo-ov) one in-house NSP kit (c-ELISA, AAHL, Australia). The overall seropositivity (all species) was 3% (95% CI: 1.7, 4.8) 3.5% 2.1, 5.4), randomised surveys, Except goat first survey, none small ruminants pigs had antibodies. seropositives surveys distributed among 13 16 20 villages sampled, All repeat testing initial seropositive their herd mates, both third negative in tests 6-8 months later. Using hypergeometric exact probability formula two-stage analyses, results enabled rejection null hypothesis supported conclusion that population minimum expected 95.53% 99.46% confidence levels, Clinical also showed absence or signs suggestive FMD. few likely be false positives due factors such imperfect specificities possible NSP-residues vaccines. study has paved way initiation zoning approaches progressive control FMD Bhutan.