Seroprevalence of Foot and Mouth Disease in apparently healthy beef cattle in Uganda post the 2021 outbreak

Abstract

Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hoofed animals caused by a picornavirus. There are 7 known serotypes (O, C, A, SAT1, SAT2 and Asia) and more than 60 subtypes of the FMD virus. FMD causes enormous economic losses including reduced animal productivity and restrictions on international trade in animal products. In Uganda, FMD is endemic and caused by mainly O, A, SAT 1, and SAT2 serotypes. The outbreaks are mainly controlled by ring vaccination and restriction of animal movement. These control methods are sometimes not efficient due to lack of regular surveillance. Information on the seroprevalence of FMDV in animal herds post outbreak response is not available to guide policy makers on when to lift quarantine in affected districts. A study was therefore conducted to assess the effectiveness of the 2021 FMD outbreak response in Western Uganda following lifting of the quarantine restrictions. As part of routine herd health checks, blood samples were extracted from sixty-eight apparently healthy beef cattle. Of these, 46 were from Nshaara ranch and 22 from Mbarara city abattoir. The samples were tested for the presence of specific FMDV antibodies using Solid-Phase Competitive Enzyme-Linked Immunosorbent Assay. Overall, out of 68 samples, 51 (75%) tested positive for FMDV. Out of 46 samples taken from Nshaara ranch, 43 (93.5%) were positive and out of 22 samples from Mbarara City abattoir 8 (36.4%) were positive. The study revealed a concerningly high seropositivity of apparently health animals to FMDV antibodies possibly due to early lifting of the quarantine, weak enforcement of control measures or lack of incentive and resources to control the disease. Therefore, the Uganda national outbreak preparedness and response unit should move quickly to put in place a coordinated, effective, and functional preparedness and response mechanism whenever there are such disease outbreaks.