Investigation of foot-and mouth disease outbreak in a pig farm at Kollam district of Kerala, India

Abstract

The present paper describes the investigation of foot-and-mouth disease (FMD) outbreak in a private pig farm at Kotty in Kollam district of Kerala during October 2013. During the clinical phase, severe vesicular lesions on snout and skin around the coronary bands were observed in pigs. A total of 48 serum samples and 12 clinical samples (ruptured snout epithelia) were collected. All serum samples were subjected to indirect 3AB nonstructural protein (NSP) ELISA and liquid phase blocking (LPB) ELISA. In 3AB NSP ELISA, all serum samples were found positive for NSP antibodies indicating infection. In LPB ELISA, 42 of 48 (87.5%) pigs were found to have protective log10 antibody titre of ³1.8 against FMD virus serotypes O, A and Asia 1. All the clinical materials were found positive for serotype O in antigen detection ELISA as well as in multiplex reverse transcription-polymerase chain reaction (mRT-PCR). In VP1 region-based phylogenetic analysis, the serotype O isolates causing the outbreak were found to conglomerate within Ind2001 lineage. Pigs infected with FMD may pose rigorous threat to other susceptible domestic livestock as they exhale enormous quantity of virus. As a consequence, they should be included under prophylactic vaccination and surveillance programmes ongoing in the country.