A further outbreak of classical swine fever in indigenous pigs in Kurigram district, Bangladesh
- 25 February 2020
- journal article
- research article
- Published by Hindawi Limited in Transboundary and Emerging Diseases
- Vol. 67 (5), 1922-1929
- https://doi.org/10.1111/tbed.13527
Abstract
Deaths of native scavenging pigs were reported in mid‐November 2015 at Nageswari subdistrict, Kurigram district of Bangladesh. The investigation for a suspected classical swine fever (CSF) outbreak was accomplished via a joint outbreak investigation team from Department of Livestock Services (DLS) and Food and Agriculture Organization, Emergency Center for Transboundary Animal Disease (FAO‐ECTAD), Bangladesh. Out of 592 pigs, 396 were infected and among them 263 died. The attack rate and case fatality rate were 66.9% and 66.4%, respectively. The epidemic curve constructed using the data captured from the CSF outbreak site was nearly bell‐shaped, indicating a point source epidemic. The basic reproduction numbers (R0) were estimated to be 1.6 (95% Confidence interval [CI]: 1.5−1.7) and 1.5 (95% CI: 1.3−1.7) based on attack rate and exponential growth rate methods, respectively. Adult pigs showed signs of high fever, staggering gait, and depression; whereas piglets either died without any premonitory signs, or purulent exudates in the eyes were observed. Post mortem examination was carried out on a six‐month old piglet. The necropsy findings included were swollen lymph nodes deep red in color, and hemorrhages on serous and mucous membranes of the intestinal organs together with button‐like ulceration in the intestines. Nasal swabs and tissue samples (spleen, lung, and liver) were tested using real time reverse transcriptase polymerase chain reaction (RT‐qPCR) and found to be positive for CSF virus. One step RT‐PCR was used to amplify 1148 base pair of E2 gene in extracted RNA and was sequenced using standard Sanger’s sequencing. Phylogenetic analysis revealed the virus as genotype 2.2 that clustered with CSF virus sequences from Bangladesh and India. This is only the second report of a CSF outbreak in Bangladesh. CSF appears to be an emerging transboundary disease in this country. A special program for controlling swine diseases is needed since pigs are being reared by marginalized communities of Bangladesh to provide livelihoods and food security.This publication has 16 references indexed in Scilit:
- MEGA7: Molecular Evolutionary Genetics Analysis Version 7.0 for Bigger DatasetsMolecular Biology and Evolution, 2016
- Cultural and Economic Motivation of Pig Raising Practices in BangladeshEcohealth, 2015
- Emergence of 2.1. subgenotype of classical swine fever virus in pig population of India in 2011Veterinary Quarterly, 2014
- Dynamics of Japanese Encephalitis Virus Transmission among Pigs in Northwest Bangladesh and the Potential Impact of Pig VaccinationPLoS Neglected Tropical Diseases, 2014
- Validation of a Real Time PCR for Classical Swine Fever DiagnosisVeterinary Medicine International, 2014
- Phylogenetic analysis using E2 gene of classical swine fever virus reveals a new subgenotype in ChinaInfection, Genetics and Evolution, 2013
- CP7_E2alf oral vaccination confers partial protection against early classical swine fever virus challenge and interferes with pathogeny-related cytokine responsesVeterinary Research, 2013
- Challenge of Pigs with Classical Swine Fever Viruses after C-Strain Vaccination Reveals Remarkably Rapid Protection and Insights into Early ImmunityPLOS ONE, 2012
- Genetic typing of recent classical swine fever isolates from IndiaVeterinary Microbiology, 2010
- Clinical Signs and Epidemiology of Classical Swine Fever: A Review of New KnowledgeThe Veterinary Journal, 2003