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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 ≥1.8 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. [ABSTRACT FROM AUTHOR]

Summary: Foot‐and‐mouth disease (FMD) is an important transboundary disease with substantial economic impacts. Although between‐herd transmission of the disease has been well studied, studies focusing on within‐herd transmission using farm‐level outbreak data are rare. The aim of this study was to estimate parameters associated with within‐herd transmission, host physiological factors and FMD virus (FMDV) persistence using data collected from an outbreak that occurred at a large, organized dairy farm in India. Of 1,836 regularly vaccinated, adult dairy cattle, 222 had clinical signs of FMD over a 39‐day period. Assuming homogenous mixing, a frequency‐dependent compartmental model of disease transmission was built. The transmission coefficient and basic reproductive number were estimated to be between 16.2–18.4 and 67–88, respectively. Non‐pregnant animals were more likely to manifest clinical signs of FMD as compared to pregnant cattle. Based on oropharyngeal fluid (probang) sampling and FMDV‐specific RT‐PCR, four of 36 longitudinally sampled animals (14%) were persistently infected carriers 10.5 months post‐outbreak. There was no statistical difference between subclinical and clinically infected animals in the duration of the carrier state. However, prevalence of NSP‐ELISA antibodies differed significantly between subclinical and clinically infected animals 12 months after the outbreak with 83% seroprevalence amongst clinically infected cattle compared to 69% of subclinical animals. This study further elucidates within‐herd FMD transmission dynamics during the acute‐phase and characterizes duration of FMDV persistence and seroprevalence of FMD under natural conditions in an endemic setting. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease (FMD) is a highly contagious and globally significant viral disease principally of cloven-hoofed livestock species. The present study describes the results of molecular epidemiologic investigation of FMD in pigs across various states of India between 2008 and 2014. During this period, a total of 37 clinical epithelial samples (vesicle/foot/snout epithelium) of FMD-suspected pigs were tested in a serotype differentiating antigen detection ELISA and samples found negative were further subjected to multiplex reverse transcription-polymerase chain reaction (mRT-PCR). A total of 29 (78.37%) samples were found positive for serotype O in antigen detection ELISA and 8 ELISA-negative samples were subsequently found positive for serotype O in mRT-PCR. The VP1 region-based phylogenetic analysis demonstrated the involvement of O/ME-SA/Ind2001 lineage in the outbreaks. The pig isolates clustered with the contemporary virus isolates collected from bovine indicating a close genetic relationship and therefore signifying inter-species transmission during the outbreaks. [ABSTRACT FROM AUTHOR]

The yak and mithun husbandry in India is confronted with several challenges including the prevalence of foot-and-mouth disease (FMD). The present study was initiated to investigate FMD outbreaks in semi-domesticated mithun and yak population in various parts of India. A total of 64 clinical samples (vesicle/tongue/foot epithelium/fluid) from mithun and 6 from yak were collected from suspected FMD outbreaks during 2008-2013. Supernatants of the homogenized clinical samples were tested in a serotype discriminating antigen detection ELISA and ELISA-negative samples were further subjected to multiplex reverse transcription-polymerase chain reaction (mRT-PCR). A total of 45 mithun samples and only 1 yak sample were found positive for serotype O in antigen detection ELISA. A total of 12 ELISA-negative samples from mithun and 4 from yak were later on found positive for serotype O in mRT-PCR. The phylogenetic analysis based on VP1 genome indicated the involvement of both O/ME-SA/PanAsia and O/ME-SA/Ind2001 lineages of serotype O in those outbreaks. These viruses were genetically similar to those contemporary virus isolates responsible for FMD in domestic livestock indicating a situation of virus sharing among different species of domestic and semi-domestic animals. Thus, mithuns and yaks should be synchronously considered and targeted along with cattle for the effective control of the disease in the country. [ABSTRACT FROM AUTHOR]

Small ruminants (sheep and goats) are susceptible to foot-and-mouth disease (FMD), while studies with due emphasis on their role in the disease epidemiology have been meagre. The present study summarizes the results of clinico-molecular investigation of FMD in sheep and goats across several states of India during 2008–2014, where a total of 51 clinical epithelial tissue samples (vesicle/tongue/gum/foot epithelium) from sheep and 78 from goats were found positive for FMD virus (FMDV) serotype O in serotyping ELISA and multiplex reverse transcription-PCR. The VP1 region-based phylogenetic analysis demonstrated the involvement of O/ME-SA/Ind2001 lineage of serotype O virus in the outbreaks. The field viruses recovered from both small and large ruminant population during the same time period showed a close genetic relationship suggesting frequent inter-species transmission of virus. Since the disease often remains clinically camouflaged in small ruminants, the animals silently infected with FMD may pose potential threats to the in-contact livestock. Regular vaccination combined with surveillance and monitoring of protective antibody status in these species is therefore crucial to the effective control of FMD in the country. [ABSTRACT FROM AUTHOR]

A total of 41 clinical samples (vesicle/tongue/foot/nasal epithelium) from Indian gaur, deer, spotted deer, nilgai, chowsinga, bison, black buck, elephant, sambar deer were collected in 50% phosphate buffered saline/glycerol medium (pH-7.5) during suspected FMD outbreaks. Supernatants of homogenized clinical samples were used in a serotype differentiating antigen detection ELISA and samples found negative were further subjected to multiplex PCR (mPCR). A total of 3/11 (27.2%) samples from Indian gaur, 2/7 (28.5%) chital deer, 5/5 (100%) nilgai, 2/2 (100%) black buck were found positive for serotype O in antigen detection ELISA. A total of 3 ELISA-negative samples from spotted deer, 2 from bison and 2 from sambar deer were found positive for serotype O in mPCR. The VP1 region-based phylogenetic analysis indicated the involvement of both O/ME-SA/Ind2001 and PanAsia lineage of serotype O in the outbreaks. The wildlife species infected with FMD may pose further threat to the surrounding domestic livestock. [ABSTRACT FROM AUTHOR]