[Show abstract][Hide abstract] ABSTRACT: In India, emergence of Ind2001 lineage of foot-and-mouth disease virus (FMDV) serotype O was recorded in the year 2001. After causing sporadic incidences, the Ind2001 lineage that re-surged in 2008 out-competed PanAsia from the field -during 2009 and continued its dominance during 2010 and 2011 as well. The lineage has diversified in due course of time, leading to two sub-lineages (Ind2001a and Ind2001b). The sub-lineage Ind2001a include isolates collected during 2001-2002 and sub-lineage Ind2001b is constituted largely by isolates collected during 2008-2012. The nucleotide substitution rate of sub-lineage Ind2001b was estimated at 6.58 × 10(-3) substitutions/site/year. The most stable PanAsia lineage is restricted only to few outbreaks. During 2011, emergence of a new genetic group with > 9% nucleotide divergence from rest of the lineages circulating in the country was detected and named as lineage Ind2011. Two specific amino acid substitutions at positions VP1- 36 (F) and VP2- 133 (T) were observed in the Ind2011 lineage. The new lineage at present is restricted only to southern states of the country. It is uncertain whether the emergence was triggered by immune pressure or due to a bottleneck in transmission or selected for higher fitness value. Six sites (4, 68, 83, 135, 138 and 209) in VP1 protein were identified to undergo episodic diversifying selection in serotype O field isolates. Both emerging and re-emerging lineages had appropriate antigenic match with currently used vaccine strain, INDR2/1975. Irrespective of genetic variability, the field isolates showed remarkable conservation at antigenically critical residues that might contribute to the observed antigenic stability. With the emergence of a new genetic group after a span of 10 years, the overall epidemiological scenario in the region is expected to change in the coming years.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 05/2013; 18. DOI:10.1016/j.meegid.2013.04.027 · 3.02 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The objective of this study was to investigate the endometrial expression of pro-inflammatory cytokines (IL1β, IL6, IL8 and TNFα) along with TLR4 and CD14 in normal and endometritic buffaloes. The genitalia were collected in the abattoir and divided into three groups as normal (gr. I=12), clinical endometritis (CE, gr. II=12) based on positive color reaction to white side test of uterine discharge and sub-clinical endometritis (SCE, gr. III=12) based on endometrial cytology (presence of ⩾5% PMNs) and histopathology. The equal numbers of genitalia were grouped into follicular and luteal stage in each group. Endometrial tissue scrapings were used for total RNA extraction and cDNA was transcribed and amplified by Real time PCR. The results showed several fold higher expression of all cytokine transcripts in CE (gr. II), whereas significant up-regulation of CD14 (1 to 2-fold), IL6 (15 to 36-fold), IL8 (8 to 14-fold) and TNFα (10 to 11-fold) mRNA was observed in SCE. This indicates that the evaluation of expression patterns of certain cytokines gene holds promise to diagnose the severity and degree of uterine inflammation.
Research in Veterinary Science 10/2012; 94(2). DOI:10.1016/j.rvsc.2012.09.008 · 1.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Differentiation of infected from vaccinated animals (DIVA) is essential for effective control of foot-and-mouth disease (FMD) by vaccination. The antibody response against FMD viral non-structural proteins (NSPs) has been used widely for this purpose. Among all the NSPs, the 3ABC polyprotein has been recognized as the most appropriate indicator for DIVA. In this study, mutated full-length 3ABC polyprotein was expressed in a prokaryotic system and monoclonal antibody against the recombinant protein was developed. A competitive ELISA (C-ELISA) for DIVA was standardized for different species of livestock animals using recombinant 3ABC and monoclonal antibodies. The diagnostic sensitivity and specificity of the assay were estimated by testing a panel of known serum samples consisting of sera from naive, vaccinated and infected animals as 86.9% with 66.4-97.2 (95%) confidence interval and 97% with 89.6-99.6 (95%) confidence interval respectively at 40% inhibition cut-off. The assay was validated further by testing sera from different livestock species collected at random from different parts of the country. The assay will provide a common method for testing sera from different species of livestock and wild animals. The C-ELISA is a sensitive and specific DIVA assay for FMD and can be used as a method for FMD control programme with vaccination.
[Show abstract][Hide abstract] ABSTRACT: Foot-and-mouth disease (FMD) is a highly contagious and transboundary viral disease of domesticated and wild
cloven-hoofed animals. Wide prevalence of the disease in Asia and Africa associated with huge economic loss to the
livestock farming and industry has increased the concern worldwide. The disease is a major threat to cattle, buffalo
(both milk and meat) and pig production in endemic countries and therefore considered to cause food insecurity, both
locally and globally. Currently, 6 serotypes of FMD virus (O, A, Asia-1, SAT-1,-2, and -3) are circulating globally, and
serotype C has not been recorded since 1995. In India, the disease is caused by serotypes O, A and Asia-1, of which
serotype O is responsible for most of the outbreaks. Emergence and re-emergence of FMD virus genotypes/lineages has
been detected in serotypes. Serotype A viruses have been continuously emerging in the nature necessitating frequent
replacement of the vaccine strains. The knowledge generated in epidemiology, diagnosis and surveillance of the disease
in the country has been instrumental in formulation and implementation of FMD Control Programme through regular 6
monthly vaccination with the aim to create disease free zones in India. The control programme, in operation since
X Plan, has resulted in progressive and substantial reduction in occurrence of the disease and DIVA reactors/converters
in vaccinated areas. The present review summarizes the disease, the causative agent, and epidemiology of FMD in India
and the world.
The Indian journal of animal sciences 02/2012; 82(2):2012. · 0.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Bluetongue virus serotype-1 (BTV-1) was isolated from Culicoides oxystoma vectors captured on livestock farms in two places of Gujarat, India. The viruses were isolated on BHK-21 cells, which produced characteristic BTV-related cytopathic effects between 24 and 48 h post-infection. Virus antigen was demonstrated in infected cells at different passage by a BTV-specific sandwich ELISA. Further, polyacrylamide gel electrophoresis and silver staining of viral genomic RNA revealed ten double-stranded RNA segments characteristic of BTV. Serotype of the isolates was identified by virus neutralization and PCR coupled with sequencing. The isolates were designated as SKN-7 and SKN-8 and their genome segment-2 (VP2) were sequenced. Phylogenetic analyses revealed very close relationship between them although they are not identical. SKN-8 showed closer relationship with a recently isolated BTV-1 from goat. Bluetongue virus was earlier isolated from Culicoides in adjacent state more than 20 years ago, although the serotype of the virus was not determined.