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Foot-and-mouth disease (FMD) is, arguably, the animal disease with the most devastating global economic impact owing in part, to the severe trade restrictions imposed upon affected countries and regions. South Asia is one of the regions where widespread lineages of the FMDV virus (FMDV) have emerged. Here, we performed an integrative phylogenetic analysis of all FMDV serotypes (A, O and Asia-1) circulating in southern Asia, including viral sequences collected until 2013. Our results describe the occurrence of FMD caused by different serotypes and lineages, focusing in the cycles where a specific lineage predominates within a region for a protracted period and then are rapidly or progressively replaced by an emergent or re-emergent strain that is introduced from an adjacent region. Transmission between the two main regions in southern Asia (the Indian subcontinent and the region comprised by Afghanistan, Iran and Pakistan) has been limited. Results of time divergence estimation of lineages that currently circulate in this region indicate that the most recent common ancestor of endemic lineages are: 1992 [1989-1995] for lineage O/PanAsia; 1997 [1995-1999] for PanAsia2; 2001 [1998-2004] for O/Ind2001; 2001 [2000-2002] for A/Iran-05; 1990 [1988-1991] for A/G-18 (G-VII); 2003 [2000-2006] for Asia-1 Sindh08 and 2002 [1999-2004] for Asia-1 G-VIII. We estimated the mean of the overall substitution rate of the VP1 coding region (substitution/site/year) for serotype O (5.95 × 10 -3 ), serotype A (1.19 × 10 -2 ) and serotype Asia-1 (3.08 × 10 -3 ). The potential factors driving the lineage turnover are discussed. Our results provide insights into the ecological and evolutionary factors driving the emergence of FMDV., (© 2017 Blackwell Verlag GmbH.)

Foot and mouth disease virus (FMDV) serotype Asia1 was first identified in India in 1951 and since then causing significant proportion of FMD outbreaks in the country. In this paper genetic analysis of 219 isolates from India collected over a period of 48 years is described. Bayesian approach was used to estimate the date of divergence and evolutionary rate. Phylogenetic analysis indicated the circulation of three lineages (B, C and D) of which lineage B formed one genotype (I) which was prevalent during 1964-2000. Genotype II constituted by lineage C and D has been in circulation since 1979 till date. We observed dramatic form of clade turnover in serotype Asia1 in India. The time scale analysis indicated that the most recent common ancestors for Indian Asia1 strains existed around 77 years ago. The evolutionary rate of serotype Asia1 viruses (genotype II) from India was estimated at 5.871×10(-3) substitutions per site, per year. We observed several connections in our phylogeographic analysis indicating intense flow of virus among states. The antigenically critical sites were frequently substituted and positive selection was evident at many sites. Maximum likelihood analysis suggested that the strains circulating in the country since 2005 were different from the genetic groups (I-VII) identified earlier and designated here as Group VIII., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The phylogenetic analysis of VP1 sequences of the 39 type O foot and mouth virus (FMDV) isolates collected from different regions of India during the year of 2001-12 revealed that all isolates belonged to the Middle East - South Asia (ME-SA) topotype. Based on the amount of divergence among the isolates, the viruses were further classified into three distinct lineages namely Ind 2001, PanAsia and PanAsia-2 as well as a minor, unnamed group. Ind 2001 lineage viruses accounted for most of the current type O outbreaks. At the nucleotide level these isolates showed a divergence of 2% to 14% with an average sequence variation of ~9.9%. The serological spectrum of the current vaccine strain was studied by using bovine vaccinate serum (BVS) raised against O/IND/R2/75. All the current field isolates (n=24) were homologous ('r' value 0.4 to 1.0) to the vaccine strain. Examination of the amino acid sequences for selection pressure revealed the positive selection at amino acid sites 13 and 45., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Global epidemiological analysis is vital for implementing progressive regional foot-and-mouth disease control programmes. Here, we have generated VP1 region sequences for 55 Indian type A outbreak strains and have included complete VP1 sequences from 46 other countries to obtain a comprehensive global phylogeographical impression. A total of 26 regional genotypes within three continental topotypes, based on a 15% nucleotide divergence cut-off criterion, could be identified. These genotypes correlated with distinct evolutionary lineages in the maximum-likelihood phylogeny. During the last decade, ten genotypes have been in circulation the world over and it was evident that no type A strain has transgressed the continental barriers during this period. A single genotype (genotype 18) within the Asia topotype has been circulating in India with neither any incursion nor any long distance movement of virus out of the country during the last ten years, although close genetic and epidemiological links between viruses from Bhutan and India were revealed.

Background & Objectives: With the emergence of a new reassortant influenza A H1N1 virus that caused the 2009 pandemic it was felt necessary that pigs should be closely monitored for early detection of any influenza virus infection. Therefore, we investigated disease outbreaks with clinical history suggestive for swine influenza reported to our laboratory by owners of affected pig farms in Uttar Pradesh., Methods: Detection of swine influenza A virus (SIV) was attempted by isolation in embryonated chicken eggs. Presence of virus was detected by haemagglutination (HA) test and RT-PCR for amplification of different gene segments, cloning and sequencing. BLAST analysis of sequence data, phylogenetic analysis and mutation analysis based on HA, NA and matrix genes was done., Results: SIV could be isolated from one farm and all eight gene segments amplified by RT-PCR. BLAST analysis of partial nucleotide sequences and phylogenetic analysis using nucleotide sequence of HA (601 nt), NA (671 nt) and M (1031 nt) genes indicated close genetic relationship of the Indian swine isolate (A/Sw/UP-India-IVRI01/2009) with human pandemic 2009 (H1N1). The HA gene showed close relationship with the viruses of "North American Swine" lineage, whereas the NA and M genes clustered with the viruses of "Eurasian Swine" lineage, indicating a novel HA-NA reassortant. The remaining of 5 genes (NP, PA, PB1, PB2 and NS) belonged to "North American Swine" lineage., Interpretation & Conclusions: This is perhaps the first report describing swine influenza among Indian pigs caused by an influenza A H1N1 virus sharing close homology with the human pandemic (H1N1) 2009 virus. Further reassortment with circulating influenza viruses must be closely monitored.

Genotype inclusive grouping of Indian type A isolates as observed in 1D region based phylogeny was distorted at complete L(pro) region, where the VP3(59)-deletion group lineages of genotype VII clustered away from both genotypes VII and VI, confirming its uniqueness and independent evolution of L(pro) and 1D region. Akin to the 1D region, this deletion group is gradually diverging genetically even at L region forming more number of lineages and inter-lineage distance at L region is considerably more than that for 1D region. The deletion group is restricted to India only as none of the exotic sequences clustered within this group. Notably, L protein exhibited variability comparable to external capsid proteins as evident from its high d(N)/d(S) ratio (0.105), number of variable amino acid positions (41%), low Ts/Tv ratio (3.47) and alignment revealed N-terminal region, beta2 sheet and C-terminal extension to be extremely variable. Basic residues at P1, P3 and only leucine at P2 were predicted to provide an optimum autocatalytic cleavage site at L/P1 junction. All of the eight sites identified to be under positive selection revealed aa substitutions of varied physicochemical properties and at two positions lineage specific signatures were observed, which supports the contention that lineages are evolving under differential selection pressure to adapt to the varied ecological environment.

The recent type A foot and mouth disease virus field isolates recovered in India are shown to be antigenically quite divergent from the in-use vaccine strain (IND 17/82), warranting the selection of a suitable vaccine strain which can cover this diversity in antigenic spectrum. In earlier studies employing neutralization test with anti-146S rabbit sera raised against eight candidate vaccine strains, IND 81/00 and IND 40/00 belonging to genotype VII were found to offer the best antigenic coverage. In order to assess the credibility of IND 81/00 and IND 40/00 as vaccine strains, 17 recent isolates received during 2005-2006 and representative isolates from older genotypes were subjected to two-dimensional micro-neutralization assay using bovine convalescent serum (against IND 81/00 and IND 40/00) and bovine vaccinate serum (against IND 40/00). From the results it is evident that both the isolates IND 81/00 (antigenic relationship 'r-value' >0.40 with 86% of isolates) and IND 40/00 ('r-value' >0.40 with 78% of isolates) show nearly equal antigenic relatedness with the recent field viruses and hence both of these are effective vaccine candidates in present context. Though very limited in its extent, these useful data obtained with antisera raised in homologous host system are logical extension of the on going quest for the appropriate vaccine strain and circumvents species disparities in the immune recognition of epitopes.

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]

Foot-and-mouth disease viruses are often restricted to specific geographical regions and spread to new areas may lead to significant epidemics. Phylogenetic analysis of sequences of the VP1 genome region of recent outbreak viruses from Libya and Saudi Arabia has revealed a lineage, O-Ind-2001, normally found in the Indian subcontinent. This paper describes the characterization of field viruses collected from these cases and provides information about a new real-time RT- PCR assay that can be used to detect viruses from this lineage and discriminate them from other endemic FMD viruses that are co-circulating in North Africa and western Eurasia. [ABSTRACT FROM AUTHOR]

Complete 1D gene sequences of 13 Indian foot-and-mouth disease virus (FMDV) type C field isolates and a vaccine strain (C-Bombay/64) were determined. All the field isolates showed a greater genetic homogeneity (95–100%) among themselves and were 19.7–21.2% divergent from the vaccine strain. In the phylogenetic analysis, the Indian field isolates formed a separate lineage (lineage VII) different from the previously identified six lineages (lineage I–VI) in type C FMDV [J. Virol. 66 (1992) 3557]. The vaccine strain was grouped with European lineage (lineage II). Comparison of the deduced amino acid sequences of antigenic sites A and C of field isolates showed no significant variation from the vaccine strain. One-way serological relationship determined in ELISA showed antigenic closeness of the field isolates with C-Bombay/64. [Copyright &y& Elsevier]