doi:10.1038/nindia.2011.28 Published online 28 February 2011
The human metapneumovirus (hMPV) has been continuously evolving in the Indian subcontinent, according to a new study conducted on patients suffering from acute respiratory tract infection (ARTI), a condition caused by the virus. The study emphasizes the need for a country-wide investigation to provide a better understanding of the prevalence, epidemiology and evolution of the virus.
To study the prevalence and genomic diversity of hMPV strains, the researchers studied ARTI patients reporting in the outpatient departments of hospitals in Kolkata, Eastern India. Around 5% of the clinical samples tested positive for hMPV.
In genetic profiling, G sequences of these strains showed higher diversity at the nucleotide and amino acid level. In contrast, less than 10% variation was observed in the F gene. Sequence analysis also revealed changes in the position of stop codon in the G protein, which resulted in polypeptides of variable length (217–231 aa).
"This is the first report on the genetic variability of the G and F gene of hMPV strains from India, which clearly shows that the G protein of hMPV is continuously evolving," say the researchers.
Only one other study has investigated the genetic heterogeneity of hMPV strains from Northern India, which makes it difficult for the researchers to assess the current status of heterogeneity of hMPV strains in the country. They urge the need for more epidemiological studies for this rare pneumonia-causing virus.