Pandemic and seasonal influenza viruses among patients with acute respiratory illness in Kashmir (India)

Sheri-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, India.
Influenza and Other Respiratory Viruses (Impact Factor: 2.2). 05/2011; 5(6):e521-7. DOI: 10.1111/j.1750-2659.2011.00261.x
Source: PubMed


With the emergence of pandemic influenza A (2009A/H1N1) virus in India, we sought to determine the prevalence and clinical presentations of seasonal and pandemic influenza viruses among acute respiratory illness (ARI) patients from Srinagar, a temperate climate area in northern India, during the peak winter season.
Combined throat and nasal swabs, obtained from 194 (108 male) presenting with ARI from January to March 2010 (Week 53-week 10), were tested by RT-PCR for influenza A and B, including 2009A/H1N1 viruses. HA1 gene of selected 2009A/H1N1-positive samples was sequenced, and phylogenetic analysis was carried out.
Twenty-one (10·8%, age 15-80 years, median age 40 years) patients tested positive for influenza viruses: 13 (62%) for 2009A/H1N1 virus, 6 (28·5%) for seasonal influenza A (H3N2), and 2 (9·5%) for influenza B. Twelve of the 13 patients with 2009A/H1N1 presented with febrile ARI, and eight had associated comorbidities. All of the patients recovered. Phylogenetic analysis of HA gene (n = 8) revealed that all strains from Srinagar clustered in 2009A/H1N1 clade seven along with the other 2009A/H1N1 strains from India. Amino acid substitutions in the HA protein defining clade seven (P83S, S203T, and I321V) were found in almost all isolates from Srinagar.
Both seasonal and 2009A/H1N1 viruses appear to be associated with ARI in Srinagar. The 2009A/H1N1 in Srinagar is genetically similar to globally circulating clade 7 strains, with unique signature sequences in the HA gene. Further investigations into ascertain the role of these mutations in possible alteration of the virulence and transmissibility of the virus are needed.

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Available from: Parvaiz A Koul, Sep 24, 2014
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    • "A medical team (consisting of 4 physicians and 5 laboratory personnel of influenza Laboratory of the SKIMS) visited the area during May 14-23, 2011. The clinical features of those fulfilling the criteria of ILI (defined by fever >38°C and a cough or sore throat) were recorded on a predefined questionnaire5. A total of 526 persons (age 1-75 yr, median 20 yr) with ARI were screened and throat/nasal swabs were obtained from 84 consecutive consenting patients (age 1-70 yr, median 7 yr) with ILI for influenza testing and transported to the Microbiology Laboratory at the All India Institute for Medical Sciences (AIIMS), New Delhi. The patients with ILI had significantly higher frequency of fever and chills (P<0.0001, "
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