Influenza A(H1N1)pdm09 cases in sub-Himalayan region, 2014-2015 India.

Current influenza A(H1N1)pdm09 strain severely involved many parts of the country. The study was conducted to analyze the clinicoepidemiological trend of influenza A(H1N1)pdm09 cases from October 2014 to March 2015. Samples processing was done as per the Center for Disease Control guidelines. A total of 333 specimens were processed out of which influenza A(H1N1)pdm09 constituted 24% (81) of total, 5% (18) cases were seasonal influenza A virus strains. Mean age group involved was 49 years with case fatality rate of 20%. Patients died were 63% males and 44% had comorbidities, and among them, 38% patients died within 24 h of hospitalization. The mean age of comorbid patients who died was 59 years; whereas the mean age of patients died having no co-morbidities was 41 years (P < 0.005). Mortality was seen among 81% (13) of patients who were on ventilator support. Added mortality in specific human group demands continuous surveillance monitoring followed by the detection of mutation, even in susceptible animal population.