Associate Professor, Department of Community Medicine Cum Nodal Officer, National Vector Borne Disease Control Program and Integrated Disease Surveillance Project, Sri Guru Ram Das Institute of Medical Sciences and Research, Sri Amritsar
Online published on 26 April, 2016.
Pandemic H1N1/2009 influenza was reported for the first time in Mexico in April 2009. WHO on 11th June 2009 indicated a global pandemic. The first confirmed case of H1N1 in India reported on 16 th May, 2009 was a passenger, travelled from USA to Hyderabad.
Surveillance for H1N1 was done through IDSP in district. The nasopharyngeal swab samples of suspected case-patients were collected and sent to Post Graduate Institute of Medical Sciences and Research, Chandigarh for confirmation.
First case of H1N1 was reported on 3rd October 2009 and out of 136 samples tested 36 were positive. Maximum H1N1 cases were found in year 2010 and no case in year 2011. The mean attack rate of cases remained 0.238/lac population. H1 N1 showed cyclic trends of about 3 to 4 years. CFR in these years remained 36.1%. Maximum number of cases was reported in age 21 to 30 years and minimum > 50 years age. Aattack rates were higher in males and rural populations, with highest peak in December to March.
Mean attack rate observed was lower than in Hyderabad and other parts of India in year 2009. Case fatality rate was higher than in Hyderabad, US and UK. Maximum number of cases reported in age 21 to 30 years and the minimum in age > 50 years, resembled with studies of USA, Canada, UK, Andhra Pradesh and other parts of India. Peak of cases in December to March was different from Andhra where it peaked in August to October in years 2009 and 2010; and in Eastern India, where peak was in June-July in year 2010.
H1N1, pandemic, IDSP, attack rate, CFR and surveillance
