New Delhi, Aug. 26 -- Swine flu accounts for 98% of influenza cases tested across the country, according to the Indian Council of Medical Research, which also believes that there is no reason for panic as no deaths have been reported from the H1N1 subtype of the influenza A virus so far. "Our surveillance network has shown about 98% of the cases that are tested are of H1N1; however, there is no need to panic as there is no shift in the seasonal flu pattern that we normally see. There are two peaks usually- monsoon and winters- and the cases that we are seeing are usual for this time of the year. We haven't found any trend or pattern out of the usual that should concern us. Having said that we have to be watchful and follow preventive measures," said Dr Rajiv Bahl, director-general, Indian Council of Medical Research (ICMR). Still, in a country where it is estimated that less than 2% of the population has ever received a flu shot, leave alone an annual one, the flu can spread rapidly given the absence of any kind of herd immunity against a virus with a moderate reproduction number (1.3-2.8 according to previous estimates, though this sometimes varies by outbreaks), which is a measure of how contagious it is. Annual flu shots are the only insurance against seasonal flu outbreaks. To be sure, flu shots are cost-prohibitive , ranging from Rs.2,000 to Rs.4,000, so not everyone can afford it, especially in a country like India. Bahl added that while the number of infections may have risen over the past few weeks, there aren't too many severe cases needing hospitalisation....