The number of people sickened by swine influenza in the United States increased to 642 today, and the virus was likely to spread all over the country, dpa quoted the Centres for Disease Control and Prevention (CDC) as saying. The Atlanta, Georgia-based centre said there were confirmed cases in 41 states, with an additional 850 probable cases. The rapid increase in the number of cases was attributed both to better testing as well as the steady spread of the virus that epidemiologists are still struggling to understand. Those infected were in the age range of 3 months to 81 years with a median age of 16 years. An estimated 58 per cent of the confirmed illnesses were in the under-18-years group. So far 2 deaths have been reported in Texas and 35 people have been hospitalized in 14 states, the CDC said. The fatalities include a 23-month-old boy from Mexico City who died in a Houston hospital and a pregnant woman in her 30s. "It's important that people have respect for (flu) virus because each year it does cause severe illness and death in this country," said CDC acting director Richard Besser. At least 36,000 people die every year from seasonal flu in the US alone. Besser said there remained cause for concern and heightened vigilance as the swine flu virus was expected to spread to all the US states and cause more illnesses, hospitalizations and deaths. The CDC has sent testing kits around the US as well as to 16 other countries to help with diagnostic capabilities. Without providing further details, Besser said the CDC was also investigating health care worker transmission in Texas and California, which have reported 61 and 67 cases each. Illinois reported 122 cases, New York 97, Arizona 48, Massachusetts 45 and Delaware 33. In Geneva, the World Health Organization said a technical committee would next week recommend steps to be taken regarding the production and purchasing of vaccines. The US government was considering a vaccination campaign in the fall that would involve three flu shots - one for seasonal flu and two others to combat the new A(H1N1) strain. But the CDC said it was too early to determine when the vaccine would be available and how many doses would be required. Besser said a series of studies would first need to be conducted to determine how much of the antigen needs to be in the vaccine to stimulate protection for an individual. The current WHO pandemic alert level stands at phase 5, one below the highest, which means that there is no evidence so far of sustained human-to-human transmission at the community level outside of North America. "At the rate the virus is spreading in other countries, I would be surprised that we don't get to a level 6," Besser said.
