The death toll of the A/H1N1 flu in Canada rose to 55 on Thursday, the Public Health Agency of Canada announced.

That was five more than the number released on Tuesday.

Deaths have now occurred in seven provinces or territories. The French-speaking Quebec has the most deaths at 19, followed by Ontario province at 18.

The total confirmed cases of the H1N1 flu in the country have now surpassed 10,000.

Health authorities are now studying the severe cases of the flu by examining the risk factors for severe infection, including age, weight, gender, underlying diseases, genetic background, and immunization history. Experts will probe the reasons why some people become severely ill very quickly, and seek to determine how long a seriously ill person is infectious.

The lessons learned from this study will help health workers to prepare for the anticipated wave of pandemic H1N1 in the fall, Health Minister Leona Aglukkaq said at a press conference in Ottawa Thursday.

(Xinhua News Agency July 24, 2009)