Researchers in Toronto have issued a warning that even mild asthma in a child increases its risk of hospitalization due to a severe H1N1 flu infection.

Reviewing the charts of 58-children admitted to hospital with pandemic H1N1 between 8th May and 22nd July, doctors at the Hospital for Sick Children then compared them with 200-others who had been hospitalized with seasonal flu in the past 5-flu seasons.

The findings showed children admitted with H1N1 were more likely to have asthma than those hospitalized with seasonal influenza (22% versus 6%), with overall 46 or 79% hospitalized with H1N1 having underlying medical conditions, such as, asthma, chronic lung disease or heart disease.

However, there were no deaths among the children hospitalized with H1N1, compared to one death among those hospitalized with regular flu.

The study though small stresses the importance of getting children vaccinated to prevent them from falling victim to the H1N1 virus. World Health Organization officials have already confirmed the H1N1 vaccines to be as safe as seasonal flu shots.

Side-effects to the H1N1 vaccine, include reactions such as pain at the injection site, swelling, redness and other reactions like fever, headache, muscle pain or fatigue, which are generally resolved within a day or two, as well as, a variety of allergic reactions.