Flu outbreak hits babies, tots hardest

Vaccination doses had reached one million since 2009. Photo / Thinkstock

109 admitted to Auckland hospitals — double the previous year, report finds.

Hospital admissions for the flu and respiratory illness more than doubled this year compared with last year - with babies and toddlers among the worst affected, a new study says.

Results from the third year of a five-year multimillion-dollar study also showed this year's flu season claimed four lives. There were no deaths last year.

The Southern Hemisphere Influenza and Vaccine Effectiveness Research and Surveillance (Shivers) study has been tracking patients admitted to Auckland District Health Board and Counties Manukau District Health Board hospitals with severe acute respiratory illness and those who went to their GP with flu symptoms.

Principal investigator Sue Huang said there were 109 patients admitted to the hospitals' intensive care units with influenza and respiratory illness this year, compared with 52 last year.

The study's co-lead investigator, Associate Professor Nikki Turner from Auckland University, said there wasn't any particular reason for the dramatic jump in numbers this year.

"Last year was a relatively quiet flu year. It's not that we're doing anything differently, but some years you have more community immunity."

Babies (under 1 year old) were hardest hit with the highest influenza hospitalisation rate - almost five times higher than children aged 1-4 years, the second-hardest hit age group, the study found.

Last year, patients aged 5-19 years had the highest rate.

The other group with high illness rates were those living in crowded and draughty housing conditions.

Dr Huang said the influenza vaccine was the main weapon to fight the virus. The predominant strain of flu to hit the population this year was the H1N1 strain, which the vaccine protected against.

Vaccination doses had reached one million since 2009, but even more needed to take up the jab in order for hospital admission figures to decrease, she said.

The vaccine was free for anyone aged over 65, anyone who suffered from specific medical conditions, and pregnant women.

Having the vaccine free for all would be "lovely", but there were factors to consider such as the cost, she said. People in high-risk groups needed to think about vaccination for next year.