Flu on the rise Monday, 6 July 2015

The flu season is under way and the public has been warned - it could be a nasty one.

The latest flu report showed there were 75 flu cases identified in the last week of June, marking a steady two-week rise as the weather cooled.

By far the highest number of cases reported was in the Bay of Plenty, followed by the Wairarapa and Hawke's Bay. All three areas, and the central North Island Lakes district, had a higher than average number of reported flu cases.

Sue Huang, virologist at the Institute of Environmental Science and Research (ESR), said the country had entered the flu season, although how bad it would get was difficult to predict.

Flu cases had been tracking at slightly fewer than last year, but that could quickly change.

"We can never predict precisely but it's seems to be a normal season and it's moving upwards."

One big, and potentially dangerous, change was the strains floating around this year. Last winter A(H1N1) - the strain labelled "swine flu" in 2009 - was the main player in New Zealand. 

However, early signs indicated that this year's more prevalent strain was  A(H3N2), a strain that had already been blamed for a particularly deadly flu season in the northern hemisphere.

Huang said the strain was more likely to cause severe illness than swine flu, particularly among the elderly, the sick and in young children.

"It is a nastier strain. Vulnerable groups tend to suffer more, and end up needing hospital care."

The good news was that, unlike in the northern hemisphere, flu vaccinations in New Zealand underwent some last-minute changes to provide resistance against H3N2.

For the vulnerable groups it was particularly important to get a vaccination, Huang said.

Wellington doctor Nikki Turner, who is also director of the Immunisation Advisory Centre, said she had seen a definite upswing in flu patients coming into the office.

"In the last two weeks we've started to see flu illness rather that just respiratory illness."

Some of her Wellington medical colleagues had seen flu patients who were so sick that they had been sent straight to hospital.

Turner said nearly 1.2 million had now had their flu jabs but many people, even health workers, seemed to still believe they were immune. But not getting immunised put them and other more vulnerable people at risk.

"People just don't think they are going to get it, but it's not just about them."

While there had been a spike in cases, it was still too early to predict whether it would be a severe, or benign, flu season. "Only God has a feel for the season at this time of year."

People who have come down with flu should regularly wash their hands, keep their "social distance" from others, and avoid turning up to the doctor's spluttering all over other patients.

Flu jabs would still be still free until the end of July for people who were over 65, pregnant, or had a long-term health condition.