THE number of flu cases in Tasmania increased sharply late last month with two thirds the total reported cases for winter so far notified in the fortnight ending July 29.
Health and Human Services' latest FluTAS report revealed that 387 notifications were received in the last two weeks of July taking the annual total so far to 560.
But the true level of influenza in the community was likely to be much higher.
``Notifications of influenza are only those people who are tested and then test positive,'' the report said.
The most common flu strain in Tasmania this year has been A H3N2 but there have also been reports of high levels of a flu-like illness in the state known as ILI.
Most flu cases have occurred in Southern Tasmania with 449 of the 560 from that region with only 59 in the North and 52 in the North-West.
Influenza A HINI (or swine flu) remained rare, the report said.
It did not specify the number of cases recorded.
The number of weekly flu tests continued to rise in the last part of July with nearly half of the tests being positive for influenza.
But the incidence is expected to fall in August as the peak flu season passes.
Before the increase last month the most common non-influenza respiratory complaints detected were Rhinovirus and Respiratory Syncytial Virus or RSV.
The latest FluTAS report found that the last two weeks in July saw a peak then a decline in the number of Tasmanians reporting fever and cough.
Fever and cough were more common in people unvaccinated for flu.