Experts are warning the flu season is not over.

In fact, the concept of a flu season is becoming a misnomer as influenza cases spike year-round.

The horror winter, which saw more than 65,000 confirmed cases, is being blamed for the Royal Children’s Hospital running $20 million over budget.

The hospital’s associate professor, Nigel Crawford, says the virus is still out there, midway through spring.

“We actually don’t see the flu disappear as much as we used to — even over January and February we still see flu cases,” he told Ross and John.

“This year in April and May we saw a high number of cases.”

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