Flu season could start within weeks, and though early indicators suggest it could be relatively mild this year, health officials are renewing calls for vaccination following one of the deadliest seasons in recent memory.

Last year’s flu season began in late October, peaked in February and didn’t fully cool until May, breaking national records for hospitalization rates along the way.

There’s reason for optimism that this year’s season won’t be as bad.

Globally, the flu season starts in Australia. Its impact there can predict how bad it will be here and how well the annual flu vaccine works against the most prevalent strains.

Last year, Australia’s flu season was nasty.

This year, things have been much more mild, Down Under, according to a report released recently by AARP that quoted national and international health experts.

“It’s quite a contrast from last year, when we had a very severe flu season, with H3N2 predominating,” Kanta Subbarao, director of the World Health Organization Collaborating Center for Reference and Research on Influenza, said in the report.

Health officials still say vaccination is key.

The Australia season is an imperfect predictor because the flu virus can shift and mutate, said Kerri Tesreau with the Missouri Department of Health and Senior Services.

“It does appear the flu season has been mild in Australia and the predominant strain has been H1N1 and the flu shot works well against that,” said Tesreau, the director of the department’s Division of Community & Public Health. “But flu is unpredictable.”

Even if the shot doesn’t completely prevent infection, there’s evidence that it makes the sickness less severe and prevents the kind of cases that caused so much misery last year.

Federal researchers said a record-high 180 children died last year from the flu.