WARWICK is battling through the worst flu season experienced by local medical professionals.

Even those vaccinated against the flu have been succumbing to the illness, which is emptying classrooms and workplaces across the Rose City.

Condamine Medical Centre's Dr Lynton Hudson said this was the most severe season he had seen, causing particular problems in the elderly, who were at risk of secondary infections.

Dr Hudson warned those who had the flu shot could still be susceptible if they were too vigilant and got as early as March.

"It may only last three months, it means you're only covered to the end of June,” Dr Hudson said.

"We know the bad flu tends to be August, we're trying to get people to have it later.”

Dr Hudson is concerned Warwick could see a second wave of the flu after this week's Ekka, when people typically contract the illness.

"If we get a whole lot of (influenza) B coming through we might get a second round,” he said.

Darling Downs Public Health Unit director Dr Penny Hutchinson said there were 869 influenza notifications in the Darling Downs this year and 75 people had been hospitalised.

Warwick Hospital has seen an influx of flu patients this year.

Dr Hollie Berghofer said this year had brought more confirmed influenza A cases than she had seen in the past two years in Warwick.

She believes the flu season will start to ease off at the start of next month.

Warwick Friendly Society Pharmacy general manager Ahmed Almesfer said flu-specific medication Tamiflu has been running out in stores.

"We're getting plenty of prescriptions from the doctors, we've got orders of the Tamiflu coming in soon,” he said.

"We're running out faster than we can buy them.”

Mr Almesfer said the medication was most effective in the first 48 hours of contracting the flu.

"If patients can't get hold of it early on they can take longer to recover,” he said.

As flu is contracted through droplets in the air, Dr Hudson suggested thorough handwashing and coughing into hands.

It is also not too late for those who haven't been infected to get vaccinated.