Health Undersecretary Ferruccio Fazio said the country only has enough vaccine to cover 25 percent of the population, far below the target of 75 percent, ANSA reported Thursday.

Fazio said the shortage is most acute for children and people with chronic illnesses.

Italy offers free flu shots for adults over the age of 65, infants, adults with chronic illnesses, pregnant women, hospital patients, doctors and health workers.

Aurelio Sessa of the Italian Medical Society said many doctors, health workers and caregivers fail to get flu shots, putting other people at risk of they get sick.

Sessa said the World Health Organization predicts this year's flu outbreak will be more aggressive than in the past two years, ANSA said.