The winter flu season has started and will probably peak in the next three to six weeks, according to the Health Service Executive.
The Director of the HSE's Health Protection Surveillance Service, Dr Kevin Kelleher encouraged people to get vaccinated, particularly those over 65, pregnant women and those under 65 with various health conditions.
Speaking on RTÉ's News At One, he said the vaccine has a very safe record.
The more people who get it, he said, the less likely there will be a serious flu problem in the country.
The flu virus indirectly resulted in the death of 1,000 people in Ireland last season, according to Mr Kelleher.
He said: "Over 1,000 extra deaths happened last winter as a result of the flu, not directly but indirectly.
"We have very good systems with our colleagues in Europe that show this, and last season we had a very major excess number of deaths as a result of the flu, around 1,000."
Minister for Health Simon Harris said: "I would appeal to everyone to follow the HSE's advice over the coming days and weeks on how to recognise the symptoms of flu, what to do if flu is suspected and on how to prevent it spreading between people.
"I'd also like to remind people that it is not too late to get the flu vaccine."