Flu activity has decreased over the last week, however at-risk groups are still being urged to get vaccinated if they have not already done so.

According to the Health Protection Surveillance Centre (HPSC), influenza-like illness (ILI) activity was at low levels during the third week of January. However, flu viruses are expected to continue to circulate for at least the next three to four weeks.

ILI rates decreased to 30 per 100,000 population during the week ending January 19. The week before, they were at 65 per 100,000.

The number of hospitalisations also fell from 609 during the second week of January, to 351 during the third week. The highest hospitalisation rates continue to be recorded among people over the age of 65 and children under the age of five.

To date, there have been almost 3,100 hospitalisations as a result of flu, with 103 of these being admitted to critical care units. Fifty-two people have died as a result of flu, with most of these deaths in the over-65 age group.

The HPSC is urging people in at-risk groups to still get vaccinated against influenza if they have not already done so, as it is still circulating in the community.

People in at-risk groups include those over the age of 65, pregnant women and those with long-term chronic illnesses, such as heart disease and diabetes.

The flu vaccine is available free of charge from GPs for all people in at-risk groups, and from pharmacists for everyone in at-risk groups aged 10 years and older. An administration charge may apply to people who do not hold medical cards or GP visit cards

"Vaccination remains the most effective means of preventing infection by seasonal influenza viruses and can reduce severe disease that can lead to hospitalisation and death. The vaccine takes two weeks to take effect once received," the HPSC said.

Those who contract flu are advised to stay at home, rest, drink plenty of fluids and use over-the-counter remedies like paracetamol to ease symptoms. More advice is available here.