HSE give briefing on Irish flu virus rates

THE HSE has provided a national update on the flu virus hitting the country.

Dr. Kevin Kelleher, HSE Assistant National Director of Public Health said, “Influenza activity has increased in the past week and will probably peak in the next week or two.

“The ILI (influenza like illnesses) rate for the week ending January 8 increased to 95.3 per 100,000. This ILI rate is high, however not as high as those reached during the 2000/2001 (A(H1N1) pdm09) and 2008/2009 (A(H3N2)) influenza seasons and it is not possible to say at present if these higher levels will be reached this season.

“It is expected that ILI rates will remain above the baseline threshold until mid-February and influenza activity will continue for some weeks after the ILI rates go below baseline and this may be evidenced by continuing outbreaks in RCFs.

In this context, it is important that older people, their carers and Health Care Workers (HCWs) receive the influenza vaccine if they have not already done so. It is also important that antiviral medications are used for the treatment of influenza in all at-risk groups and in particular in the older age groups. Antivirals have been shown to reduce the duration of symptoms and to protect against hospitalisation due to influenza and death from influenza”.

The dominant virus currently in circulation is influenza A(H3N2). However it is possible that later in the season, influenza B will circulate. In addition, norovirus continues to circulate and also impacts on the elderly in terms of morbidity (outbreaks in RCFs and acute hospitals).

Dr. Joan O’Donnell, specialist in Public Health, said, “There are 15 reported deaths due to influenza to date, the majority in those aged 65 years and older. However, in those aged 65 years and older, infection with influenza can exacerbate other underlying illnesses e.g. COPD and CHF and this may result in death. These flu-related deaths account for 500 excess deaths per annum in this age group on average. The excess death figures will be available later in the season.

“The Irish sentinel GP practices cover 5-6% of the national population which is higher than most European countries. The sentinel GPs undertake clinical and virological surveillance of influenza. This system is complemented by the GP OOH surveillance system which reports on all influenza-related calls to GP OOH services. Both of these systems complement each other and outputs in general mirror each other.”

The ILI rates increased to 95.3 per 100,000 week ending January 8 and are above the threshold for medium activity (58.9/100,000).

To date this season, 535 hospitalised influenza cases, 27 ICU flu cases and 63 ILI/influenza outbreaks (57 in RCF and 6 in acute hospitals) have been reported to the Health Protection Surveillance Centre (HPSC). Those aged 65 years and older are the group most affected. 13 of the 15 deaths occurred in those aged 65 years and older and no flu-related deaths in children have been reported to date.

Updated influenza vaccination rates in those aged 65 years and older will not be available for at least two weeks. The influenza vaccine is 40-60% effective but in older people, this drops to ≤40%, hence the need for carers and HCWs to receive the vaccine in order to provide a protective ring around this vulnerable group.

Uptake in influenza vaccine in HCWs is improving with doctors/dentists showing greatest improvement and nurses being the least improved. Some hospitals have shown influenza vaccination coverage of ≥60% this season which is encouraging.