Flu epidemic level breached for first time since beginning of COVID-19 pandemic over Christmas
Flu activity rose over Christmas and breached the threshold for an epidemic for the first time this winter, according to the latest bulletin from the Public Health Agency (PHA).
The PHA also confirmed there were eight outbreaks of flu and flu-like illnesses (FLI) in hospitals and care homes between Boxing Day and New Year’s Day, bringing to 21 the total number of outbreaks this winter so far.
The rate of GP consultations for flu in week 52 (December 26-January 1) was 14 per 100,000 of population. This was slightly lower than for week 51 (December 19-25) when the rate was 17.8 per 100,000. Figures for both weeks were released by the PHA on Thursday, January 5.
The latest figures show we are now officially in a flu epidemic, albeit still one of low intensity. It is the first time the epidemic threshold has been breached since the beginning of the COVID-19 pandemic.
The flu activity rate is calculated using the Moving Epidemic Method (MEM), which is based on the last ten flu seasons.
Once the baseline has been breached the following steps are escalated as necessary: low activity (11.3 to 21.8 consultations per 100,000); moderate activity (21.8 to 57); high activity (57 to 87.1); and very high activity (over 87.1 consultations).
The latest flu bulletin states: “Flu/FLI consultation rates were highest in 45-64 year olds in week 52 at 19.7 per 100,000 population. Rates are higher in all age groups when compared to the same period in 2021/22.”
The rate of flu consultations at Primary Care Out-of-Hours (OOH) Centres also rose over Christmas.
“The Flu/FLI consultation rate in Primary Care OOH Centres was 16.3 per 100,000 population in week 52. This is higher than week 51 (5.2 per 100,000) and higher than the same period in 2021/22 (5.8 per 100,000),” the bulletin stated.
The PHA confirmed there were eight viral outbreaks in care homes between Boxing Day and New Year’s Day.
"There were eight respiratory outbreaks reported to the PHA Health Protection acute response duty room during week 52. These were all outbreaks of Flu A (untyped), all of which were reported in a care home setting.
"To date, in 2022/23, there have been a total of 21 confirmed influenza outbreaks reported (11 in a care home setting, one in a supported living facility and nine in a hospital) and one respiratory syncytial virus (RSV) outbreak (care home setting),” it stated.
There was a rise in respiratory deaths year-on-year.
"In week 52, 78 respiratory associated deaths out of 238 all-cause deaths were reported (33 per cent). This is higher than the same period in 2021/22 (54 respiratory deaths out of 243 all-cause deaths, 22 per cent),” the bulletin revealed.
The deaths included those where bronchiolitis, bronchitis, influenza or pneumonia were mentioned on the death certificate.
The bulletin shows H1N1 - the virus identified in Mexico which was known as ‘swine flu’ during the 2009 global pandemic – is the dominant strain in circulation this season. H1N1 is now a seasonal flu strain.
In week 52, 167 hospital samples were positive for H1N1.
Sixty-two hospital samples were positive for Flu A (H3); 48 samples were positive for Flu A (untyped); and five samples were positive for Flu B.