Increase in influenza-like-illness rate raising Covid-19 concerns

The sentinel GP influenza-like illness (ILI) consultation rate has increased, raising concern about the continued spread of Covid-19 in the community, according to the latest data from the Health Protection Surveillance Centre (HPSC).  

The data shows the ILI rate had been falling, but increased from 18 per 100,000 population in week 17 to 21.9 per 100,000 population in week 18 (ending 3 May).

This is significant as, according to the HPSC, the elevated rate is reflective of the Covid-19 pandemic, rather than influenza activity.

The national public health emergency team (NPHET) uses a number of barometers to measure the prevalence of Covid-19 in the community and associated risks.

However, the best barometer, according to GP Dr Ray Wally, former IMO President, is the ILI rate, which is published weekly by the HPSC. 

Based on this barometer only, and there are other barometers, such as the number of Covid-19 cases in ICU for instance, Dr Walley said this evidence shows the virus has not gone away.

“The figures reflect continued community prevalence,” Dr Walley told the Medical Independent.

“The figure is an increase but in the scheme of things it more reflects that the virus is still there rather than it has gone away or greatly increased.

“The rate is only one figure that the State needs to take into account when easing restrictions. The figure from week 19 due this will be of great interest.”

Given that restrictions are due to ease shortly, it is concerning that this figure has increased. 

All ILI patients are currently referred for Covid-19 testing.

According to the ‘Influenza Surveillance in Ireland – Weekly Report Influenza Week 18 2020 (27 April – 03 May 2020)’, the elevated rate in recent weeks is “reflective of the current Covid-19 pandemic rather than influenza activity”.

Testing for influenza has been “reduced significantly due to the need to allocate resources to the Covid-19 pandemic response,” the report adds.

During week 18, 88 per cent of the 60 sentinel GP practices reported data. The ILI rate was highest in those aged over 65 years and lowest in those aged between 5-14 years and 0-4 years.