One case of influenza A was detected in this country during the summer, the first influenza surveillance report for the current 2021/22 season shows.
Notified in July, it was confirmed as an imported travel case.
Throughout the last influenza 2020/2021 season, no detected influenza cases acquired in Ireland were reported.
Influenza activity peaked in late December 2019 and decreased significantly in the early months of 2020.
As a result of the pandemic, published Health Protection Surveillance Centre (HPSC) surveillance reports began to show a fall off in confirmed cases of influenza, which has continued.
Although described as “moderate”, the previous 2018/2019 influenza season had a significant impact on the Irish health system, with high numbers of influenza detections and high hospitalisation and ICU admission rates. In recent weeks, influenza detections globally had increased although at levels lower than expected for this time of the year.
In Europe, the HPSC report added, influenza activity was at low levels, with both influenza A and B detections reported, predominantly influenza A(H3N2).
Circulation of influenza viruses across Europe was anticipated in the coming weeks/months. Of 41 sentinel GP influenza-like illness and 147 non-sentinel respiratory specimens tested and reported by the National Virus Reference Laboratory (NVRL) during the week 4 to 10 October, all were negative for influenza.
The first surveillance report for the 2021/22 season noted that the influenza-like illness (ILI) rate had been below the baseline threshold (18.1 per 100,000 population) for the past five weeks and there was no evidence of influenza circulating in the community.
As a result, the HPSC stated the weekly flu report would be issued on a fortnightly basis for the coming weeks.
Aside from influenza, however, latest reports from the HPSC found respiratory syncytial virus (RSV) activity in Ireland was at higher levels than usually observed at this time of year.
Rhinovirus/enterovirus positive detections (non-sentinel sources) had increased in September/October 2021, with positivity at 32.7 per cent (48/147) during week 4 to 10 October. Parainfluenza 3 viruses and other respiratory viruses (ORVs) were being detected at lower levels.