28/11/2022
INFLUENZA AND RESPIRATORY VIRUS TREATMENTS UPDATE HSE WINTER 2022:
Dear colleagues,
I would be grateful if you would bring this notice to the attention of all relevant staff in your organisation, general practice, department, hospital, and other healthcare settings.
During week 46 2022 (week ending November 20th, 2022), influenza surveillance indicators have increased in Ireland. In light of this increase in influenza activity, people presenting with influenza-like illness (ILI) are likely to be infected with the influenza virus. In this context, it is recommended that antivirals be used for the treatment and prophylaxis of influenza in clinical at-risk groups as well as any persons who are at risk of severe illness and/or complications from influenza including those who are resident in congregate settings such as care homes. The Guidance on the use of antiviral agents for the treatment and prophylaxis of influenza is available on the HPSC website.
Summary of influenza activity in Ireland
Up to the week ending November 20th, 2022 (week 46 2022), the most recent influenza surveillance data indicate that the number of confirmed influenza cases notified to the HPSC via the National Computerised Infectious Diseases Reporting system increased. One hundred and ninety-two laboratory-confirmed influenza cases were notified to the HPSC during week 46 2022, compared to 170 cases notified in week 45 2022. The median age of the 192 notified influenza cases in week 46 was 31 years (interquartile range: 13-59 years). Of the 192 cases, 68 (35%) were reported as hospital inpatients with a median age of 35 years (interquartile range: 7-71 years). The overall influenza positivity reported from the National Virus Reference Laboratory was 3.7% (15/409) during weeks 45 and 46 2022.
In addition, the sentinel GP influenza-like illness (ILI) consultation rate was above the baseline threshold (18.0/100,000) during week 46 at 22.5/100,000 population and week 45 at 21/100,000 population.
Since the beginning of October 2022 (2022/2023 flu season to date), 828 laboratory-confirmed influenza cases have been notified to HPSC, with 298 (36%) of these cases reported as hospital inpatients, including 11 confirmed influenza cases admitted to critical care units. Detections of influenza A(H3), A(H1)pdm09, and B have been notified to HPSC this season. To date, this season, four deaths in notified influenza cases have been notified to HPSC. Nine outbreaks of confirmed influenza A, four in acute hospitals, three in nursing homes, and two in a residential institution have been notified to HPSC.
Given the increases observed in most influenza surveillance indicators over the last week, HPSC considers that influenza viruses are currently circulating in the community in Ireland.
The latest influenza surveillance report published each Thursday is available here on the HPSC website.
Update on antiviral guidance
Antiviral Guidance-Ireland
Due to the levels of influenza activity reported last week (week ending November 20th, 2022) in Ireland, antiviral drugs for the treatment and prophylaxis of influenza in at-risk patients are recommended in line with the Guidance on the use of antiviral agents for the treatment and prophylaxis of influenza which is available on the HPSC website. Those in clinical at-risk groups presenting with symptoms of influenza and those with clinical complications from influenza or progressive influenza illness including any hospitalised cases should be considered for treatment with antivirals.
Additional resources for clinicians on the use of antivirals are available at:
HSE:
https://www.hse.ie/eng/services/list/2/gp/antibiotic-prescribing/conditions-and-treatments/influenza/seasonal-influenza.html
European Centre for Disease Prevention and Control (ECDC):
https://ecdc.europa.eu/sites/portal/files/documents/Scientific-advice-neuraminidase-inhibitors-2017.pdf and https://ecdc.europa.eu/en/seasonal-influenza/prevention-and-control/antivirals
Public Health England:
https://www.gov.uk/government/publications/influenza-treatment-and-prophylaxis-using-anti-viral-agents
CDC in the USA:
http://www.cdc.gov/flu/professionals/antivirals/summary-clinicians.htm
The defined risk groups for complicated influenza requiring antiviral treatment and chemoprophylaxis are:
· Those aged 65 years and older
· Pregnant women (including up to two weeks post-partum)
· Children aged
Seasonal Influenza
