Increase in Influenza-like illness
Influenza Season 2007/2008
During week 1 2008 (week ending January 6th), the general practitioner consultation rate for influenza-like illness (ILI) in Ireland increased to 52.4 per 100,000 population from a rate of 16.3 per 100,000 for week 52, 2007. This rate exceeds the threshold at which the UK National Institute of Clinical Excellence (NICE) guidelines (2003) for the use of antiviral drugs is triggered. ILI rates increased in all age groups and are highest in the 15 to 64 year age group. Much of the increase is from cases of influenza A in the 15 to 64 year age group. A small number of influenza B cases have also been reported.
In line with the NICE guidelines, the use of antiviral drugs for the prevention or treatment of influenza in at-risk groups is now recommended.
A summary of the NICE guidance is given below for ease of reference:
Antivirals
Recommendations on the use of antiviral neuraminidase inhibitors for the treatment of influenza when influenza is known to be circulating in the community
Algorithm for the use of antiviral drugs for the prevention (prophylaxis) of influenza
Note: The NICE algorithm on prescribing oseltamivir (Tamiflu) for prophylaxis refers to using oseltamivir (Tamiflu) in persons aged 13 years and older. In January 2006, oseltamivir was licensed for prophylactic use in children aged one year and over. NICE are reviewing their current guidelines at present. In the meantime until NICE completes its review, it would be appropriate to use oseltamivir (Tamiflu) for prophylaxis in persons aged 1 year and over according to the other conditions laid out in the above NICE algorithm for prophylaxis of influenza. Prescribers should also note a concomitant change to the licensed duration of post-exposure prophylaxis in children and adults which is now ten (10) days (as opposed to the previous seven (7) days).
Influenza Vaccine
As influenza-like illness rates are increasing and influenza A and B are circulating, it is also important that persons in at-risk groups for influenza are vaccinated as these groups are at higher risk of developing complications from influenza.
Risk groups for influenza vaccine are outlined below as per the Immunisation Guidelines for Ireland 2002 (Chapter 7)
- All persons aged 65 years or older
- Persons with chronic illness requiring regular medical follow-up such as chronic heart disease, chronic lung disease, chronic renal disease, diabetes mellitus etc.
- Persons who are immunosuppressed due to disease or treatment, including asplenia or splenic dysfunction
- Children and teenagers on long-term aspirin therapy
- Residents of nursing homes, old people's homes and other long stay facilities where rapid spread is likely to follow introduction of infection
- Health care workers and carers of those in at risk groups.
The Immunisation Guidelines for Ireland 2002 are available at:
http://www.ndsc.ie/hpsc/A-Z/VaccinePreventable/Vaccination/Guidance/
Information on NICE guidance
Details of the NICE recommendations on use of antiviral agents for influenza prophylaxis can be found at: http://www.nice.org.uk/nicemedia/pdf/67_Flu_prophylaxis_guidance.pdf and http://www.nice.org.uk/nicemedia/pdf/67_Flu_prophylaxis_A4_summary.pdf
Details of the NICE recommendations on use of antiviral agents for influenza therapy can be found at: http://www.nice.org.uk/nicemedia/pdf/58_Flu_fullguidance.pdf and http://www.nice.org.uk/nicemedia/pdf/58flua4summary.pdf.
Further Information
Details of Influenza Activity in Ireland are available on the HPSC website at: http://www.ndsc.ie/hpsc/A-Z/Respiratory/Influenza/Publications/20072008Season
Details of Influenza Activity in Europe are available on the EISS website at http://www.eiss.org/cgi-files/bulletin_v2.cgi
Details of Influenza Information for Health Professionals on the HPSC website at:
http://www.ndsc.ie/hpsc/A-Z/Respiratory/Influenza/SeasonalInfluenza/Guidance