Increase in Influenza-like illness
During week 5 2007 (week ending February 4th), the general practitioner consultation rate for influenza-like illness (ILI) in Ireland increased to 44.5 per 100,000 population from a rate of 22.5 per 100,000 for week 4. 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. Much of the increase is from cases of influenza A (H3, H1 and unsubtyped) in the 15 to 64 year age group and in 0 to 4 year olds.
In line with the NICE guidelines, the use of antiviral drugs for the prevention or treatment of influenza is now recommended. A summary of the NICE guidance is given below:
Recommendations on the use of antiviral neuraminidase inhibitors for the treatment of influenza when influenza is known to be circulating in the community may be found here
Algorithm for the use of antiviral drugs for the prevention (prophylaxis) of influenza may be found here
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. 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 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).
As influenza like illness rates are increasing and influenza A is 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
• In addition to these groups, vaccination should also be considered for health care workers both for their own protection, as these are a group likely to come into contact with influenza during outbreaks, and for the protection of their patients.
The Immunisation Guidelines for Ireland 2002 are available at http://www.ndsc.ie/hpsc/A-Z/VaccinePreventable/Vaccination/Publications/ImmunisationGuidelines/