New threshold for antivirals will increase GP influenza workload
GPs will have to prescribe antiviral drugs more often if plans to lower the thresholds for identifying when flu is circulating in the community are given the go-ahead.
Under the new proposals to be considered by the Department of Health the number of weeks when GPs are advised to consider using antivirals could increase considerably.
Scientists from the Health Protection Agency have recommended lowering the baseline for seasonal activity of flu because fewer people are consulting their GPs when they are ill, making current measures inappropriate.
Under the proposals, the current baseline of 50 consultations per 100,000 – the curent 'trigger' for prescribing antivirals according to NICE guidelines – should be reduced to 30 per 100,000.
The threshold for defining a flu epidemic will be halved from 400 to 200 consultations per 100,000.
In the 2001/2 and 2002/3 seasons, consultations for flu-like illness did not cross the 50 per 100,000 threshold.
Since 1988, the UK has only had one flu epidemic – in 1990 – but under the new thresholds there would have been epidemics in five seasons.
Dr John Watson, head of respiratory diseases at the Health Protection Agency said the HPA was recommending the changes after consultation with the RCGP.
'Data from the RCGP Research Unit indicates there has been a decline in consultation rates for influenza-like illness over a number of years,' said Dr Watson.
RCGP prescribing spokes-man Dr Jim Kennedy, a GP in Hayes, Middlesex, said the lower threshold might increase GP workload and that prescribing antivirals for 'borderline breaches' of flu thresholds did not make sense.
'The population is resistant to average flu,' he said. 'We're overdue a significant antigenic change and if that happens there is a huge workload implication.'
Guidelines recommend prescribing oseltamivir (Tamiflu) within 48 hours of exposure and zanamivir (Relenza) within 48 hours of symptoms, which GPs say is unworkable.
By Emma Wilkinson