Readers may also be interested in the World Health Organisation briefing note on the use of anti-virals during the current pandemic, which do not support the routine use of anti-virals in either children or adults experiencing mild symptoms of H1N1 infection.

Adults:

For patients who initially present with severe illness or whose condition begins to deteriorate, WHO recommends treatment with oseltamivir as soon as possible. Studies show that early treatment, preferably within 48 hours after symptom onset, is strongly associated with better clinical outcome. For patients with severe or deteriorating illness, treatment should be provided even if started later. Where oseltamivir is unavailable or cannot be used for any reason, zanamivir may be given.

This recommendation applies to all patient groups, including pregnant women, and all age groups, including young children and infants.

For patients with underlying medical conditions that increase the risk of more severe disease, WHO recommends treatment with either oseltamivir or zanamivir. These patients should also receive treatment as soon as possible after symptom onset, without waiting for the results of laboratory tests.

As pregnant women are included among groups at increased risk, WHO recommends that pregnant women receive antiviral treatment as soon as possible after symptom onset.

Children:

WHO recommends prompt antiviral treatment for children with severe or deteriorating illness, and those at risk of more severe or complicated illness. This recommendation includes all children under the age of five years, as this age group is at increased risk of more severe illness.

Otherwise healthy children, older than 5 years, need not be given antiviral treatment unless their illness persists or worsens.

Remember, adverse effects suspected to be related to anti-virals (oseltamivir or zanamivir) used to treat H1N1 influenza should be reported at the MHRA’s Swine Flu portal: http://swineflu.mhra.gov.uk.