05.10.2009
Antiviral use and the risk of drug resistance
Pandemic (H1N1) 2009 briefing note
25 SEPTEMBER 2009 | GENEVA -- Growing international experience in the treatment of pandemic H1N1 virus infections underscores the importance of early treatment with the antiviral drugs, oseltamivir or zanamivir. Early treatment is especially important for patients who are at increased risk of developing complications, those who present with severe illness or those with worsening signs and symptoms.[1]
The experience of clinicians, including those who have treated severe cases of pandemic influenza, and national authorities suggests that prompt administration of these drugs following symptom onset reduces the risk of complications and can also improve clinical outcome in patients with severe disease.
WHO encourages clinicians to be alert to two situations that carry a high risk for the emergence of viruses resistant to oseltamivir.
The occurrence of oseltamivir-resistant viruses is expected and is consistent with observations from early clinical trials. As use of antiviral drugs continues to grow, further reports of drug-resistance viruses are certain to occur. WHO and its network of collaborating laboratories are closely monitoring the situation and will issue information and advice on a regular basis as indicated.
Source: who.int
