Antiviral drugs should not be relied upon in H1N1v flu
It is likely, but not proven, that oseltamivir can prevent flu caused by the 2009 H1N1 virus (H1N1v). Clinical evidence of its effectiveness as a cure is fragmentary. Given antivirals' adverse effects and dubious efficacy, as well as diagnostic uncertainties, these drugs should be reserved for patients at high risk of severe complications who have been in close contact with an apparently contagious person with confirmed or very probable H1N1v flu when the epidemic is at its peak.

Pregnant women should avoid H1N1v flu through frequent hand-washing and vaccination
Among women contracting 2009 A/H1N1 flu (H1N1v) during the third term of pregnancy, hospitalisations have been around 4 times more frequent than among the general population. The absolute risk of death seems to be higher than among the general population (which is around 1 death per 20,000 people displaying symptoms). The risk-benefit balance of taking antivirals during pregnancy is uncertain. It is better for pregnant women to reduce the risk of infection through hygiene measures, especially frequent hand-washing, and through vaccination with an H1N1v split virus vaccine with no adjuvants.

The risk to infants is similar to that of seasonal flu Published data do not indicate a higher risk for healthy infants from the 2009 H1N1 (H1N1v) virus than from seasonal flu. Some infants are at high risk of severe complications in the event of flu. They should be vaccinated, preferably with a split virus vaccine with no adjuvants. Antivirals should be restricted to some infants at a high risk of complications when H1N1v flu is proven or highly probable.

For more on the H1N1 flu:
> H1N1v flu vaccines (Celvapan°, Focetria°, Pandemrix°, Panenza°), December 2009
> Flu prevention: first and foremost, wash hands often, December 2009

©Prescrire December 2009

Sources: "Eviter la grippe H1N1v ches les femmes enceintes : lavage de mains et vaccination " Rev Prescrire 2009; 29 (313): 850-851. "Grippe H1N1v chez les nourrissons: similaire à la grippe saisonnière" Rev Prescrire 2009; 29 (313): 851-852. "Grippe H1N1v : ne pas trop compter sur les antiviraux" Rev Prescrire 2009; 29 (313): 849-850.