Reserve Antivirals for Severe H1N1 Influenza and Prevention of Complications

Reserve antivirals for adults and children over age 1 who have severe novel H1N1 influenza or who are at high risk for complications. The World Health Organization (WHO) emphasized its existing recommendations in light of a recent meta-analysis published in BMJ that found the neuraminidase inhibitors oseltamivir and zanamivir provide only a “small benefit” in children with mild seasonal influenza.

Pregnant women are among the patients who should receive antivirals. Those infected with 2009 novel H1N1 virus had a higher rate of hospitalization and greater risk of death than the general population, according to a study recently published in Lancet.

“Clinicians who treat pregnant women should have a system in place for triaging pregnant women with influenza-like symptoms and they should not delay in initiating appropriate antiviral therapy,” said Dr Denise Jamieson of the CDC and lead author of the Lancet study. “Some clinicians hesitate treating pregnant women with antiviral medications because of concerns for the developing fetus, but this is the wrong approach. It is critical that pregnant women, in particular, be treated promptly.”

Six deaths of pregnant women with novel H1N1 influenza were reported to CDC between April 15 and June 16, 2009, representing 13% of the total 45 deaths reported to CDC during that period. The women had all been previously healthy, and they all subsequently developed primary viral pneumonia that led to acute respiratory distress requiring mechanical ventilation. All of the pregnant women who died had not received antivirals early enough to be of benefit.