Historically, pregnant women have had higher rates of complications when infected with novel or seasonal influenza strains, and emerging data suggest the H1N1 strain is no exception. In a recent publication, scientists noted that pregnant women have been admitted to the hospital with H1N1 infections at a much higher rate than in the general population,0.32per100 000vs0.076per 100 000 (Jamieson DJ et al. Lancet. 2009; 374[9688]:451-458). Between April 15 and May 18, there were 34 confirmed cases of H1N1 influenza in pregnant women in the United States, and about one-third of these individuals were admitted to a hospital; between April 15 and June 16, of the 45 deaths of US individuals attributed to the virus, 6 were among pregnant women. Yet despite the risks influenza pose during pregnancy, pregnant women often do not receive antiviral drugs or seasonal influenza vaccination. Only half of US pregnant women with confirmed cases had received oseltamivir, which is recommended by the CDC. Also, only about 15% of pregnant women are vaccinated for seasonal influenza, Schuchat noted. “It’s vital for pregnant women who have respiratory illness and fever to get early treatment, and we think antiviral medications for them can be life saving,” Schuchat said. Young adults are another group of particular concern. Older adults, who may have some immunity from exposure to a similar virus in the 1940s and 1950s, have been largely spared from infection with the currently circulating H1N1 virus. Morse noted that only 1% of confirmed cases have occurred in individuals aged 65 years or older and that the age group of 50to 64-yearolds has also experienced very few infections. Schuchat emphasized that older individuals should still receive the seasonal influenza vaccine. Living situations and social behaviors of college-aged individuals aged 19 to 24 years may place them at greater risk of infection, Schaffner noted. “We anticipate this virus, when it gets started this fall, will have a substantial impact on this population,” he said. In fact, the flu season may begin earlier than usual this year if H1N1 cases spikewhenchildrenandcollegestudents return to schools, said Schaffner. He explained that the H1N1 virus has continuedtocauseoutbreaksatsummercamps and summer college sessions. “We may have a double-barreled flu season: first H1N1, then seasonal influenza,” Schaffner said. In anticipation of these increased demands, he recommended thatphysiciansbeginproviding theirpatientswiththeseasonal influenza vaccine as soon as it becomes available in late August or early September.