A test for our readers

If you have some free time, consider volunteering for a national study that will compare a new smallpox vaccine, Imvamune, with the existing treatment, Dryvax. (Volunteers need to be healthy, at least 18 years of age and born after 1971.) “Vaccines prevent disease by giving the body a jump-start at recognizing the infecting virus or bacteria,” says Dr. Sharon Frey of Saint Louis University, which is leading the nationwide project. On this point, the two vaccines are similar; both rely on the live vaccinia virus. But Imvamune’s is “highly attenuated” and is said to have fewer side effects than Dryvax. The study is sponsored by the National Institutes of Health in cooperation with Bavarian Nordic A/S, Imvamune’s manufacturer, and 215 people are expected to participate. No details were provided as to what exactly the volunteers will be subjected to.