The Centers for Disease Control and Prevention recommends annual flu vaccination for people 6 months and older. Justin Sullivan/Getty Images hide caption
Maybe she goes to school in Wyoming, where no schools start after 8:30 a.m. iStockphoto hide caption
Ioanna Mattke holds Raven, one of six hens that her family owns. The Mattkes have raised Raven since she was a day old. Jason Beaubien/NPR hide caption
Dugway Proving Ground military base, seen here in 2010, was the source of several anthrax shipments that are suspected of containing live samples of the disease. Jim Urquhart/AP hide caption
Stacy Emminger holds the death certificate for her son, Anthony, who was addicted to heroin. His death was marked as a multidrug toxicity in Pennsylvania. Ben Allen/WITF hide caption
Secretary of State John Kerry and African Union Commission Chairperson Nkosazana Dlamini Zuma signed an agreement Monday to establish the first Centers for Disease Control and Prevention in Africa. The U.S. will provide technical advice and a few staff for the agency. Alex Wong/Getty Images hide caption
Truvada can dramatically reduce the risk of HIV infection when taken as a preventative medicine — if taken every day. Studies are underway to determine if young people are likely to take the pill consistently. Justin Sullivan/Getty Images hide caption
Stringy particles of Ebola virus (blue) bud from a chronically infected cell (yellow-green) in this colorized, scanning electron micrograph. NIAID/Science Source hide caption
A culture of Clostridium botulinum, stained with gentian violet. CDC hide caption
Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention, talks with Doctors Without Borders staff during a visit in August to an Ebola treatment center in Monrovia, Liberia. Tommy Trenchard for NPR hide caption
Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, got his flu shot in September. J. David Ake/AP hide caption
A pharmacist pours Truvada pills, an HIV treatment, back into the bottle at Jack's Pharmacy in San Anselmo, Calif. Justin Sullivan/Getty Images hide caption