The Centers for Disease Control and Prevention's PulseNet service monitors clusters of sickness linked to potentially dangerous strains of foodborne pathogens such as E.coli or salmonella. Reed Saxon/AP hide caption
This image was posted by NASA to the agency's official Instagram account. NASA/Getty Images hide caption
The Eagle Mountain Church in Newark, Texas, was linked to at least 21 cases of measles this year, mostly in children. LM Otero/AP hide caption
Clouds of nicotine-laced vapor are getting more popular with teens. Mauro Grigollo/iStockphoto.com hide caption
There has been more progress in lowering deaths from heart attacks and strokes among people who qualify for Medicare than those who are younger. CDC hide caption
Black-legged ticks like this can transmit the bacterium that causes Lyme disease. CDC hide caption
Small declines in obesity among young kids could help stem bigger problems in the future. Ocean/Corbis hide caption
Is it safe? The water in many public pools is contaminated with E. coli, a study finds. iStockphoto.com hide caption
A new study from the Centers for Disease Control and Prevention finds no link between the number of vaccinations a young child receives and the risk of developing autism spectrum disorders. Jeff J. Mitchell/Getty Images hide caption
A woman uses a cellphone while driving in Los Angeles in 2011. Damian Dovarganes/AP hide caption
Klebsiella pneumoniae, seen here with an electron microscope, are the most common superbugs causing highly drug-resistant infections in hospitals. Kwangshin Kim/Science Source hide caption
Infections With 'Nightmare Bacteria' Are On The Rise In U.S. Hospitals
Kimberly Delp gives a flu shot to Carleen Matthews at the Homewood Senior Center in Pittsburgh, Pa., last September. Andrew Rush/AP hide caption
More than 400 guns, including these three, were turned in during a Dallas gun buyback program in January. But determining the effectiveness of such programs is difficult due to limits on gun-related research. Tom Pennington/Getty Images hide caption