The Ebola virus forms threadlike structures under the microscope. Cynthia Goldsmith/CDC hide caption
ebola
After testing negative for Ebola, Magdalena Nyamurungi returns home with a new set of belongings from the World Health Organization. Medical workers burned and buried her possessions when they suspected she was infected. B. Sensasi/Courtesy of WHO hide caption
A medical worker from the U.S. Centers for Disease Control and Prevention works at the laboratory where Ebola specimens from the Congo were tested at the start of the latest outbreak. Stephen Wandera/AP hide caption
A medical worker from the U.S. Centers for Disease Control and Prevention works at the laboratory in Uganda where Ebola specimens were tested at the start of the latest outbreak in the Democratic Republic of Congo. Stephen Wandera/Associated Press hide caption
A newly discovered disease in boa constrictors could provide the missing link in the latent Ebola virus. iStockphoto.com hide caption
The Ebola virus causes a deadly form of hemorrhagic fever. Frederick Murphy/CDC hide caption
The Ebola virus causes a hemorrhagic fever that can be deadly. Frederick Murphy/CDC hide caption