A little over a year ago, the world was gripped by Ebola panic. A Spanish nurse who had been treating an Ebola victim in Madrid tested positive for the disease — the first case outside West Africa. A few days later, two American nurses who cared for America's first Ebola patient, Thomas Duncan, would test positive, too.
The panic in America faded away, but even as Ebola dropped from the front pages, the virus continued to snake through West Africa. To date, Ebola spread to some 28,000 people and killed more than 11,300.
But today it seems the worst Ebola epidemic in history might be over: The World Health Organization reported that there have been no new cases of Ebola for 42 days (two 21-day incubation periods for the virus, used to measure whether viral transmission has stopped.)
But the agency also warned that there may still be "flare-ups" of the disease in the coming weeks.
"Detecting and breaking every chain of transmission has been a monumental achievement," said Dr. Margaret Chan, WHO director general, in a statement. "But our work is not done and vigilance is necessary to prevent new outbreaks."
So far, the WHO reported, there have been 10 flare-ups that were not part of the original outbreak, "likely the result of the virus persisting in survivors even after recovery."
Health officials are indeed worried about the transmission potential of survivors, who can spread the virus through semen and other bodily fluids months after they are cured. That's because Ebola has been found to persist in special sites on the body, such as the eyeballs and testicles, where the immune system has a harder time flushing out the virus.