Guinea No Longer Free of Ebola: 2 New Cases
A 2014 photograph of a West African Ebola treatment center.
Credit: CDC

Two new cases of Ebola have been confirmed in Guinea, the first in the country since it was declared Ebola-free in late December, according to the World Health Organization.

The cases were discovered after officials investigated three unexplained deaths in the rural village of Koropara. Family members of the deceased were tested for Ebola, and two people — a woman and her 5-year-old son — tested positive for the disease, WHO said in a statement. (The organization did not say whether the people who died also had Ebola.)

Guinea's Ebola outbreak was declared over on Dec. 29, 2015, but officials said they expected that additional, small outbreaks of the disease would still occur in Guinea and the two other West African countries — Liberia and Sierra Leone — where the outbreak raged for two years.

The WHO stressed in its statement that these three West African countries "are still at risk of Ebola flare-ups, largely due to virus persistence in some survivors, and must remain on high alert and ready to respond." (Although the Ebola virus disappears from most of the body after a person is cured, it can remain in the semen of male survivors for as long as a year, according to the WHO.) [The 9 Deadliest Viruses on Earth]

The new cases in Guinea were confirmed on the same day that WHO declared an end to the most recent Ebola flare-up in Sierra Leone. That flare-up began in mid-January when two people were found to be infected with Ebola.

It has now been more than 42 days since the last person to have Ebola in Sierra Leone was cured of the disease, WHO said. (Health officials typically wait 42 days to declare a country free of Ebola because this is twice as long as the 21-day incubation period of the virus, or the time it takes for a person with the virus to start showing symptoms.)

Overall, the Ebola outbreak in West Africa, which started in Guinea in late 2013, resulted in more than 28,600 cases of the disease, and 11,300 deaths.

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