The UN's Health Agency Just Downgraded the Threat Level for the Deadliest Ebola Outbreak Ever

More than two years after the Ebola virus began its spread in West Africa, infecting nearly 29,000 people, the World Health Organization (WHO) has determined the outbreak is no longer a global public health threat and asked for travel bans to the affected countries to be removed.

WHO announced the development in Geneva today following a meeting that took into account recommendations from a committee of experts. Responsible for more than 11,300 deaths — mostly in Guinea, Liberia, and Sierra Leone — WHO's Director-General Margaret Chan said the deadliest Ebola outbreak in history had officially ceased to be a Public Health Emergency of International Concern.

This public health emergency was initially declared by the UN health agency in August 2014, months after Ebola claimed the life of its first victim in Guinea's forest region in December 2013. After a two-year-old boy in the prefecture of Gueckedou contracted and died of the hemorrhagic fever, the virus began its spread through the West African country, eventually crossing over the porous borders with Sierra Leone and Liberia by the spring of 2014.

"Ebola transmission in West Africa no longer constitutes an extraordinary event, that the risk of international spread is now low, and that countries currently have the capacity to respond rapidly to new virus emergences," Chan said at a press conference on Tuesday.

"The Ebola outbreak in West Africa is no longer a Public Health Emergency of International Concern."

Tuesday's determination comes after all three countries have managed to end transmission at least once, a milestone that requires 42 days without any new cases followed by a 90-day period of heightened surveillance. The incubation period for the virus is 21 days. Liberia first saw the virus halt its spread in June 2015, while Sierra Leone and Guinea followed suit toward the end of the year.

All three countries, however, have since seen small flare-ups of the virus, which are likely a result of the fact that the virus is believed to stay in survivors' systems for up to nine months — a sharp increase over previous estimates of 90 days. According to WHO, a total of 12 new clusters have been recorded in Guinea, Liberia, and Sierra Leone.

While Sierra Leone saw its latest flare-up on March 17, Guinea was hit with an Ebola cluster in the village of Korokpara this month that has since resulted in at least five deaths and more than 800 people put under quarantine. Officials said the fifth death was a man in Macenta prefecture who had previously traveled to Korokpara.

There were concerns that unsafe burial practices were used in at least one of the deaths in Guinea. A body is the most contagious just after death, making traditional burial procedures like washing and touching corpses a main cause of transmission. During the height of the Ebola outbreak, safe burial teams were deployed and public service announcements focused on educating the public about these dangers.

"A high level of vigilance and response capacity must be maintained to ensure the ability of the countries to prevent Ebola infections and to rapidly detect and respond to flare-ups in the future," she said.

In response to the most recent spread in Guinea, Liberia shut its borders, a policy that was put into place in 2014 when the outbreak was at its height. The three countries eventually reopened their official entry points in 2015.

While Liberia has beefed up its border measures, a key takeaway from the WHO meeting on Tuesday was the call to immediately lift any remaining trade or travel restrictions on the three countries.

At the height of the outbreak in 2014, images of Ebola-stricken patients lying in the streets waiting for hospital beds spread fear around the globe. Countries in the region like Mauritania and Gambia imposed restrictions, while places like Colombia and Haiti put all-out bans in place. While US lawmakers faced pressure to also institute a ban on travelers from West Africa, they ultimately settled on tighter screening and monitoring procedures at airports for travelers arriving from the affected countries.

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