Nineteen people have died of Ebola in Congo as health officials plan to send an experimental vaccine to prevent the spread of the virus that killed thousands in West Africa a few years ago.

The World Health Organization said there have been 39 confirmed and suspected cases of Ebola over the past five weeks as the virus spreads across three rural areas covering nearly 40 miles in the northwest part of the country. Among the dead were three health-care workers. Health officials are following up with nearly 400 people identified as contacts of Ebola patients.

The global health agency announced last week its plans to send the vaccine, developed in 2016 by the pharmaceutical company Merck. Health officials hope that the vaccine, which was given to people in Guinea in West Africa during a trial in 2015, could be a game-changer in preventing Ebola from spreading, The Washington Post’s Siobhán O’Grady wrote last week. Among the 5,837 people who received the vaccine, called rVSV-ZEBOV, no one came down with Ebola 10 days after vaccination.

Tedros Adhanom Ghebreyesus, the WHO’s director-general, told reporters Monday that the agency has received permission from Congo officials to import the vaccine, which he hopes would arrive by the end of this week.

“Everything is formally agreed already. The vaccine is safe and efficacious and has already been tested. I think we can — all is ready now to really use it,” he said.

The WHO has a stockpile of 4,300 doses of the vaccine in Geneva, Stat News reported. Merck also has committed 300,000 doses of the vaccine for emergency use.

Ghebreyesus said he has traveled to the remote area to assess health needs.

“Being there is very, very important. If a general cannot be with its troops in the front line, it’s not a general. ... We have to go and show that that should really stop, and if my life is at risk, my life is not better than anyone,” said Ghebreyesus, a former Ethiopian health minister and the first African to become WHO’s director-general. “We have to be where the problem is.”

The WHO first learned of the outbreak May 8, when Congo's Ministry of Health confirmed two cases of Ebola in the town of Bikoro, now the epicenter of the outbreak and located in the country’s Equateur province, which has a population of about 2.5 million people.

“We are very concerned and planning for all scenarios, including the worst-case scenario,” Peter Salama, WHO's deputy director-general of emergency preparedness and response, said at a  United Nations briefing in Geneva on Friday, according to Reuters.

Transporting the vaccines to the affected area would be logistically challenging. Salama said the area is about 15 hours away by motorbike from the closest town and lacks the necessary infrastructure, Reuters reported. He said Friday that the WHO plans to send up to 40 experts by the weekend and clear an airstrip for supplies.

The country has experienced eight Ebola outbreaks over the past four decades. The most recent happened last year, when four people in Likati in the northern part of the country died. An outbreak in 2014 killed 49 people.

The largest Ebola outbreak in history ravaged the West African countries of Sierra Leone, Guinea and Liberia. Nearly 30,000 confirmed and suspected cases were reported. About 11,300 died from 2014 to 2016.

The WHO has acknowledged its bungled handling of the massive outbreak, saying it failed to recognize early that the West African countries that severely lacked health infrastructures were at imminent risk. According to a draft internal document obtained by the Associated Press, nearly everyone “failed to see some fairly plain writing on the wall.”

By early September 2014, more than 1,800 had died in Sierra Leone, Guinea and Liberia, and the global health community still had no coordinated response. President Barack Obama later dispatched up to 3,000 military personnel to West Africa, an effort with a $750 million price tag.

Symptoms of Ebola usually manifest eight to 10 days after exposure. These include fever, headache, diarrhea, vomiting and hemorrhage.

Here's how the virus spreads and how contact tracing works to stop outbreaks. (Gillian Brockell/The Washington Post)

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