The head of the World Health Organization said Wednesday that he expects the first doses of Ebola vaccine targeting the strain behind an outbreak in Uganda to arrive in the country next week.
WHO Director-General Tedros Adhanom Ghebreyesus said an expert committee convened by the agency had evaluated three experimental Ebola vaccines and decided they should all be tested in Uganda as part of the necessary research before being licensed.
"We expect the first doses of vaccine to be shipped to Uganda next week," Tedros said, adding that officials have now confirmed 141 cases, including 55 deaths, in the current outbreak, which is the first of the Sudan strain of Ebola in Uganda in more than 10 years.
The WHO chief said efforts to slow Ebola in Uganda have been largely successful. He said two districts have not reported any cases for 42 days, which is twice the maximum incubation period, suggesting that the virus is no longer present there.
But he noted that a ninth district has reported its first case in the past week.
WHO said government officials and partners were tracking more than 1,000 contacts of people sickened by Ebola, which is mostly spread through close contact with bodily fluids. The agency estimates the current fatality rate is about 40%.
While an effective Ebola vaccine against the Zaire strain exists, the Sudan strain is less common, and research into a possible vaccine against it has not been as advanced. The Zaire strain of Ebola has caused repeated outbreaks in Congo in recent years and also triggered the disastrous West Africa outbreak in 2014 that killed more than 11,000 people.
Still, WHO's emergencies chief, Dr. Mike Ryan, said Uganda's outbreak was likely controllable even without vaccines.
"We can stop this outbreak based on the current efforts," he said. "But vaccines obviously will help in the longer run." He acknowledged that the declining number of cases might make it more challenging to prove the experimental Ebola shots work, since they may not have enough people to gather necessary data.
"It's better for us to work towards generating the evidence rather than trying to second-guess the evolution of the outbreak," said Dr. Ana Maria Henao Restrapo, a WHO vaccines expert.
Earlier this month, vaccines alliance Gavi signed an agreement with Merck to secure 300,000 doses of its candidate Ebola vaccine for use in research and beyond.