Aug 9, 2018 - Health

Congo trying to stem Ebola outbreak with experimental vaccine

Data: Ministry of Health DRC; Chart: Andrew Witherspoon/Axios

The Democratic Republic of the Congo started using an experimental vaccine against the deadly Ebola virus yesterday after identifying it as the virulent Zaire strain. The latest outbreak has spread to a conflict region and is suspected of killing at least 36 people during its first week.

Why it matters: Testing and approving an Ebola vaccine is a priority for global health officials as further outbreaks are expected — and the U.S. hopes to get the Food and Drug Administration to consider approval for a vaccine in 18 months or so.

"As I said before in May [during prior DRC Ebola outbreak], 'It's not over yet, folks, because this is going to come back.'"
— Anthony Fauci, director, National Institute of Allergy and Infectious Diseases

Background: Out of the four Ebola strains that humans can catch, the Zaire strain currently in DRC is the deadliest — but it's also one targeted by most of the vaccines and treatments, Fauci tells Axios. The DRC and surrounding countries often have outbreaks because they have a "reservoir" of infected bats and non-human primates that can transmit the disease to humans — "so this is not a fluke," Fauci says.

Driving the news: DRC officials now are vaccinating with 3,220 doses of the experimental rVSV-ZEBOV vaccine, wielding it as a ring vaccine where the circle of people in contact with the infected are vaccinated as well. They have requested more.

This is the 10th such outbreak in the country since 1976, but the positive side of this is that "they are pretty good at knowing how to deal with Ebola," Fauci says.

However, there are challenges that health workers have not had to deal with in other outbreaks, namely that the border region between the DRC, Uganda and Rwanda is home to active rebel groups, about 1 million displaced people and the largest UN peacekeeping force in the world.

"The real disturbing aspect is that it is now in a [conflict] zone... it's difficult to get health care workers in and it's dangerous because there are people who are terrorists who target health care workers often," Fauci says.

Hope for the future: Nevertheless, there are several promising vaccines and therapies out there — all of them experimental right now, he says.

  • While DRC health officials were unable to comment by publication, Fauci says he hopes the authorities decide to conduct a protocol-driven, randomized trial without a placebo to help gather more information on the different vaccines or treatments.

Current experimental treatments, some of which may be tried in DRC, include:

1.Vaccines: Two promising ones are rVSV-ZEBOV and Ad26.ZEBOV with a MVA‐BN‐Filo boost. Both of these are currently undergoing testing for safety and its ability to generate a response from the immune system, as well as other factors.

  • The rVSV-ZEBOV vaccine, which is currently being used in DRC, could possibly be considered for FDA approval starting in 18 months, depending on the trials and the regulator itself, Fauci says.
  • The Ad26.ZEBOV with a MVA‐BN‐Filo boost is being evaluated in two large trials.

2. Other treatments: ZMapp and mAb114 are antibodies designed to protect the body against the virus. Favipiravir and remdesivir (GS-5734) are anti-viral agents currently used against other viruses that are now being studied for their efficacy against Ebola.

Editor's note: This piece was corrected to take out the cAd3-EBOZ vaccine and the anti-viral brincidofovir (which are in small studies), and to add in Ad26.ZEBOV and remdesivir .

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