The Democratic Republic of Congo's health minister resigned Monday after he was dismissed as head of the team tackling a persistent Ebola outbreak.

Last week, the World Health Organization declared the outbreak in eastern Congo to be an international health emergency.

BREAKING NEWS: The #Ebola outbreak in #DRC constitutes a public health emergency of international concern, citing concerning geographical expansion of the virus: WHO Director-General, @DrTedros following the IHR Emergency Committee’s recommendation #alert — World Health Organization (WHO) (@WHO) July 17, 2019

As of July 20, 1,643 people have died, among 2,484 confirmed cases of Ebola, a fatality rate of about 66 percent.

DRC President Felix Tshisekedi announced Oly Ilunga's dismissal Saturday, when the former health official said he was out of the country. A new task force which will report directly to the president will take over.

Illunga's resignation letter, which he released on Twitter, said the move could jeopardize efficiency, stability and consistency in the DRC's response to Ebola.

Suite à la décision de la @Presidence_RDC de gérer à son niveau l’épidémie d’#Ebola, j’ai remis ma démission en tant que Ministre de la Santé ce lundi. Ce fut un honneur de pouvoir mettre mon expertise au service de notre Nation pendant ces 2 années importantes de notre Histoire. pic.twitter.com/qEDAPkxR0B — Soutien au Dr Oly Ilunga (@OlyIlunga) July 22, 2019

He said another flashpoint was outside pressure to introduce a new experimental vaccine. The country has deployed hundreds of thousands of doses of a vaccine by Merck, a German pharmaceutical company. The World Health Organization (WHO) and others have encouraged the DRC to use another vaccine by Johnson & Johnson, an American company.

Both vaccines, and three others, are experimental.

At least 143,000 people have received the Merck vaccine during the current outbreak, which began a year ago. Though Merck has about 250,000 more full doses available, Bloomberg reported, the supply within the DRC is sporadic and stocks are typically 1,000 doses short.

FILE - A man receives a vaccine against Ebola from a nurse outside the Afia Himbi Health Center in Goma, July 15, 2019.

Another vaccine could help stop the spread of the virus, but health officials including Ilunga have resisted. They say introducing another vaccine could stoke fears within a populace historically suspicious of vaccines. The Johnson vaccine also requires two shots two months apart, which is difficult to administer as people flee.

It's unclear if the new task force will change the DRC's position on the second vaccine.

Jean-Jacques Muyembe Tamfum, director of the National Institute for Biomedical Research in Kinshasa, will lead the new Ebola task force. Tamfum was part of the team that investigated the first known Ebola outbreak in 1977, and was the first scientist to make contact with the disease and survive.

The ongoing outbreak is the second-deadliest on record, following one in West Africa during 2014 and 2015 that killed more than 11,000 people.