BENI, DEMOCRATIC REPUBLIC OF CONGO -- Health officials in eastern Democratic Republic of Congo confirmed a second case of Ebola on Thursday and said the latest flare-up of the virus appeared to be linked to the massive 2018-2020 outbreak.

A 42-year-old woman tested positive in the city of Beni on Wednesday, city health official Michel Tosalisana said.

The first confirmed case was a young boy who died of the disease https://www.reuters.com/world/africa/new-ebola-case-confirmed-eastern-congo-lab-report-2021-10-08 last week. Three of the boy's neighbors also died last month after after experiencing symptoms associated with Ebola, which can include severe vomiting, hemorrhaging and diarrhea.

"So far there have been more than 170 contacts listed around the first case, and with the confirmation of the second case, the listing of contacts will continue," Tosalisana told Reuters.

Steve Ahuka, a senior official at Congo's biomedical laboratory, told Reuters that preliminary sequencing indicated that the first confirmed case was the Zaire strain of the virus and was genetically linked to the 2018-2020 epidemic.

That oubreak, centered in Beni and the nearby city of Butembo, killed more than 2,200 people and infected more than 1,000 others.

Another flare-up linked to that outbreak lasted from February to May and killed six people. Flare-ups can be caused by latent infections that linger in the semen of survivors.

The two available vaccines against Ebola, manufactured by Merck and Johnson & Johnson, protect effectively against the Zaire strain and have been used to quickly bring other recent outbreaks under control.

Medics began vaccinating contacts of the first case in Beni on Wednesday using the Merck shot.