KINSHASA, Congo — Officials began vaccinating health workers and others on Monday in Bikoro, where Congo’s current Ebola outbreak was first declared at the beginning of May.

Congo’s Health Minister Oly Ilunga traveled to oversee the Ebola vaccinations of at least 10 people in Bikoro, where at least five of 12 Ebola deaths have happened.

Bikoro Hospital director Dr. Serge Ngalebato said he and other health officials were vaccinated for protection when treating Ebola patients.

“We who are on the front lines of caring for the sick. We are reassured,” he told The Associated Press by telephone. Monday’s vaccinations included three doctors at Bikoro Hospital, two health experts, two nurses, one representative of women in the community and one pygmy representative, he said.

The procedure, which is voluntary, will take time and follow up to make sure there is a positive response, Ngalebato said.

Congo’s vaccination campaign, which began in Mbandaka last week, is targeting more than 1,000 health workers and contacts of the sick in three health zones.

As of Monday Congo updated that there were 54 cases of hemorrhagic fever: 35 confirmed Ebola cases, 13 probable and six suspected.