KAMPALA, Nov. 7 (Xinhua) -- Uganda on Wednesday started Ebola vaccinations for frontline health workers in the infected areas with support from the World Health Organization (WHO).

Yonas Tegegn Woldemariam, WHO country representative in Uganda, told Xinhua that the operation kicked off in Uganda's western district of Ntoroko.

"On top of close contacts of Ebola victims, frontline health workers face a very high risk of infection of Ebola as they care for patients," said Woldemariam.

At least 3,000 health care and frontline workers in the five high-risk western districts bordering the eastern Democratic Republic of Congo (DRC) are targeted, namely Kabarole, Bunyangabo, Kasese, Bundibugyo and Ntoroko, where there is an outbreak of the highly contagious disease.

"Uganda has taken a very huge step in mitigating the risk of Ebola among health workers. The vaccine is highly potent and it will protect workers effectively," Woldemariam said.

The ring vaccination exercise was originally set to begin on Monday but was postponed to Wednesday to allow for more time to reorient and train the vaccination team.

At least 2,100 doses of experimental rVSV-ZEBOV Ebola vaccine are currently available in the east African country, while supplementary doses have been requested, according to the WHO.

With high fatality rates ranging from 50 percent to 89 percent, the highly contagious Ebola virus could cause a range of symptoms including fever, vomiting, diarrhea, generalized pain or malaise and in many cases internal and external bleeding.