Jan. 8 (UPI) -- The death toll from a measles outbreak in the Democratic Republic of Congo has topped 6,000, the United Nations' primary health agency said.
The World Health Organization on Tuesday called the outbreak the "world's worst measles epidemic" and called for more funding to fight the spread of the virus.
Part of the problem is mistrust for medical professionals in some areas of the DRC, where measles vaccine rates remain low in locations guarded by armed militias, and workers' access to remote areas is difficult.
"We are doing our utmost to bring this epidemic under control," Dr. Matshidiso Moeti, the World Health Organization's regional director for Africa, said in a statement. "Yet to be truly successful we must ensure that no child faces the unnecessary risk of death from a disease that is easily preventable by a vaccine."
The DRC health ministry said the WHO helped vaccinate more than 18 million children last year in an effort to slow the spread. The WHO said 25 percent of measles victims in the DRC have been children under the age of 5.
"We recognize the government's engagement in the efforts to end the outbreak and we are grateful for the generosity of our donors, but we still need to do more," said Dr. Amedee Prosper Djiguimde, the officer in charge of the DRC's WHO office.
"Thousands of Congolese families need our help to lift the burden of this prolonged epidemic from their backs. We cannot achieve this without adequate finances."
Health officials say about $40 million is needed to implement a six-month plan to expand vaccinations to children between 6 and 14 years old and pay for other containment efforts like improved treatment, health education, community engagement, surveillance and response coordination.
"Lack of funding remains a huge impediment to successfully curbing the outbreak," the WHO said, noting that $27 million has been mobilized for the effort so far.