Countries are being asked to step up assistance to the Democratic Republic of the Congo (DRC) which is facing the world's worst measles epidemic, with more than 6,000 deaths since the start of last year.
The World Health Organization (WHO) on Tuesday said some 310,000 suspected cases of the disease have been reported since then.
The UN agency and its partners have worked with the authorities to vaccinate more than 18 million children under five during 2019. However, coverage remains low in some areas, with under-fives accounting for a quarter of cases.
"We are doing our utmost to bring this epidemic under control. 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", said Dr Matshidiso Moeti, WHO Regional Director for Africa.
Challenges to response
Last month, the UN agency trained 60 health workers to conduct community engagement, health education and surveillance, who will be deployed this week.
The outbreak is occurring as the DRC is battling other epidemic-prone diseases, including its worst ever Ebola epidemic, in the east of the country.
WHO said the situation is further "aggravated" by weak public health systems and difficulty in accessing vulnerable populations, while insecurity has hampered efforts in some areas.
So far, more than $27 million has been mobilized for the response. However, another $40 million is needed for a six-month plan that would extend vaccination to children aged six to 14 years.
The funding also will help with improving treatment, health education and community engagement, in addition to strengthening the health system, among other measures.
"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 Amédée Prosper Djiguimdé, Officer in charge of WHO's office in the DRC.
"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."