A medical worker administers a cholera vaccine to a patient in Juba, capital of South Sudan, Sept 27, 2017. [Xinhua]

UN humanitarians on Monday reported a 70 percent surge in cholera cases in strife-torn Sudan, which has prompted a scale-up of response.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) warned the cholera outbreak continues to worsen, with the latest surge tallied over just the past three weeks.

"As of today (Monday), nearly 5,200 suspected cases of cholera, including more than 160 deaths, have been reported in nine states in Sudan since Sept. 26," said OCHA, citing data from Sudan's Federal Ministry of Health and the World Health Organization (WHO).

The United Nations and humanitarian partners continue to scale up the response to the outbreak, including by supporting the detection and treatment of cases and addressing water, sanitation and hygiene issues, said OCHA.

The humanitarians said nearly 2.2 million oral cholera vaccines were administered in the worst-affected states, it said.

"About two-thirds of Sudan's population lacks access to health care, and more than 70 percent of health facilities in conflict areas are out of service," OCHA said. "Since the start of the war in April, the WHO has verified 60 attacks on health care in Sudan."