More than 80,000 people have now been infected with cholera in Zimbabwe's six-month-old outbreak which has killed 3,759, the World Health Organization (WHO) said on Friday.
About half of the patients who died from the water-borne diarrheal disease failed to reach any of the country's 365 cholera treatment centers, the United Nations agency said.
The proportion of deaths has been decreasing steadily since early January, but the fatality rate remains above the acceptable level in such an epidemic, according to the WHO.
The deadliest cholera outbreak in Africa in 15 years has also spread to neighboring countries including South Africa.
The intestinal infection spreads through contaminated food and water and can cause severe dehydration and death without proper treatment. While cholera is both preventable and treatable, an economic and political crisis in Zimbabwe has caused the near-collapse of health services.
"Given the outbreak's dynamic, in the context of a dilapidated water and sanitation infrastructure and a weak health system, the practical implementation of control measures remains a challenge," the WHO said.
