Abuja, Aug 25 : The ongoing cholera outbreak in Nigeria has killed 1,768 people in the country since its onset in January, a top health official said here. At a press conference on Tuesday, Chikwe Ihekweazu, head of the Nigeria Center for Disease Control (NCDC), said 47,603 suspected cases of cholera were recorded in 23 states and the Federal Capital Territory as of mid-August, reports Xinhua news agency. "The cases were reported from the beginning of the year. Persons aged five to 14 were mostly affected, 51 per cent being male and 49 per cent, female," Ihekweazu said, noting that the national multi-sectoral emergency system continues to coordinate the national response. The senior disease control official said the lack of potable water in rural communities, inadequate manpower for the cholera outbreak, as well as insufficient vaccine to be deployed to the affected local government areas in the country, are challenges being encountered in the cause of responding to the outbreak. Cholera is a highly virulent disease characterized in its most severe form by a sudden onset of acute watery diarrhoea that can lead to death by severe dehydration. The outbreak of cholera in Nigeria has remained persistent, occurring annually mostly during the rainy season and more often in areas with poor sanitation, overcrowding, lack of clean food and water, and areas where open defecation is a common practice. /IANS