YAOUNDE, Cameroon (AP) -- UNICEF says more than 300 people have died in the West African nation of Cameroon from the country's worst cholera outbreak in 20 years.

UNICEF said Monday that more than 4,500 people have been sickened by the highly contagious infection that causes diarrhea in victims, leading to severe dehydration.

At least 331 people have died since the outbreak began in May, and officials fear it will spread further when children return to school this week after summer break.

UNICEF is launching an informational campaign in schools to teach children about good hygiene to prevent the disease from spreading.

Cholera also has killed several hundred people in Nigeria this year and more than 40 in the neighboring country of Chad.

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