Zimbabwe's state newspaper says 14 people have died in a cholera outbreak and dozens have been sent to hospital.
Health officials say there have been at least 180 cases of cholera in the capital Harare and in some rural areas, but the situation is under control.
The Herald newspaper says the sale of meat in public areas has been banned as an added safety measure, and Harare's Mbare market closed down.
But Zimbabwean police told the BBC that they did not know of the meat sale ban.
Heath and Child Welfare Minister David Parirenyatwa told the Herald that investigations in Harare indicated that the three members of one family could have died from eating contaminated fish.
"We must be very strict on the health of our people," Dr Parirenyatwa said.
Zimbabwe cities were once among the most meticulously maintained in Africa but in recent years the authorities have struggled to clear rubbish and maintain sewer systems.
The squalor, combined with the recent heavy rains, has created the conditions in which cholera, a water-borne disease, can spread.
Last year, a government clean-up operation destroyed houses and left 500,000 homeless, according to a United Nations report.
Dr Parirenyatwa told The Herald the clean-up operation had helped to control the spread of the cholera outbreak.