Beijing's health authorities announced on Sunday that there has been no outbreak of cholera in the city, refuting rumors spread by cell phone text messages.

There are no cholera cases in Beijing caused by eating freshwater fish and shrimps, said Zhao Tao, a disease control official with the city's health authorities.

Aquatic products sold in Beijing are currently under scrutiny from municipal food supervision authorities and the quarantine department, Zhao said.

Zhao said the city's disease control and prevention center has intensified sample checks of aquatic products in supermarkets, restaurants and other trading places.

The center has detected no cholera bacteria in aquatic products sold in the city so far this year, the official added.

In partnership with mobile telecom operators, the city government on Saturday sent out one million short messages to refute scares about eating freshwater fish.

According to Zhao, last year the Beijing Disease Control and Prevention Center revised the cholera emergency scheme. There are now more than 300 hospitals in Beijing that provide outpatient enteropathy services, and all diarrhoea patients will be examined for traces of cholera virus.