Southwest China's Chongqing municipality has realized 100 percent up-to-standard disposal of medical wastewater and there has not been outbreak caused by the medical sewage, officials from the Chongqing Municipal Health Commission told a news conference on March 30.

Officials said medical sewage is not equal to general sewage, as its sources and composition are complex -- even containing pathogenic microorganisms, toxic, harmful physical and chemical pollutants and radioactive pollution.

Without effective treatment, it will become a potentially dangerous channel for the spread of epidemics and seriously pollute the environment.

According to local officials, during the COVID-19 epidemic, about 3,500 tons of infectious disease sewage were produced every day by four designated treatment hospitals and 48 designated hospitals in Chongqing.

"In accordance with the principles of risk control and rendering things harmless, we required designated medical institutions and relevant temporary isolation sites to collect sewage and wastes centrally -- sterilized and disinfected them up to standard and then discharge them into the pipeline network to enter the sewage treatment plant," Chongqing Municipal Health Commission official Liu Liangqing told the news conference.

He added that all designated hospitals have increased disinfections, the frequency of drug disinfections, frequency of drainage monitoring and increased inspections of facilities and equipment.

In temporary medical isolation points or isolation wards, they have increased infectious sewage treatment equipment according to local conditions. They have built temporary sewage treatment tanks and adopted chlorination, peracetic acid and other measures to strengthen disinfection.

In addition, the monitoring of total residual chlorine and pH was strengthened in medical institutions receiving confirmed COVID-19 patients.

Between 2018 to 2020, Chongqing completed the installation on average of 60 sewage treatment facilities for primary medical and health machines per year -- and the marked improvement in the discharge of medical wastewater has improved the city's medical sewage treatment capacity, officials said.