2.4. Decontamination of surfaces and equipment

DNA amplicons present in the environment can cause widespread contamination of air, working surfaces, equipment, and personnel. Referring to current Chinese standards for disinfection techniques in healthcare settings (WS/T 367‐2012, China), we used a hypochlorite solution to achieve high‐level disinfection, alcohol to achieve medium‐level disinfection and UV irradiation to achieve decontamination. The following procedures for DNA decontamination were employed: (1) spraying a 75% ethyl alcohol solution into the air before cleaning the rooms; (2) irradiating the rooms with UV‐light for 1 hour; (3) wiping objects and equipment in the rooms with a hypochlorite solution to remove settled particles; (4) wiping equipment, such as disassembled centrifuge rotors or PCR instruments, with absolute ethyl alcohol; and (5) disinfecting laboratory coats before starting a new experiment. Note that separate sets of cleaning tools were used for each room and were not mixed. These steps were carried out twice per day for approximately 2 weeks.