The recent outbreak of group norovirus infections across the country coincides with the peak season for the virus, and authorities warn that preventive and disinfection measures are critical.

The National Disease Control and Prevention Administration has recently released a technical guideline for the prevention and disinfection of norovirus infections in schools and other key areas, including kindergartens and elderly care centers. The guideline stressed that those infected should immediately be isolated, and efforts to disinfect affected areas should be made promptly.

The guideline emphasized that norovirus is highly contagious. It can affect individuals of all age groups, and immune protection following infection tends to be short. Group infections are particularly common in crowded environments such as schools and care centers for children and the elderly.

In early November, students from three classes at a primary school in Shiyan, Hubei province, were infected, leading to a weeklong suspension of classes, according to an official from the local education bureau.

In Pu'er, Yunnan province, at least 18 students at an elementary school were diagnosed with the illness in mid-October, with symptoms including vomiting and abdominal pain.

Also that month, a kindergarten in Xi'an, capital of Shaanxi province, reported 48 infected children, who had symptoms such as vomiting and diarrhea, local authorities said.

According to the guideline, norovirus is highly resistant to common disinfectants such as 75 percent alcohol and hand sanitizers. High-level disinfectants and proper physical disinfection methods should be used to effectively eliminate the virus.

When coming into contact with infected individuals, it is recommended to use disinfectants containing chlorine to clean areas contaminated by their vomit or excrement, while avoiding direct exposure to the contaminants.

In addition to disinfection, the guideline emphasized the importance of daily hygiene practices, such as washing hands properly and cooking food thoroughly.

The peak season for norovirus typically spans from October to March each year. Vomiting is a common symptom among infected children, while adults are more likely to experience diarrhea.

The virus is primarily transmitted through the ingestion of contaminated food or water, contact with surfaces or items contaminated by infected individuals and exposure to airborne aerosols from their vomit.

Li Shangyi contributed to this story.