A woman has her information registered before getting a booster shot of the COVID-19 vaccine at a vaccination site in Beijing, capital of China, Oct 17, 2021. (Photo: Xinhua)

Beijing reported two COVID-19 cases in late Monday afternoon traced to two schools in Chaoyang district, according to China Central Television.

One of the cases was found positive in the nucleic acid testing and the other one is said to be single-gene positive.

According to medical experts, the nucleic acid test is usually done by testing two genomes. The confirmed cases commonly have positive results for both genomes of the virus, which will be defined as COVID-19 cases.

This particular individual who tested single-gene positive, will be tested again by combining other indications including symptoms and imageological examination, said the medical expert.

According to local government, Chaoyang district where the two cases had triggered the emergency response on Monday in two schools -- one primary school and one middle school -- will conduct nucleic acid testing for all teachers and students.