Medical workers work in a COVID-19 testing lab in east China's Shanghai, April 15, 2022. Photo:Xinhua

Central China's Hunan Province will roll out antibody testing services to the public starting from February 7, becoming the latest region in China to conduct such testing after cities such as Beijing and Wuhan in a bid to get an overall picture of immunity among the population and resistance against secondary infection.

The antibody testing service will be a user-pays model and cost 32 yuan ($4.74) per test. The daily reservation quota limitation is 100, according to a statement released by the Hunan provincial disease prevention and control center.

"The test is helpful to scientifically evaluate the immune status of COVID-19 recovery among the public and their resistance to secondary infection. It can serve as a reference to auxiliary diagnosis of COVID-19 infection, and receiving vaccination," the center noted.

Beijing is also set to conduct serum antibody investigation for novel coronavirus during February and March this year. A total of roughly 5,000 people will be randomly chosen across all of Beijing's sub-districts, requiring information of their nucleic acid and vaccination status, to complete the investigation.

Similar antibody testing has been conducted in Wuhan by the city disease prevention and control center since January 15.

The antibody investigation should be conducted across the country to obtain a full picture of infection among the country's population, an expert from the Chinese Center for Disease Control and Prevention (Chinese CDC), who requested anonymity, told the Global Times.

According to the China CDC, some provinces have set up mobile applications to collect antigen testing results provided by the public where people can upload their test results on a voluntary basis.

It showed the testing amount in each province was quite low, and demonstrated a downward trend. Testing amount dropped from a peak of 1.89 million on December 19, 2022 to 105,000 on January 23, 2023, rebounding to 132,000 on January 30.

The positive rate of antigen detection increased rapidly from December 9, 2022, reached a peak on December 22, then fluctuated and decreased, and fell to the lowest level on January 30, 2023 with positive rate standing at 2.2 percent, data released by the China CDC on February 1 showed.

This investigation will answer some important questions, for example, how many individuals are asymptomatic, as well as the antibody levels of people inoculated with different vaccines. If the sample is big enough, it will also tell health officials the proportion of COVID-19 patients with severe symptoms and even the number of deaths, the expert said.

"This [serum antibody] is important for the country to prepare for any further outbreak. The next wave won't overwhelm the medical system, but it will help us better prepare for the next wave and possible other endemic to come," the anonymous CDC expert said.

Global Times