Antigen test reagents are approved more quickly, and epidemic prevention policies are optimized to expand application scenarios

In March 2022, the Comprehensive Group of the Joint Prevention and Control Mechanism for the Novel Coronavirus Pneumonia Epidemic of the State Council issued the 'Application Plan for Novel Coronavirus Antigen Testing (Trial)', promoting the monitoring model of 'antigen screening and nucleic acid diagnosis', adding antigen testing as a supplement to nucleic acid testing. Subsequently, the novel coronavirus antigen testing was temporarily included in medical insurance.

In June 2022, the Comprehensive Group of the Joint Prevention and Control Mechanism of the State Council for the Novel Coronavirus Pneumonia Epidemic issued the 'New Coronavirus Pneumonia Prevention and Control Plan (9th Edition)', adding antigen testing as a supplementary means of epidemic surveillance. Grassroots medical and health institutions can increase antigen testing for suspected patients and people in medium- and high-risk areas during epidemic response.

Recently, the Comprehensive Group of the State Council's Joint Prevention and Control Mechanism for the Novel Coronavirus Pneumonia issued 'Twenty Measures' and 'New Ten Measures', actively optimizing and improving prevention and control policies. Among these, nucleic acid testing has been further optimized, stipulating that full-scale nucleic acid testing is not conducted by administrative region, further narrowing the scope and frequency of nucleic acid testing. Antigen testing can be carried out according to the needs of epidemic prevention work.

In December 2022, the Comprehensive Group of the Joint Prevention and Control Mechanism for the Novel Coronavirus Pneumonia Epidemic of the State Council issued the 'Antigen Detection Application Plan for Novel Coronavirus', which specifies the applicable population for antigen testing: 1) individuals with the need for self-testing; 2) people in crowded places such as large enterprises, construction sites, universities, etc.; 3) elderly people at home and in elderly care institutions. The plan also details the testing frequency and reagent reserves for the second and third categories of individuals, clearly stipulating that crowded institutions should reserve an appropriate amount of reagents for testing; elderly people at home and in elderly care institutions should undergo testing twice a week, and grassroots medical institutions should reserve antigen reagents according to 15-20% of the total service population.

Against the backdrop of optimized COVID-19 prevention policies, many experts believe that the epidemic will peak within a month and last for about three months. Feng Zijian, former deputy director of the Chinese Center for Disease Control and Prevention and a member of the expert group of the National Joint Prevention and Control Mechanism against COVID-19, stated that ultimately, 80% to 90% of people may experience infection. This indicates that the COVID-19 antigen test market will expand rapidly. In the recent wave of infections, assuming all infected individuals use antigen tests five times during their infection cycle, the demand for antigen tests is also about 6 billion yuan. The price of an antigen on the market is mostly between 3 to 5 yuan, and the market size of antigen tests is conservatively estimated to be hundreds of billions.

Antigen testing has advantages over nucleic acid testing in terms of avoiding waste of medical resources and alleviating insufficient distribution of medical resources. The feature of getting results in 15 minutes for self-testing can also avoid the risk of cross-infection due to queuing for nucleic acid testing. There is still great potential for the application of COVID-19 antigen testing. With the implementation of policies, its scope of application is gradually expanding.

Antigen test kits are widely used by people suspected of having COVID-19 infections, mostly during the acute phase of infection, when flu-like symptoms such as fatigue, fever, and cough appear. However, recently, with the high-frequency use of antigen test kits, there have been public reports of cases where individuals with obvious symptoms still tested negative, or those who tested positive for nucleic acid but negative for antigen.

For symptomatic individuals with negative antigen test results, this is because antigen test kits rely on the viral load in the sample for detection. When nasal or pharyngeal swabs do not collect enough viral load, the test can be 'inaccurate'. Generally, when a person has just been infected with the novel coronavirus, due to the low viral load, although the patient may already be experiencing discomfort symptoms, the antigen test result may still be negative. As the virus continues to replicate within the body and exceeds the minimum viral load requirement for antigen testing, the result becomes positive, usually 2 to 3 days after infection. At this time, the patient typically also experiences obvious symptoms such as fever, general body aches, and coughing. Additionally, for some mild cases and asymptomatic carriers, due to the low viral load and detox in their bodies, the viral load collected from nasal or pharyngeal swabs is also low, and it may take 5 days or even longer after infection before the antigen test kit can detect it.

In addition, since antigen testing is usually conducted by individuals collecting and testing their own samples, there may be non-standard operations, which can also affect the accuracy of the antigen test results.

The epidemic has catalyzed the registration approval and application of domestic antigen testing products. As of December 2022, the National Medical Products Administration (NMPA) has approved 42 COVID-19 antigen test kits, including latex method, colloidal gold method, and fluorescence immunoassay method. In addition, to support the supply of COVID-19 antigen test kits for epidemic prevention and control, the National Medical Products Administration recently issued a document extending the validity period of registration certificates for approved COVID-19 antigen test kits by six months on top of the original validity period.

In response to the continuous demand for COVID-19 antigen test kits, several listed companies have stated that their production capacity will gradually increase:

• Yahui Long stated that the company's production capacity will gradually increase from 4 million doses to 7.5 million doses.

• Wanfu Biotech stated that the company will make dynamic adjustments in a timely manner based on factors such as market demand, delivery requirements, and inventory status to meet the market's testing needs.

• Lizhu Group stated that the company is currently increasing production to ensure antigen supply.

• Mingde Biotech stated that the company has experienced the ramp-up of production capacity for COVID-19 antigen test kits in the first half of the year and possesses the ability to quickly adjust its production capacity. The company ensures the production of antigen test kits through various methods such as actively recruiting workers and operating multiple shifts.

Although there is currently a situation where COVID-19 antigen test kits are 'hard to come by' in some areas, China has sufficient production capacity for COVID-19 antigen test kits. Forty-two products have been approved, and the Ministry of Industry and Information Technology has provided key support to all antigen test kit manufacturers. The production capacity of antigen test kit products will continue to be released, and market demand will also be gradually met.

At present, the epidemic is in its initial phase of relaxation, application demand has begun to emerge, and local governments and institutions are increasing procurement. After the supply-demand balance is achieved in the later stages, market development will reach a relatively stable state.