There are many listed companies involved in home-use COVID-19 testing business in my country, but only a few COVID-19 antigen testing products have been approved.

According to customs data, in November 2021, my country's new crown antigen detection reagents were mainly sold to Germany, the United Kingdom, the United States, Canada and Greece.

　　Starting from January 9, Tianjin has launched three rounds of nucleic acid testing for all employees in the city.

The Tianjin epidemic is the first large-scale Omicron encounter in China.

　　The detection of the new coronavirus is an important part of the fight against the epidemic.

On January 9, Tianjin Jiu'an Medical Electronics Co., Ltd. submitted the "Suggestions on Using Home Self-Testing Box to Realize 1+1 Prevention of New Crown Epidemic of Omicron" to Tianjin Epidemic Prevention and Control Headquarters.

If the self-test proposal can be adopted, it will mean that the way of screening people infected with the new coronavirus in China may change.

　　Home self-testing is also one of the means to control the epidemic

　　Zhang Yan, a professor at the School of Pharmacy of Tianjin University, said that the real-time fluorescence quantitative polymerase chain reaction nucleic acid detection technology currently used in screening patients with new coronary pneumonia, as well as the constant temperature detection technology that relies on DNA amplification, require professionals and professional equipment, including many Novel coronavirus antigen detection methods based on specific antibodies also need to use fluorescent labels to ensure the accuracy of detection.

These methods are highly dependent on professional equipment and professionals. Faced with large-scale nucleic acid screening, it is not only time-consuming and labor-intensive, but also has high economic and social costs.

Most importantly, universal testing increases the risk of exposure of the population being tested to susceptible environments.

　　Zhang Yan introduced that the home new crown self-test reagent uses antigen detection reagents, not nucleic acid detection reagents.

Since the antigen test is aimed at the virus N protein, and the virus mutation mainly occurs in the S protein, no matter how the virus mutates, the test results will not be affected.

　　"Antigen reagent combines the characteristics of nucleic acid reagents with high early diagnosis accuracy and antibody reagents for rapid detection. It can be detected on the first day of infection with the new coronavirus. It is easy to operate and does not require special equipment or instruments." Zhang Yan said that antigen detection The time from sampling to the result is generally within 20 minutes, and the accuracy rate is close to that of nucleic acid detection.

　　The use of nucleic acid testing (diagnosis) + home self-testing (screening) can more effectively block the spread of Omicron, and is a public health and epidemic prevention method to effectively control the epidemic.

　　早在2020年11月，英国就在利物浦试点以抗原试剂等方式开展首次全民新冠病毒普测。同时，也会对疑似病例配合采用更可靠的核酸检测。美、英等国家将抗原试剂作为新冠病毒筛查的主要手段后，筛查效率明显提高，因此目前很多海外国家正在大量采用家庭自测的方式进行筛查。

　　新型家庭自测系统更高效、低价

　　目前，家庭新冠自测试剂主要采用可以肉眼分辨显色的传统胶体金试纸条方法。该方法已经比较成熟，对新冠病毒检测的准确率也很高，但是也有其局限性。由于上样量有限，无法对病毒抗原进行扩增，可能导致检测的灵敏度较低。

　　因此，各国科学家都在寻找更高效、更低成本和更安全的新冠病毒家庭自测手段。

　　日前，张雁与美国哈佛大学等科研机构合作，研发了一种不需要任何电子、光学器件设备和操作技能培训的家用新冠自测系统。该系统最快可以在5分钟内检测出结果，并以直观的显色对比提供肉眼可见的结果，单片微流控芯片可以反复使用50次以上，极大降低了检测成本，非常适合普通家庭和个人检测使用。该成果于近日发表在国际期刊《Small》上。

　　据介绍，该研究团队创新性地使用了微流控芯片代替毛细管层析试纸条，上样量相比于传统的试纸条提高了数十倍。同时还规避了使用胶体金试纸条检测的常规方法对于低病毒载量样品容易漏检的风险。

　　张雁表示，用微流控芯片方法检测，在用户超过100例的双盲临床检验中，最终取得了对于普通新冠病毒和德尔塔变异毒株分别高达95.4%和100%的检测准确率。

　　“这种检测芯片使用了两种由不同抗体修饰的微米球和纳米球，颜色分别是白色和红色。”张雁介绍，当样本中没有病毒抗原时，红色纳米球可以快速被具有特定截留孔径的栅栏过滤，使得检测窗呈现微米球的白色，而当新冠病毒存在时，微米球和纳米球通过表面的抗体在病毒抗原介导下形成复合物，红色纳米球对白色微米球实现表面覆盖，从而使检测窗显示肉眼可见的红色。

　　由于芯片设计了逆流功能，完成检测后，在生理盐水或清水的冲洗下微球可以从原路返回，清空检测窗，从而可以反复使用数十次甚至上百次。

　　In addition, the home new crown self-test system is easy to operate and can be guided by video, suitable for adult-assisted collection of children aged 2 and above, as well as all adult self-test use.

Test results can be displayed within 20 minutes without leaving home.

　　Domestic promotion of new crown family self-assessment remains to be studied

　　At present, there are many domestic listed companies involved in the domestic new crown virus detection business, including Jiu'an Medical, Oriental Bio, Rejing Bio, Wanfu Bio, and Aotai Bio.

However, at present, my country has only approved a few new crown antigen detection products.

　　However, due to the particularly developed domestic nucleic acid detection, sampling points are everywhere, and the time for results is relatively fast, the method of antigen detection has not been widely used.

On the contrary, due to the lack of overseas nucleic acid detection capabilities, a large number of new crown antigen detection methods have been used, and most of the new crown antigen reagents produced by Chinese companies are sold abroad.

According to my country's customs data, in November 2021, my country's new crown antigen detection reagents were mainly sold to Germany, the United Kingdom, the United States, Canada and Greece.

　　According to industry insiders, due to the relatively small number of new cases in China and relatively scattered, it is difficult for reagent manufacturers to raise enough clinical trial cases in accordance with the current regulations of the State Food and Drug Administration.

However, according to the EUA registration requirements of the U.S. Food and Drug Administration (FDA), Jiu’an Medical, Oriental Bio and Aikang Technology, which have obtained the certification, have completed clinical trials of new crown antigen detection reagents in the United States.

For example, the iHealth new crown antigen home self-test OTC kit produced by Jiu'an Medical is one of the public health and epidemic prevention products widely used in the United States.

　　Zhang Yan pointed out that my country still faces a difficult problem in promoting the new crown home self-test, that is, the problem of supervision.

How to report the test results, how to avoid concealment, how to verify the authenticity and effectiveness of the test results in the background, how to conduct big data statistics, etc., are all issues that need to be solved before the promotion of the new crown home self-test.

However, with the normalization of new crown virus prevention and control, the promotion and popularization of new crown home self-testing still has certain value.