The new crown epidemic is spreading across the country and many places such as Jilin, Shanghai and Guangdong are using antigen testing as an important auxiliary screening tool. However, recently, in Shanghai issued a biological company antigen kits within the swab package appeared hair as well as there is a significant yellowing phenomenon, triggering public concern about the quality of antigen testing swabs.
Swab quality concerns
It is understood that the production quality standards of swabs and masks are similar, divided into a class of medical devices and Class II medical devices, the latter with higher standards, the production process needs to do sterilization, so that the product is free of viable microorganisms. According to the sterile medical device "medical device production quality management specification", and human injury surface and mucous membrane contact sterile medical devices or single-package factory accessories, the end of the clean treatment, assembly, primary packaging, sealing the production area and the processing of parts without clean treatment production area should be no less than 300,000 cleanliness level.
Antigen reagent supporting a class I or class II medical device swabs, are in line with national standards. If the swab belongs to a class of medical devices, its production needs to the location of the municipal department responsible for drug supervision and management for the record; if it belongs to the second class, its production to be approved by the local provinces, autonomous regions, municipalities directly under the Central Drug Administration, according to law to obtain a medical device production license.
But even if it is a class of medical devices, the package with hair obviously does not meet the production quality specifications, the quality of the swab will directly affect the test results.
Compared to nucleic acid testing, antigen detection of nasopharyngeal swabs require a relatively large sampling area, and more soft, each manufacturer's reagents and supporting swabs to do experiments, so that the swab and its extraction solution formulation, test card detection capacity to match, to ensure that more virus samples are obtained per unit area, and thus ensure the sensitivity and specificity of the test.
It is worth noting that, in real-life applications, in order to ensure stable supply, companies will outsource swabs to multiple parties, not just choose one supplier. An antigen reagent will often be matched with several types of swabs. If the above statement is followed, that is, each swab needs to be matched to verify.
In addition, it is understood that depending on the sampling site, the swab material is different, such as nucleic acid testing of nasopharyngeal samples taken with a slender bendable flocked swab, antigen testing of pre-collection nasal samples with a straight rod of sponge swab. However, under the surge in demand, some manufacturers do not make a strict distinction between these.
Why do antigen testing swabs turn yellow?
The current yellowing of swabs around the world is due to the reaction between the sponge and chemicals such as disinfectant solution or potassium permanganate in the air, improper transport and high temperature during transportation can also cause yellowing.
