Mutations: More accurate tracing

Identifying mutations of the Kovid-19 virus in a “more accurate” and “more reactive” way, it was initiated to prevent the progression of troublesome forms of coronavirus on French soil. “Today, we are seeing a growing variety of variations, which means that looking specifically for one, two or three variants will no longer meet the need to monitor the problematic variants of SARS-Covey-2,” a public official explained on Thursday, June 10th. Health France. “Any positive test should always lead to screening”, but now there is the idea of ​​”following mutations of interest found in a large number of variations”, says Sibyl Bernard-Stoeklin of the Department of Infectious Diseases. Public Health Agency. Screening involves the use of specific screening kits, which are “screen” positive PCR tests to determine if the patient is a carrier of the SARS-COV-2 virus. This method came into effect last January to identify the emergence of the “alpha” variant (formerly the English variant) that was first identified in the United Kingdom in January 2020 and now prescribes AFP for most of the positive diagnoses in France. The kits used to identify the types of anxiety “Kilta” (first identified in South Africa) and “Gamma” (originated in Brazil) are the “Delta” variant (from the virus sub-genus India). This strategy makes it possible to get results faster than sequencing, which involves analyzing all the RNA of the next virus, but it has its limitations. The first hurdle: French analytical laboratories have different kits, all of which do not detect the same mutations. In addition, a positive result indicates a “suspicion” of a variant of anxiety, but only the sequence is certainly possible. Finally, since the same mutation can be present in many variants, the same screening result can be attributed to different variants according to laboratories. From the end of May, the labs began equipping themselves with new screening kits, which were commissioned from mid-June. Public Health France stopped the distribution of variants in the territory on June 10 according to the old method to switch to the new nomenclature. Three variants called E484K, E484Q and L452R were selected. Especially in the “beta”, “gamma” and “delta” varieties, they are considered “of interest” because they also have an effect on immune avoidance, transmission or infection severity. The list is limited to three, because “more mutations are added to the screening kit, the sensitivity decreases”, underlined by Sibyl Bernard-Stoeklin.