They are likely to become dominant in the coming months, the European Center for Disease Prevention and Control (ECDC) estimates.
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Posted on 5/15/2022 4:43 PM Updated on 5/15/2022 5:16 PM
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Making way for a new wave of Covid-19 contamination? The European Center for Disease Prevention and Control (ECDC) urges European states in a statement released on Saturday 14. “The proportion in the European Union is currently small”, the text specifies, “but they will increase in the coming months dominant”, which could possibly lead to “a significant increase in the number of cases”. At this time, ECDC has no elements that indicate an increase in the severity of Covid-19 cases caused by these subvariants compared to the previous lines.
>> Covid-19: What we know about the two new Omicron subvariants discovered in South Africa
Consequently, the ECDC decided to move these two subvariants of interest to the higher category, that of ‘variants of concern’. Data are still limited, but BA.4 and BA.5 “appear to be more transmissible than the previous” subvariants of Omicron, France 24 epidemiologist Antoine Flahault had estimated. Their spike proteins include mutations L452R, which increase their transmissibility, and F486V, which are associated with a decrease in neutralization of antibodies.
Identified in late 2021, BA.4 and BA.5 are now the majority in South Africa. You could now assert yourself in Europe. “The Portuguese National Institute of Health estimated that BA.5 accounted for about 37% of positive cases on May 8, 2022,” notes ECDC, adding that this subvariant should become dominant in the country by May 22. Their competitive advantage “probably rests on their ability to evade the immune protection induced by previous infection and/or vaccination, particularly when this has waned over time”.
In France, according to Public Health France (SPF), the subvariant BA.2 of Omicron is still largely dominant with 99% of the sequences from the last survey. However, BA.4 and BA.5 have already been detected in France and are the subject of “enhanced surveillance”, writes the health authority in its epidemiological bulletin of May 5. SPF stated that by “Feb. May 2022 two cases of BA.4 and six cases of BA.5 in France were (were) confirmed and investigated”.