[ad_1]
It was what was expected, but it was not what happened. On January 12, variant B.1.1.7 represented 8% of the genomes analyzed and, at that time, Insa’s team predicted that, until February 14, the prevalence of the British variant in Portugal could reach as high as 65%.
“We completely deviated from the projected curve at that time,” said João Paulo Gomes, showing a graph at the Infarmed meeting. “We stopped growing exponentially and began to enter a plateau,” he added without, however, mentioning the current prevalence. In the week of January 10-19, 16% of the samples analyzed were of the British variant – which was in line with the 14% forecast for that time, the researcher said.
During the presentation, João Paulo Gomes hinted that the country’s success in containing this variant may be related to the adoption of restrictive measures before B.1.1.7 became dominant, unlike the UK. The British only gave the warning in mid-December, when the variant’s presence rose sharply to 60%, and the most severe lockdown was only implemented in early January, when the variant already accounted for 80% of cases. in the country.
“Cases associated with the UK variant typically have a viral load about 20 times higher than cases with the other variants,” said the Insa researcher to justify the higher transmissibility. Mutations make the virus have a greater affinity with our cells (and infect more), which leads to the production of more copies of the virus (higher viral load), which end up being expelled in our social contacts. But in Portugal, this variant does not seem to attack some age groups more than others.
INSA. The UK variant can reach 60% of positive cases in early February in Portugal
In two months, from December 1 to February 7, the Unilabs laboratory carried out more than 200 thousand diagnostic tests, which established an alliance with Insa for the identification of the British variant. Of the 49,127 positives, 8,657 corresponded to variant B.1.1.7. Taking into account the number of tests carried out by this laboratory, this variant may have thus caused more than 120 thousand cases in Portugal.
João Paulo Gomes began the presentation by recalling that the The South African (B.1.351) and Brazilian (P.1) variants also represent an “additional concern”. Not only do they have the same mutation as the British variant, N501Y, affectionately called Nelly, but they have another mutation, E484K, also called Erik, which potentially allows the virus to escape the immune system, i.e. neutralizing antibodies (including vaccines). , according to some experts, although the issue greatly divides researchers).
United Kingdom, South Africa and Brazil. Erik and Nelly, the mutations that make fear of the three new variants of the coronavirus
The good news, at least judging by the data released by Insa, is that only two cases of the South African variant, both in December (and fully contained), and none of the P.1 variant – the one that is causing a new wave of the pandemic in the city of Manaus, with many more cases than the first.
The mysteries of Manaus. Do you have a more aggressive variant of the virus, have you lost herd immunity or have you never had it?
What João Paulo Gomes did not mention, but which can be found in the institute’s report, is that Five cases of variant P.2 have already been detected, another Brazilian variant, three of which in the second week of January (0.6% of cases). This is a variant that is still little known, but enough to keep an eye on: it has the Erik mutation, which allows the immune system to escape, and has been associated with reinfection cases in Brazil.
[ad_2]
