Covid: expected waves to expect soon?

We are already talking about For the Omicron variant “No. 4” and even “No. 5”, two versions that look, according to first Reports previously posted to beginning of the monthSlightly more portable than previous versions. And two copies of vaccines against them It always seems capable To reduce serious cases leading to hospitalization.

In any case, it is too early to say whether BA.4 and 5 will actually lead to a rapid enough increase in cases that it then leads to an increase in hospitalizations. Since the vaccine is still partially effective, this also means that immunity acquired by those who have been infected with previous versions of Omicron can also slow re-infection – with one nuance: This scenario may vary greatly From one country to anotherDepending on the rate of vaccination.

But what is equally intriguing to experts now is another part of the statistics. This possibility is that the virus is evolving into predictable waves: an evolution that will therefore be less chaotic than in the first two years of the pandemic and could offer hope for the “management” of the virus that is also more predictable. Double reason: on the one hand, this partial immunity provided by the previous variable(s), which will eventually make it possible to predict how many months can be heard between two “waves”. On the other hand, the fact that the new sub-variants are not very different from their predecessors – unlike Omicron compared to the original coronavirus – which may be a sign that the virus has become like other respiratory viruses: it will always be present, it will continue to evolve, but not to the point of taking Our immune barriers are caught by surprise.

Thousands of new confirmed cases in South Africa / Source: Nature

According to previously published first reports, BA.4 and BA.5 appeared in mid-December 2021 and early January, respectively. The World Health Organization began talking about it in mid-April as Variables’ of importance (Not to be confused with “disturbing” variants.) At the time, the two strains accounted for 60-75% of cases in South Africa – and it is this speed that they say they are more transmissible – and they have been observed in more than a dozen other countries, particularly in Europe. the three The first Canadian cases It was announced on May 3.

However, there is still a lot to learn about these numbers 4 and 5. Among other things, observed last friday magazine report temper natureit is not yet known what mutation gives them this advantage that makes them more transmissible than BA.2 – which, in and of itself, It was more portable From the original Omicron.