How dangerous is the Type BA4 Variant of Omicron?

The Spread of Omicron

A new, even more contagious variant of the "omicron" strain has entered the World. We are talking about type BA4. The mutation was first recorded in April-May in some European countries, South Africa and the United States. Now, 95% of new cases of coronavirus occur due to Sub-variant of Omicron, namely its earlier sub-variant BA.2.

Role of Immunity

Another mutation will not be able to spread so actively and all because a good immune layer has formed in people who have previously been ill and vaccinated. Despite the fact that the new omicron subspecies is more contagious, this is unlikely to lead to a sharp increase in the number of infected, experts said:

Decline in the World curve;

“We are talking about the S-protein, the variants differ precisely in these mutations, but Omicron has a very large number of mutations, and its variants retain the same ones, adding more precisely in the S-protein. What happens in other proteins is impossible to say for sure. The spread of a new subvariant may lead to an increase in incidence, but it is unlikely to be significant. This is clearly seen on the world curve. The first peak is grandiose, it goes to 3.5 million, the second is somewhere around 1 million, the next one is about 800 thousand, now it is at the level of 500 thousand and continues to slowly slide down.

The first high prong is "omicron" B.1, the second is B.2, the third has appeared now - these are the third, fourth, fifth options. We are taking anti-epidemic measures, forming an immune layer. There is also another factor. Here's a variant - as it infects people and is transmitted from one to another, with each cycle of reproduction, mutations gradually accumulate in different places of the genome, not only in the S-protein, and the virus weakens. And that's what's causing the decline."

In May, the World Health Organization (WHO) noted that the number of countries where new Omicron sub-variants are being distributed is growing. Although the number of cases in general is decreasing. For example, at the end of last month, this figure fell again, by 11%. At the same time, an outbreak of COVID-19 was recently recorded in Shanghai. The city authorities have announced testing of almost all residents, which is about 25 million people. Just last week, a two-month quarantine was lifted there. Israel also recorded an increase in infections this week and recommended that certain categories of citizens wear masks.

But in other regions , it is not worth expecting tougher coronavirus measures even with the appearance of new mutations of the “omicron”, believes experts: “The first cases were recorded in South Africa, but we did not see any global outbreak there. The increase in the number of cases was not followed by an increase in hospitalizations and deaths. We do not see any dramatic surge in the US either, although, based on the statistics of the Centers for Disease Prevention and Control, the presence of the BA.4, BA.5 strain has increased from 1% in May to 7.5% at the moment. Its share among others is about 13%.

The appearance of BA.4 subtypes in Russia, of course, causes some concern, however, one should not expect dramatic changes.

New Restrictions

We recently received a message from Israel that they are again going to introduce a mask regime in crowded places, although the country was one of the first to cancel it. In China, rather tough restrictive measures periodically arise when there are new surges. There are no reports of BA.4, BA.5 variant in Israel and China. Since May, more or less active distribution in European countries, in the United States. Most likely, we are talking about the strain BA.2.

In Moscow, almost all coronavirus restrictions were lifted in mid-March, and from the beginning of June, the city authorities began to compensate for fines for non-compliance with these measures earlier. The last, fifth wave of COVID-19 in Russia was in mid-February - the maximum rate was recorded in the middle of the month. Then over 200 thousand people became infected per day. After the incidence curve gradually decreased. For the second week, this figure fluctuates in the range of 3.5-4 thousand per day.