New variants of the omicron strain of the coronavirus, which spread much faster than previous strains, are causing a new wave of infections around the world, while vaccine manufacturers are racing with the evolution of the virus to produce modified vaccines that provide protection against the latest forms of the virus, the world media reports. Radio Free Europe.
BA.4 and BA.5
Two new sub-variants of the micron strain of the coronavirus that are spreading rapidly are causing new waves of infections around the world, the BBC points out.
Health experts say the BA.4 and BA.5 subvariants, which were first identified in South Africa, could soon become the dominant strains in Europe and the United States of America (US), after earlier strains of the coronavirus, such as alpha and delta , caused huge waves of infections.
The last subvariants that are causing concern to experts are closely related to the omicron strain that triggered the spike in infections last winter. They were added to the World Health Organization (WHO) monitoring list in March and have also been flagged as variants of concern in Europe.
BA.4 and BA.5 were first reported in South Africa at the beginning of the year and now appear to be spreading much faster than other variants of the coronavirus, according to the British public service, adding that they exist in most European countries and are likely to overtake other types of coronavirus soon. which has already happened in Portugal where BA is dominant.5.
In the US, officials say they are seeing an increasing number of infections caused by these new subvariants. UK coronavirus infections are also on the rise, fueled by BA.4 and BA.5, while Australia has also reported an increase in the number of infections.
Although BA.4 and BA.5 are not thought to be more deadly than other strains of the coronavirus, those subvariants spread more easily, partly because immunity can decline, partly because of the mutations the virus has gone through, but also because many countries have abolished their restrictions for COVID-19 so people are more in contact, which gives the virus more chances to spread.
Masters of immunity evasion
The latest variants are masters at evading immunity, meaning previous infections and vaccines are unlikely to provide much protection against infection, the Guardian points out, noting that BA.4 and BA.5 are more infectious than previous strains and subvariants of the coronavirus, which is why further increases are expected number of infection cases.
The Omicron strain started with three sub-variants – as a group of viruses from the same parent virus – that all appeared in late November 2021 in South Africa: BA.1, BA.2 and BA.3. Although the three sub-variants are genetically distinct enough to have their own Greek names, for some reason this did not happen and the WHO designated them as omicron strain sub-variants.
BA.1, for example, quickly overtook the delta strain in Australia in early January this year, forming a large wave of infections peaking at more than 100.000 per day. BA.2 is more easily transmitted than BA.1, so in early April Australia recorded a second wave caused by BA.2 with more than 60.000 cases per day.
BA.4 was first discovered in January 2022 in South Africa, while BA.5 was discovered in February 2022 also in that country. Both appear to be offshoots of BA.2 and share many mutations, but also have many additional mutations that are likely to affect transmission.
Data from South Africa and Great Britain suggest that the wave of BA.4 and BA.5 infections did not lead to a major increase in severe disease and deaths, which is probably due to the high rate of immunity from previous infections, while in some countries the high rate of immunity over the vaccine could have a similar protective effect.
Each new subvariant of the omicron strain more easily evades immunity from vaccination, according to the Guardian. Current vaccines based on the strain that first appeared in the Chinese city of Wuhan still provide some protection against more serious illness and death from infection with the BA.4 and BA.5 subvariants, but are unlikely to provide much, if any, protection against infections or symptomatic diseases.
Race with the evolution of viruses
The US government has approved new vaccines to protect against the latest strains of the omicron strain, but those vaccines won't arrive until fall, when the number of infected people is already on the rise, the New York Times writes.
While BA.4 and BA.5 are causing a new wave of infections in the US, Great Britain, France, Portugal, Belgium, Israel and other countries, many scientists say that adapting vaccines to new sub-variants is becoming more urgent every day, the paper points out, pointing out that in In the US, the number of deaths from COVID-19, after being at the lowest levels since the beginning of the pandemic for months, is on the rise again.
Many scientists believe that adjusting booster doses will be critical to diversifying human immune defenses because sub-variants bypass the protection offered by existing vaccines. They say keeping up with a virus that mutates so quickly may be impossible, but it's far better to be a few months behind than a few years behind.
Now the question is whether these modified booster doses will arrive on time, underlines the New York Times and indicates that the US Food and Drug Administration (FDA) in an attempt to compete with the latest forms of the virus, asked vaccine manufacturers to adapt the new injections to the BA.4 subvariants. and BA.5, not the original version of the omicron strain from last winter.
Virologists said the subvariant vaccine would create not only the strongest immune defense against current versions of the virus, but also the kind of broad antibody response that will help protect against new forms of the virus that may emerge in the coming months.
However, the New York Times points out, focusing the fall vaccination campaign on the last stage of the virus's evolution may come at a price. Pfizer and Moderna stated that they cannot deliver vaccines adapted to the BA.4 and BA.5 subvariants before October, while experts warn that the process could be further slowed down. On the other hand, the vaccine intended for the original version of omicron is closer - both Moderna and Pfizer have started to make it, with the possibility of delivery during the summer.
Whether the benefits of these newer vaccines, which are not adapted to the latest sub-variants, outweigh the disadvantages of a longer wait depends on exactly when they arrive and how much damage the virus will do before then, the scientists say, stressing that in any case it is crucial that some form of improved vaccine be available until fall.
Returning the measures, at least some?
The biggest public health crisis in this generation, and according to some estimates since the Spanish flu pandemic of 1918-20, is not over, as the number of infected people is on the rise again, the Times points out in an editorial comment.
Because the omicron subvariants BA.4 and BA.5 are more effective than the first strains of COVID-19 at evading natural vaccine-enhanced defense mechanisms, infection rates are likely to increase in the fall and winter months as people spend more time indoors.
However, the conservative British newspaper points out, now is not an emergency situation like when, after the emergence of the new coronavirus at the end of 2019, quarantines were introduced throughout the developed world, but there is still a threat to public well-being and a challenge to health care.
Draconian restrictions along the lines of 2020, the Times says, are not necessary, but moderate measures to stop the spread of the infection, including re-wearing masks on public transport and social distancing, would be reasonable.
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