Warning of two nCoV strains that can cause a new wave of infections

The appearance and increase of BA.4, BA.5 in South Africa and some parts of the world made experts fear that it would cause a new wave of epidemics. Because they can evade immunity.

South Africa is witnessing the emergence of a fifth wave of Covid-19 as the number of new cases spikes again in the country. According to the New York Times, the cause is two sub-lines of Omicron - BA.4 and BA.5.

The BA.4 and BA.5 sublines of the Omicron variant originated in South Africa.

In the last week of April, the number of cases in South Africa tripled. Hospitalization rates have also increased. The increase is concentrated mainly in the provinces of Gauteng, Western Cape and KwaZulu-Natal, occurring just a few months after the Omicron wave appeared in South Africa in winter 2021.

BA.4 and BA.5 are both branches of the original Omicron, first discovered in November 2021. Earlier, WHO also said it was closely monitoring BA.4 and BA.5 because 'they contain additional mutations that need to be studied further to understand its impact on immune escape'.

These two substrains are more contagious than BA.2 and are themselves more contagious than the original Omicron strain. Scientists are still studying whether they make infected people worse.

In the US, health officials have determined that BA.4 and BA.5 are present at low levels, although Omicron's other substreams BA.2 and BA.2.12.1 are predominant. However, according to Fortune, every US state has detected BA.4 or BA.5 infections, predicting the possibility of rapid spread. The earliest samples infected with BA.4 were found in the US on March 30 and BA.5 on March 29.

According to the findings of Professor Alex Sigal, of the African Institute of Health Research, located in South Africa, people who have been infected with Omicron BA.1 but have not been vaccinated have reduced neutralizing antibodies to one-eighth of exposure when exposed. BA.4 and BA.5. Meanwhile, those who have been vaccinated and previously contracted the disease are likely to have only one-third left.

These results surprised Mr. Sigal. The ability to escape the immunity of BA.4 and BA.5 was beyond the expectation of this expert, especially considering its changes to the original Omicron.

Professor Alex Sigal is also the one who warns that two strains BA.4 and BA.5 can cause a new wave of Covid-19 because they have the ability to evade antibodies, even in people who have been vaccinated or have had the disease before. there.

Symptoms in people infected with BA.4 and BA.5 are still quite similar to those infected with the original Omicron strain such as fever, loss of smell, fatigue, and malaise. The person with the disease does not have respiratory failure - a symptom that the disease is getting worse. As a result, experts concluded it was less likely to cause death.