BA.4 and BA.5 are subvariants of the omicron omicron. The United States continues to see a rise in interest in omicron subvariants BA.4 and BA.5.
According to a Tuesday update from the Centers for Disease Control and Prevention, BA.4 was responsible for 5.4 percent of all new cases in the country for the week ended June 4.
Since April, the subvariants have slowly been spreading to the U.S.
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According to Dr. Ashish Jha, White House Covid-19 coordinator, BA.4 or BA.5 will be the dominant U.S. currency by the end of this summer or early fall.
Omicron and its variants have been spreading fast. On December 1, the first case of omicron in the United States was discovered. This virus, now known as BA.1.1, was quickly overtaken by the delta variant.
Since then, many transmissible micron subvariants have been discovered and have taken root: The dominant strain at the moment is BA.2.21.1. This has pushed out BA.2, which in turn has pushed out BA.1.1.
Jha stated that the “very rapid viral development” of the Omicron strain is due to the pathogen trying out the U.S. “wall of immunity”. The virus cannot survive if it is not able to evolve into forms that can evade immunity because a large number of Americans are immune to the virus.
A small laboratory study in South Africa was posted online to a preprint service at the end April. It found that both the BA.4 & BA.5 subvariants were capable of evading antibodies from unvaccinated and vaccinated individuals, but the antibodies from vaccinated people did better.
BA.2.21.1 is still the most popular variant in the country. According to the CDC, 62.2 percent of all new cases were due to it as of last week.
The subvariants of omicron have not been shown to cause any more severe diseases than the original omicron strain. Omicron is less likely to cause severe illness than delta but it can still cause significant death because of its transmissibility.
