According to a federal official interviewed by The New York Times, 100 million Americans could contract COVID-19 this fall and winter, spurred by indoor gatherings and weakened immunity. While that’s less than the number of people affected by the Omikron virus last winter, the estimate (based on unspecified models, The New York Times reported) found that the Omikron family strain could cause about 30 percent of U.S. The population is infected.
According to a May 5 report from the U.S. Centers for Disease Control and Prevention (CDC), Omicron and all its forms are currently causing 100 percent of COVID-19 cases in the United States. According to the CDC, there are several subtype strains of Omicron, but BA.2 (originally called “Invisible Omicron”) and BA.2.12.1 make up the majority of COVID-19 cases in the United States. (BA.1 is the “primitive” Omicron that caused the winter surge in cases).
As of May 4, cases were up about 21% compared to the previous seven-day average, the CDC said. Hospitalizations also rose by about 17 percent. Dr. Eric Topol, director of the Scripps Research Translational Institute, tweeted that the current “rise rate” is similar to last summer’s delta variant growth, while still remaining relatively low.
A CDC report recently confirmed that as of February 2022, nearly 60% of Americans and as many as 75% of children were infected with COVID-19. The researchers looked at infection-induced antibodies, which are distinct from vaccine-induced antibodies, Kristie Clarke, Ph.D., researcher on the study, said in a media release. She also said that prior infection does not necessarily equate to immunity to COVID-19, because the researchers did not measure levels of protective antibodies against reinfection with COVID-19 or severe disease.
Here’s what you need to know about BA.2 and other versions of Omicron:
What is a subtype strain or sublineage?
Variants are composed of multiple lineages and sub-lineages. According to the CDC, each variant has a “paternal line” followed by other lines, which you can think of as a family tree. As the virus spreads from person to person, mutations occur, but not all of the mutations change the properties of the virus in a meaningful way.
The Omicron variant and its sublineages make the virus more contagious and able to infect more people, but it causes, on average, less severe disease than the delta variant.
Genome surveillance can uncover variants and sub-lineages. Scientists in South Africa were able to quickly identify last winter that Omicron was a new variant because of the way it was presented by PCR testing. The original Omicron produces a falling signal or marker in testing to differentiate it from the Delta, which was the previous dominant variant of the Omicron. However, BA.2 did not have the same signal, known as S gene target failure. This makes it more stealthy, although genome sequencing (which happens with about 10% of COVID-19 PCR tests in the U.S.) will detect all Omicron sub-variants and coronavirus variants in general.
What are the symptoms of the current COVID variant?
Currently available data suggest that BA.2 does not cause more severe disease than the original Omicron variant, even though it is more transmissible. (WHO notes that the difference in transmission between the original Omicron and the Invisible Omicron is smaller than the difference between Delta and Omicron).
No studies have yet shown that BA.2 causes different symptoms than the original Omicron variant. For many people infected with COVID-19 (especially those who are fully vaccinated or boosted), COVID-19 symptoms are similar to cold symptoms, such as sore throat, runny nose, and fatigue.
Is BA.2.12.1 more serious? Will vaccines work?
Taking into account all available real-world data, WHO concluded that, despite the growth advantage of the latter, there was no reported difference in severity between Omicron BA.1 and BA.2.
Between BA.2 and BA.2.12.1, the newer version is considered to be about 25 percent transmissible, but more evaluation and research is underway, CDC Director Dr. Rochelle Walensky said in a media briefing. .
Like the original Omicron, BA.2 means that more fully vaccinated people will experience breakthrough infections. But those who were fully vaccinated, particularly the booster vaccine against COVID-19, “continue to have strong protection against severe disease,” Walensky said at the briefing.
In a statement on March 8, the WHO said that although some people have been infected with BA.2 after already contracting COVID-19, which is caused by Omicron, early data suggest that infection with BA.1 Provides “substantial protection” to BA.2, at least for a while.