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COVID-19 Omicron Subvariant BA.2 on the Rise

While coronavirus case numbers have been on the decline in the United States, the highly contagious subvariant of Omicron, BA.2, increased its prominence in Europe, Southeast Asia, and the Western Pacific region, and could similarly surge in the United States.

The World Health Organization called the subvariant the main cause of coronavirus cases worldwide, and “since its takeover, international case counts—which had been declining since the first week of January—have been rising again,” according to CNN.

A laboratory study of BA.2 suggested that the subvariant’s ability to quickly spread is probably due to being more transmissible than BA.1, another Omicron subvariant. “And other preliminary studies suggest that BA.2 can readily overcome immunity from vaccination and previous infection with earlier variants, although it is not much better than BA.1 at doing so,” Nature reported back in February, as BA.2 picked up speed in the Philippines, South Africa, and Denmark. “If real-world epidemiological studies support these conclusions, scientists think that BA.2 will be unlikely to spark a second major wave of infections, hospitalizations, and deaths after Omicron’s initial onslaught.”

Although BA.2 was first discovered in November 2021, the subvariant seemed to hit its stride at the beginning of 2022.

“It’s possible that BA.2’s high transmissibility is driving these increases in cases,” The New York Times reported. “But it’s also hard to disentangle the subvariant’s effects from other factors.” Some of those factors include European nations easing several measures meant to decrease the chance of spreading the virus, and the decrease in immunity for individuals who may have been vaccinated but failed to receive a booster shot.  

By the end of March, the U.S. Centers for Disease Control and Prevention (CDC) found that the BA.2 subvariant accounted for roughly 55 percent of the COVID-19 variants in the United States, Reuters reported. The CDC has monitored shifting trends in coronavirus variants and their prevalence—including a 39 percent increase in new coronavirus infections this week compared to last week—via genomic surveillance, with assistance from commercial or academic labs, as well as state or local public health laboratories.

“The hardest-hit region was the Northeast, where BA.2 caused more than 70 percent of all cases,” CNN reported.  

But U.S. health and medical experts remain unsure on the level of impact that the subvariant might have in the country, “in part because so many people were infected by the original Omicron wave this winter and most likely have at least some natural or vaccine immunity to protect them against severe illness and hospitalization,” according to the Times

On Wednesday, 30 March, U.S. President Joe Biden asked Congress to approve additional financial aid to deal with COVID-19. “On Capitol Hill, senators of both parties said they hoped a deal could be struck before Congress leaves next week for a two-week April recess,” the Times reported. The deal would likely cost more than $15 billion.

Biden got his second booster shot after his speech, which also pointed to a new U.S. coronavirus website,, which went live Wednesday and is meant to help users figure out how to access testing, treatment, vaccines, and masks. It also helps users determine the risk of the virus in their communities, a valuable tool in remaining informed even before health departments issue public warnings. Another resource that provides case tracking on a county level is the CDC’s COVID Data Tracker website

People ages 50 or older are eligible to receive a second booster shot in the United States, which could improve resistance to BA.2. The only other people eligible are those 12 years and older who have certain immune deficiencies. With vaccines and booster shots available, some medical experts, such as Dr. Erica Johnson who spoke with the Associated Press, suggested taking advantage of the current dip in COVID cases.

If you’re on the fence, use this lull to talk with your doctor about how protected you really are—and need to be,” recommended Johnson, an infectious disease specialist at the American Board of Internal Medicine.

The Biden administration also announced that it intends to stop turning away immigrants, which it has been doing since March 2020 in line with a public health order. Under the public health order, border officials can quickly deport undocumented migrants—including ones seeking asylum—in an effort to curb the spread of COVID-19 at border facilities and communities.

In the order, the CDC noted that “the increased movement of typically unvaccinated noncitizens into the United States presents a heightened risk of morbidity and mortality to this population due to the congregate holding facilities at the border and the practical constraints on implementation of mitigation measures in such facilities.”

The agency also listed that most migrants coming to U.S. borders were traveling from countries with “markedly lower vaccination rates,” including Ecuador, El Salvador, Guatemala, Honduras, and Mexico, based on 2021 data.

“In all, there have been 1.7 million expulsions under the order, which was issued by the Centers for Disease Control and Prevention and known as Title 42,” the Times said.

The change in policy is expected to take place in late May.