A new omicron subvariant of the virus that causes COVID-19, BA.2, is quickly becoming the predominant source of infections amid rising cases around the world. A new article in the Ventura County Star provided a closer look at what makes it different from previous variants, whether there will be another surge in the U.S. and how best to prepare.

BA.2 is the latest subvariant of omicron, the dominant strain of the SARS-CoV-2 virus that causes COVID-19. While the origin of BA.2 is still unclear, it has quickly become the dominant strain in many countries, including India, Denmark and South Africa. It is continuing to spread in Europe, Asia and many parts of the world.

The omicron variant has three main subvariants in its lineage: BA.1, BA.2 and BA.3. The earliest omicron subvariant to be detected, BA.1, was first reported in November 2021 in South Africa. While scientists believe that all the subvariants may have emerged around the same time, BA.1 was predominantly responsible for the winter surge of infections in the Northern Hemisphere in 2021.

Some scientists have called BA.2 a “stealth” variant because, unlike the BA.1 variant, it lacks a particular genetic signature that distinguishes it from the delta variant. While standard PCR tests are still able to detect the BA.2 variant, they might not be able to tell it apart from the delta variant.

BA.2 is considered to be more transmissible but not more virulant than BA.1. This means that while BA.2 can spread faster than BA.1, it might not make people sicker.

A recent preliminary study that has not yet been peer reviewed of over 1 million individuals in Qatar suggests that two doses of either the Pfizer-BioNTech or Moderna COVID-19 vaccines protect against symptomatic infection from BA.1 and BA.2 for several months before waning to around 10%. A booster shot, however, was able to elevate protection again close to original levels.

Importantly, both vaccines were 70% to 80% effective at preventing hospitalization or death, and this effectiveness increased to over 90% after a booster dose.

CDC data suggests that BA.2 cases are rising steadily, making up 23% of all cases in the U.S. as of early March. Scientists are still debating whether BA.2 will cause another surge in the U.S.

Though there may be an uptick of BA.2 infections in the coming months, protective immunity from vaccination or previous infection provides defense against severe disease. This may make it less likely that BA.2 will cause a significant increase in hospitalization and deaths.

The U.S., however, lags behind other countries when it comes to vaccination, and falls even further behind on boosters.

Whether there will be another devastating surge depends on how many people are vaccinated or have been previously infected with BA.1. It’s safer to generate immunity from a vaccine, however, than from getting an infection.