COVID-19 cases are once again on the rise in the United Kingdom, and two new subvariants of the dominant omicron variant are spreading fear that the worst is yet to come.

The new subvariants — labeled BA.4 and BA.5 — are not only driving the surge in cases, they are also posing a threat to many since they appear to be capable of partially dodging antibodies from vaccination or past infection.

Because they can dodge immunity, the subvariants can also outpace the previous variants of SARS-CoV-2 in terms of transmissibility. This means they can spread more rapidly than the earlier forms of the virus, as per The Daily Beast.

Another factor that sets the subvariants apart from the parent strain is how they tend to target the lungs. On the other hand, the omicron variant was found to target the upper respiratory tract, resulting in a less dangerous infection.

With the rising cases in the United Kingdom, the United States and other countries are expected to follow suit once the subvariants reach their regions. Interestingly, medical experts are not very worried about the BA.4 and BA.5 strains after looking at the hospitalization and death rates reported in the U.K. amid their spread.

According to preliminary numbers, hospitalizations and deaths due to the new subvariants are increasing more slowly and even declining. This suggests that the strains may not be causing a more severe form of the COVID-19 infection.

“This could mean higher transmissible variants, BA.4 or 5, are in play, [and] these variants are much less severe,” said Edwin Michael, an epidemiologist at the Center for Global Health Infectious Disease Research at the University of South Florida.

Due to the mutated spike protein, the BA.4 and BA.5 strains could be more transmissible. But this does not mean that they would lead to more deaths. Despite their unusual qualities, the two are deemed less dangerous than the previous variants.

University of Alaska-Anchorage virologist and public health expert Eric Bortz told The Daily Beast that the new strains are “immune-evasive enough to infect, but generally not evasive enough to counteract acquired immunity from vaccines and/or prior infection.”

However, it is worth noting that immunity varies from country to country or community to community. Some places may be heavily affected by the subvariants if they have not built stronger immunity over the past years since the pandemic started.

Recorded figures in the U.K. may not reflect what other countries should expect from BA.4 and BA.5. About 87% of their population is fully vaccinated, and 68% is boosted. Although the antibodies developed through vaccination may not prevent breakthrough infections, they help hamper serious infections from happening.