| 1 October 2022, Saturday |

Omicron subvariant BA.2 more infectious than ‘original,’ Danish study finds

According to a Danish study, the BA.2 subvariant of the omicron coronavirus variant, which has swiftly taken over in Denmark, is more transmissible than the more prevalent BA.1 and more capable of infecting vaccinated persons.

The study, which looked at coronavirus infections in over 8,500 Danish homes between December and January, discovered that those infected with the BA.2 subvariant were around 33% more likely to infect others than those infected with the BA.1 subvariant.

The “original” BA.1 subvariant accounts for more than 98 percent of omicron cases worldwide, but in Denmark, its close relative BA.2 has swiftly become the dominant strain, dethroning BA.1 in the second week of January.

“We infer that omicron BA.2 is naturally far more transmissible than BA.1, and that it also has immune-evasive features that further diminish the protective impact of immunization against infection,” the study’s authors said.

Researchers from Statens Serum Institut (SSI), Copenhagen University, Statistics Denmark, and Technical University of Denmark completed the study, which has not yet been peer-reviewed.

“If you have been exposed to Omicron BA.2 in your home, you have a 39% chance of becoming infected within seven days.” If you were instead exposed to BA.1, your chances are 29 percent,” lead study author Frederik Plesner told Reuters.

This implies that BA.2 is approximately 33% more infectious than BA.1.

Cases of BA.2 have also been reported in the United States, the United Kingdom, Sweden, and Norway, albeit to a considerably smaller extent than in Denmark, where it accounts for around 82 percent of cases.

The study also found that BA.2 was considerably better than BA.1 in infecting vaccinated and booster-vaccinated patients, indicating that the subvariant had more “immune evasive qualities.”

Vaccines, however, continued to play an essential role, as both booster-vaccinated and fully vaccinated persons were less likely to become infected and transmit either subvariant when compared to those who had not been vaccinated.

According to preliminary SSI study, there is no change in the probability of hospitalization between BA.2 and BA.1.

According to the UK Health Security Agency, the study also verifies early research from England, which found that BA.2 appears to have a significant growth advantage over BA.1.

  • Reuters