Omicron subvariant linked to higher transmissibility; boosters retain efficacy
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The U.K. health authorities have found that COVID-19 booster shots remain effective against a subvariant of the Omicron variant called BA.2, which is believed to spread faster than the original variant, according to early studies.
On Friday, the U.K. Health Security Agency (UKHSA) cited data from contact tracing from Dec. 27 to Jan. 11 to indicate that the new variant spreads faster in households, with a rate of transmission at 13.4%, compared to 10.3% for Omicron.
According to preliminary findings, COVID-19 booster shots raised the protection against the sub-lineage, with vaccine effectiveness at 70% two weeks following a booster, compared to 13% of effectiveness after 25 weeks or more from the second dose.
âThese early findings should be interpreted with caution as transmission data and dynamics can fluctuate, meaning that early findings can change quickly when new variants are identified,â the agency said.
âWe now know that BA.2 has an increased growth rate which can be seen in all regions in England,â Dr. Susan Hopkins, Chief Medical Advisor for UKHSA, noted.
The UKHSA has detected 1,072 confirmed cases of BA.2, which is believed to have spread across more than 50 countries, including the U.S. On Jan. 27, the New York State Health Department reported its first confirmed cases of BA.2.
In Germany, Health Minister Karl Lauterbach said Friday that the new subvariant could push back the peak of the countryâs current Omicron wave, which was expected to recede by late February.
This week, COVID-19 vaccine makers, Pfizer (NYSE:PFE)/BioNTech (NASDAQ:BNTX) and Moderna (NASDAQ:MRNA), announced the launch of their trials for Omicron-specific shots.
Other leading vaccine makers, Johnson & Johnson (NYSE:JNJ) and AstraZeneca (NASDAQ:AZN), have pledged to develop vaccines specifically targeted at the variant.
However, the race to develop Omicron-specific shots could be premature, according to some U.S. health officials.