YOUth should know: New COVID-19 subvariants BQ.1, BQ.1.1

Another pair of subvariants has made its way to Singapore in the perennial pandemic.

On Oct 23, Singapore confirmed four cases of the BQ.1 and BQ1.1 subvariants, all of whom were imported infections.

First detected in Nigeria in mid-July, the two variants, BQ.1 and closely related BQ.1.1, are known to have descended from the Omicron’s BA.5 subvariant.

The Ministry of Health (MOH) stated that while the number of BQ.1 and BQ.1.1 cases have been rising in parts of Europe and North America, they only account for a small proportion of COVID-19 cases globally.

The BQ.1 subvariant is known to have a global prevalence of 6 per cent.

The World Health Organisation (WHO) said that the BQ.1 subvariant has been detected in 65 countries and carries spike mutations in some key antigenic sites while BQ.1.1 has an additional spike mutation at a key antigenic site.

Dr Eric Topol, founder of the Scripps Research Translational Institute, mentioned that while both have mutations relative to BA.5, BQ.1.1 is “riddled with troublesome mutations” that could pose a threat to our immune system’s response.

Carriers of the BQ.1 and BQ.1.1 subvariants may experience cough, fatigue, shortness of breath, sore throat, nausea or vomiting, diarrhea, muscle or body aches, loss of taste or smell, and fever.

The US Centers for Disease Control and Prevention described these strains as the “most evasive yet” as they have the ability to resist existing monoclonal antibody drugs and experts are hopeful that the bivalent omicron boosters will offer protection against the subvariants.

WHO suggested that BQ.1 and BQ.1.1 warrants close monitoring as the additional mutations have conferred an immune escape advantage as compared to other circulating Omicron sublineages.

However, the XBB variant continues to be the predominant subvariant in Singapore, accounting for 60 per cent of of all new cases as of Oct 14.

MOH added that it is closely monitoring the prevalence of circulating variants within the community.