One case of Delta COVID subvariant AY.4.2 detected in Singapore: MOH

A woman takes her antigen rapid test under supervision at a Quick Test Centre during the coronavirus disease (COVID-19) outbreak, in Singapore September 28, 2021. REUTERS/Edgar Su
A woman takes her antigen rapid test under supervision at a quick test centre during the coronavirus disease outbreak in Singapore on 28 September, 2021. (PHOTO: Reuters)

SINGAPORE — Singapore has recorded at least one case of a Delta coronavirus subvariant, believed to be more contagious than the dominant strain currently circulating here.

In response to media queries by Yahoo News Singapore, the Ministry of Health (MOH) confirmed that one imported case was infected with the subvariant, also known as AY.4.2, but added that there is no evidence of spread to the community.

"While its effects are still being studied, AY.4.2 is currently expected to be similar to other Delta subvariants in terms of transmissibility and severity of illness," said the MOH in its reply on Thursday (28 October) night.

The ministry did not elaborate on the case's current status or when it was detected.

According to data aggregator site, one case with the AY.4.2 subvariant, yet to be considered a "variant of concern", was detected in the city-state on 8 September.

The site extrapolates information from the Global Initiative on Sharing All Influenza Data (GISAID), the world's largest database of novel coronavirus genome sequences.

Deputy director of Taiwan Centers for Disease Control Luo Yi-jun had also made reference to the subvariant being present in Singapore during a press conference, according to a Central News Agency article published on 22 October.


UK authorities said last week that it was monitoring the subvariant, which makes up 6 per cent of all analysed COVID-19 cases in the country for the week beginning 27 September and is “on an increasing trajectory”.

Around 22,000 such cases have been detected in the UK and some 40 other countries, according to A number of isolated cases of the subvariant have been detected in Russia, Israel, and the US.

UK and Russian experts have said the AY.4.2 may be some 10 per cent more infectious than the original Delta variant, the main driver behind COVID-19 surges across the world, and could ultimately replace it.

But there is no evidence yet that it has caused more severe disease or rendered vaccines ineffective. The AY.4.2 has two mutations in its spike protein, which helps the coronavirus to invade the body’s cells.

These changes have also been seen in other variants but have not gone very far, said Francois Balloux, director of the Genetics Institute at University College London, in a Reuters report.

India's health minister said on Tuesday that a government panel of experts would be looking into the subvariant.

The World Health Organization is currently tracking 20 variations of the Delta variant. Since May, the variant has become the dominant strain circulating in Singapore.

On Wednesday, the MOH confirmed a record 5,324 new COVID-19 cases in Singapore, bringing the country's total case count to 184,419. Of the single-day record high, the ministry said that it is monitoring the "unusual surge" in cases within a relatively short window.

A total of 349 people have succumbed to the disease in the city-state, including 248 who have died this month.

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