SINGAPORE - With Singapore experiencing a spike in Covid-19 community infections that were largely driven by newer Omicron variants as well as fears of a new wave, ST answers some questions on what you need to know to be prepared.
On the Omicron new variants - BA.4 and BA.5.
Q: Why are there so many Omicron sub-variants?
A: Omicron has spread rapidly and this has given it many opportunities to mutate and also acquire specific mutations of its own.
Some of these sub-variants include BA.1, BA.2, BA.3, BA.4 and BA.5.
There have been sub-variants of earlier versions of the virus, such as the Delta variant. However, Omicron has overtaken these, most likely due to its increased transmissibility.
Q: Should we be worried?
A: Currently, international and local evidence show that the severity of BA.4 and BA.5 infections is similar to that of earlier Omicron strains.
Experts have also noted that it will evolve constantly so the process of discovering new variants will continue even after Covid-19 becomes truly endemic.
A recent study also noted that people infected with the earliest version of the Omicron variant may be vulnerable to reinfection with later versions even if they have been vaccinated and boosted. The study said that newer sub-lineages "notably evade the neutralising antibodies elicited by Sars-CoV-2 infection and vaccination" the researchers found in test-tube experiments.
Q: Are these new strains dominant here?
A: Singapore has witnessed a 23 per cent week-on-week increase in Covid-19 community infections, with the rise largely ...