Respected Thai virologist, Prof. Dr. Yong Poovorawan, of Chulalongkorn University, has predicted that the Delta (Indian) variant of COVID-19 will replace the Alpha (UK) variant as the dominant strain around the world in the next 4-5 months, because it is 1.4 times more transmissible than the Alpha strain.
He also said, however, that the severity of the symptoms caused by the two variants are not that different, but the mutated virus has an impact on the efficacy of vaccines produced from the original virus strain from Wuhan in China.
To cope more efficiently with the variants, Dr. Yong stressed the need for the development of a second generation of vaccines, which several pharmaceutical companies are now doing and which will take at least six months to roll out.
Regarding the Beta (South African) variant, Dr. Yong said that it has been found in Thailand, but the infections are more limited than the Delta strain infections.
He cited a study on the impact of the Delta variant on vaccines in Scotland, which shows that the efficacy of both Pfizer and AstraZeneca dropped by about 10%.
In the case of Thailand, he said a study is underway to determine whether third booster vaccine jabs are necessary, noting that safety concerns must come first and that the study on mixed vaccine use, which is currently underway, will have to be completed first and assessed, before there is a change of vaccine policy in Thailand.
The best defence against the onset of the Delta variant in Thailand is to delay the spread of the strain, he said.
Commenting on the government’s plan to reopen Thailand to fully vaccinated foreign arrivals from low-risk countries in the next 120 days, Dr. Yong said that, if there are still thousands of new infections each day in Thailand by then, foreign tourists will not visit Thailand anyway, so full cooperation is urged from everyone to contain the pandemic.
