[sgxin]

Should allow Sinovac for the under 18 and Sputnik-V too once WHO approves it.

I don't think Sinovax is very effective against Delta but at least it protects against severe illness. Guangzhou managed to contain it by lockdown and social distancing, not by vacc alone.

Though the antibody level will be lower, I tend to agree with the view that full inactivated virus should produce a wider protection against variants.  
If one desires a higher antibody level, can always go for a 3rd dose of Sinovac where antibody is reported to increase 10-25 times.

And don't agree with the social distancing part as the peak-hour subway is as jam packed as Tokyo.

Sinovac shot seen highly effective in real world Chile
https://www.globaltimes.cn/page/202107/1228213.shtml

A Beijing-based immunologist told the Global Times on Thursday on condition of anonymity that in theory, inactivated vaccines carry all antigens of the virus, so they are able to neutralize a wider coverage of variants. Its efficacy against mutations should be better than the mRNA vaccines, but this requires further evaluation.