Q&A

Q: Not all vaccines are 100 per cent effective. If one is about 70 per cent effective, would that be good enough?

PROFESSOR OOI ENG EONG: 70 per cent effectiveness is actually very good. You know, even a natural infection would not give you 100 per cent protection from a second infection.

Whether Covid gives you lifelong protection or short-lived protection, that is something that is being debated… The way the vaccine works is it isn't just at the individual level.

So, the person who falls into the 70 per cent and is protected against infection, that is great, they won't get it. But actually, they go on to protect the others who don't actually develop immunity, and that is this whole concept of herd immunity.

Q: When a vaccine is found, who should get it first?

PROFESSOR DALE FISHER: Once we get a vaccine, we are not going to suddenly get enough for the whole country. So, we might have to discuss: Do we vaccinate older people or those that are immune-suppressed, or do we vaccinate those that are looking after them?

Nearly all the nursing home outbreaks, for example, are a result of a staff member introducing it (the virus). So, this is an important discussion because you might think, let's just vaccinate all the immune-suppressed and the elderly, but that may not be the most rational thing... I would certainly like to vaccinate all the people that work in a nursing home.