Yusuff Adebayo Adebisi knows that a vaccine that offers 70% protection against COVID-19 could be a valuable tool against the coronavirus pandemic in Nigeria — especially if that vaccine is cheap and doesn’t have to be stored at extremely cold temperatures. But what if another vaccine — one that is more expensive to buy and to store — was 95% effective?
“Should we send the less-effective vaccine to Africa? Or should we look for a way to strengthen the cold storage?” asks Adebisi, director for research at African Young Leaders for Global Health, a non-profit organization based in Abuja.
These are the kinds of question facing researchers and government leaders worldwide, as they take stock of the emerging selection of coronavirus vaccines.
Researchers are also starting to test a range of doses, schedules and combinations of vaccines. They still do not know how long vaccine-mediated immunity will last, or how well the various vaccines reduce coronavirus spread — all factors that could shape which is considered the ‘best’. “It’s not just a matter of getting them out as fast as possible,” says [vaccine epidemiologist Mark Jit]. “It’s making sure that as we get them out, we are putting in place the surveillance studies to see how well the vaccines are doing in different situations.”