World Health Organisation head Dr Tedros Adhanom Ghebreyesus said work on an "effective" vaccine is under way in several countries
But a perfect one to end the pandemic may never be found
Sky reports:
- A number of vaccines are now in phase three clinical trials and we all hope to have a number of effective vaccines that can help prevent people from infection.
- However, there's no silver bullet at the moment - and there might never be.
- There are concerns that we may not have a vaccine that may work, or its protection could be for just a few months, not more.
