SARS-CoV-2 is the third type of Coronavirus to cause severe symptoms after SARS-CoV (2002-3) and MERS-CoV (2012). And now it seems that SARS-CoV-2 is working in threes itself.
Researchers who mapped some of the original spread of coronavirus in humans have discovered there are THREE variants of the virus throughout the world. They reconstructed the early evolutionary paths of COVID-19 as the infection spread from Wuhan, China, out to Europe and North America. Dr Peter Forster, geneticist and lead author from the University of Cambridge, said: ’There are too many rapid mutations to neatly trace a COVID-19 family tree.’
17-18 years after the Sars outbreak and 7-8 years after MERS-CoV, there is still no coronavirus vaccine. Of the 33 vaccine candidates for SARS-CoV, only two reached clinical trials on humans, the rest stopped at the preclinical stage. For MERS-CoV, just three of the 48 vaccine candidates went to clinical trials on humans while the others only made it to the preclinical stage.
WHO director general Tedros Adhanom Ghebreyesus said a vaccine could be available in 18 months.
SARS-CoV-2 is already proving an elusive adversary and is highly likely to mutate further which means one vaccine is unlikely to be enough. Furthermore, there is an additional risk of new types of coronaviruses developing which would point to the development of multiple vaccine candidates which would be deployed in the same way as the annual flu vaccine; rather like flu, the strategy would be about mitigation of hospitalisation and deaths.
As governments ponder how to get the world back to normality, relying on a “magic pill vaccine” does not seem to be an option, at least for 2020.