World may have to face a mutant virus with ineffective vaccines

People must be prepared for the coronavirus to mutate into a more virulent strain or for the possibility that new vaccines will prove ineffective, a leading former World Health Organisation scientist said.

The only way the world can combat the virus effectively is through stringent track-andtrace measures that will lead to local lockdowns, Prof David Heymann told The National.

As a ribonucleic acid virus, Covid-19 could change and become deadlier, he said. “These viruses are not stable and might mutate in such a way to become less severe or more severe, or more transferable. It’s very difficult to say.”

Prof Heymann is one of the world’s most experienced infectious disease specialists having dealt with Ebola outbreaks in Africa in the 1970s and Sars in 2003 with the WHO. He is currently a distinguished fellow in Global Health Programme at the Chatham House think tank.

While hopes are high for a vaccine in the coming months, Prof Heymann said people had to be prepared that it might not be ready for a year or be 100 per cent effective.

“It’s not a done job when a vaccine is licensed, that’s just the beginning. We won’t know how long immunity lasts – it might just be six months. It also depends on how many booster doses need to be given,” he said. “We don’t even know if it will be effective in the short term and we don’t know when it will be ready.”

With many European countries now adopting localised lockdowns – Britain in recent weeks shut down Manchester, Preston, Leicester and

Aberdeen – Prof Heymann believes this will be the template for containing Covid-19. “It’s about finding where a transmission is occurring and it’s about interrupting that transmission from the source. Once Covid is interrupted you can open up again.”

With more than 20 million people infected and substantial rises in Africa and the American continents, he believes Covid-19 is spreading westward from China. But the mortality rate was still significantly lower than many other diseases, he said.

Prof Heymann said the death rate in the Middle East was low because sensible precautions were taken, while reducing the Hajj was also effective in slowing the spread. “The Middle East has always been very careful in taking precautions after cholera and meningitis outbreaks in ... the Eighties.”