WHO: There may never be a 'silver bullet' to defeat coronavirus

The World Health Organization has warned that, despite strong hopes for a vaccine, there might never be a "silver bullet" for Covid-19, and the road to normality would be long.

More than 18.14 million people around the world are reported to have been infected with the disease and 688,080 have died, according to a Reuters tally, with some nations that thought they were over the worst experiencing a resurgence.

WHO Director-General Tedros Adhanom Ghebreyesus and WHO emergencies head Mike Ryan exhorted all nations on Monday to rigorously enforce health measures such as mask-wearing, social distancing, hand-washing and testing.

"The message to people and governments is clear: 'Do it all'," Tedros told a virtual news briefing from the UN body's headquarters in Geneva. He said face masks should become a symbol of solidarity round the world.

"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."

Ryan said countries with high transmission rates, including Brazil and India, needed to brace for a big battle: "The way out is long and requires a sustained commitment."

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Probe into origins of virus 

The WHO's mission in China laying the groundwork for an investigation into the animal origins of the coronavirus pandemic has concluded, Tedros said.

"The WHO advance team that travelled to China has now concluded their mission to lay the groundwork for further joint efforts to identify the virus origins, he said, adding: "Epidemiological studies will begin in Wuhan to identify the potential source of infection of the early cases."

International hunt

The WHO head said that, while the coronavirus was the biggest global health emergency since the early 20th century, the international hunt for a vaccine was also historic.

"There are many vaccines under trial, a couple in the final stage of clinical trials - and there is hope. It does not mean that we will have the vaccine, but at least the speed with which we reached the level we reached now is unprecedented," he said.

"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. But until we finish the clinical trials, we will not know." 

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