Public health officials have warned of an “alarming” spread of false rumours about the Covid-19 epidemic, and planning is under way to deal with any infection epidemic in Western countries (see story below).

Two weeks ago Indian researchers published a genetics paper that claimed to have found unusual insertions in the genome of the virus sweeping China. Some were similar to those in HIV.

The suggestion was that these mutations could not have arisen naturally and were instead inserted at a laboratory.

The allegation has become one part of what the World Health Organisation has referred to as an “infodemic” of misinformation, which includes claims that the virus was spread in poison clouds or transmitted by pets, or that it spread to humans from people eating bat soup.

The idea that it was engineered, though, perhaps as part of a weaponisation program, has been particularly persistent because it is traced to a genuine research paper. Published by scientists from a Delhi research institute, it was titled “Uncanny similarity of unique inserts in the 2019-nCoV spike protein to HIV-1 gp120 and Gag”. It claimed that the “inserts” were “unlikely to be fortuitous in nature”.

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The paper has since been withdrawn from the preprint server Biorxiv. Trevor Bedford, from the Fred Hutchinson Cancer Research Centre in Seattle, said that it should not have been published.

“If you look there’s no evidence of genetic engineering. The mutations we have are completely consistent with natural evolution,” he told the annual meeting of the American Association for the Advancement of Science in Seattle.

The work looked at the genome of Sars, a similar coronavirus that caused an epidemic in 2002, and analysed regions where the two differed, finding a link to HIV.

“This was wrong on a number of different levels,” Professor Bedford said. “Those sequences were not unique. They are not inserts, they are just natural.” He said that they could be found throughout nature.

There are also thousands of differences, making it hard to sustain the idea that the Sars virus had simply been tweaked to make it more potent. “If you’re engineering something, you wouldn’t do that.”

This week the World Health Organisation called on technology companies to crack down on harmful rumours. Andrew Pattison, WHO’s digital business solutions manager, said that incorrect information was “spreading faster than the virus”.

Half of Britons would fall ill in a worst-case virus outbreak

The UK government is working on the assumption that half of Britons will be infected with coronavirus if China cannot bring it under control soon.

Contingency planning envisions that if Covid-19 spreads unchecked it will reach every part of Britain within a few months. A “reasonable worst case” scenario anticipates hundreds of thousands of deaths and intensive care units forced to make “hard choices” about prioritising people.

However, even in the worst pandemic only 1 per cent to 4 per cent of those infected would need hospital treatment. Most people would get better by staying at home and using over-the-counter remedies.

Health chiefs are relying on the summer to mitigate an outbreak in Britain, and hope that Chinese efforts will delay the spread until the weather warms up. They hope that coronavirus will behave like flu, which spreads far more slowly during the summer, buying time to develop a vaccine in case it returns next winter.

“Sunlight kills viruses quickly. Sars pretty much died in July and August [2003] and it’s quite plausible we’ll see that here,” Paul Hunter, of the University of East Anglia, said.

“In summer schools are closed and people are also out of doors more. If you’re walking around in the sunshine you are much less likely to spread infection than if you’re cramped up together to keep warm indoors.”

About half a billion people in China are under some form of travel restriction as Beijing tries to contain the outbreak within Hubei province, where it began at the end of last year.

So far about 52,000 of the more than 64,000 global cases have been in the central Chinese province, and British officials believe that it will become clear in the next few weeks whether there will be a serious outbreak in other big cities leading to uncontrolled global spread.

There has been concern about the eight confirmed cases in Britain but there is little risk that they will lead to an outbreak as the patients’ contacts are systematically isolated. Chris Whitty, the chief medical officer, has said that Britain will be at real risk of an outbreak only if the virus spreads out of control in southeast Asia.

“What we are seeing are the droplets before the wave,” a government source said.

Planning has started for such an outbreak, however, and Public Health England has briefed the emergency services that the virus would quickly spread across the country.

The government is working on a “contain, delay and mitigate” strategy that relies on helping China and other Asian governments, preparing the National Health Service and advising people to use tissues and self-isolate if they are ill.

Accepting that symptoms would vary in severity, a Whitehall source said: “We are working on the basis that half the population are impacted in some way.”

Contingency planning is based on the Department of Health’s 2011 flu pandemic strategy, which envisioned half the population taking time off work. The plan said that there was no point in closing the border because modelling suggested that even halting 90 per cent of inbound flights would slow a pandemic by only two weeks.

In a serious outbreak, hospitals will have to cancel all non-emergency work to cope with extra patients. However, the plan accepts that critical care services cannot be expanded indefinitely and that “it may be necessary to prioritise access to some services in an ethically appropriate way”.

Undertakers may need help to cope with the number of extra deaths, the plan says. So far 2 per cent of those known to have had the coronavirus have died, but there is hope that the true mortality rate will be lower as those with very mild symptoms have not been counted in official figures.

Only about 30 per cent of those infected would need help from GP surgeries or NHS 111, the plan says, adding that “staying at home, keeping warm, drinking plenty of fluids and the use of over-the-counter cold and flu medicines should be sufficient to meet the needs of most patients”.

There is no plan to close schools, but the strategy accepts that some will be forced to shut because so many of their teachers will get sick. Offices may have to accept staff working at home.

However, the plan does not involve cancelling sporting events or concerts, saying: “Large public gatherings or crowded events where people may be in close proximity are an important indicator of ‘normality’ and may help maintain public morale.”

Although the government is confident that people will not go hungry it envisions a “reduction in choice and accessibility” of food as shops are forced to shut.

Some civil disorder is foreseen, but the emergency services are warned that they cannot rely on the military to step in as “their own personnel will be equally vulnerable to illness, they may have little or no spare resource”.

The Times