Why these are very risky times to be taking our first major step towards 'living with Covid'

Given what the world has been through in the past 18 months it's almost impossible to imagine anything like a normal life alongside Covid-19.Ask a scientist, however, and they might tell you the story of a little-known virus called OC43. It's believed to have first emerged in around 1890 when it jumped from mice into cattle and then humans.

It's now believed to have been responsible for the "Russian flu" pandemic originating in central Asia.

It spread around the world in three successive waves that killed an estimated two million people. 

One of the reasons you've never heard of OC43 is that by the time it became recognised as a coronavirus in the 1960s it wasn't much of a problem. 

It was only dangerous to the very frail, and one of a group of four "seasonal" coronaviruses that cause between 20-30% of common colds. 

Most of us have some level of immunity to it, particularly children who are exposed to it several times every winter as waves of infection spread around the world. 

Seasonal coronaviruses like OC43 mutate into different variants over time, but there appears to be sufficient similarity between them from one year to the next to prevent a repeat of the pandemic they unleashed when they first infected humans.

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There's every reason to expect the story of SARS-CoV-2 ( the coronavirus that causes Covid-19 ) to be similar.

It will gradually infect more and more people, mutating as it goes. And, through a combination of vaccines and natural infection, the virus and its human host will eventually find a way to grudgingly coexist.If that's the case, why worry about lifting resections on July 19?

Let's take off those masks and do what Sajid Javid suggests: "Learn to accept the existence of Covid and find ways to cope with it." 

As the health secretary points out, we "accept" the flu.

We're happy to live side-by-side with measles, diphtheria, rubella. The only problem is we're still a long way from an even slightly healthy relationship with Covid-19. The first issue is immunity.

Even once every adult in the UK is vaccinated, we'll be a long way from "herd immunity" needed to prevent the virus from spreading. 

To achieve that, we'd need to vaccinate all of the UK's children as well. But current expert opinion is that that can't happen until all the adults have had their vaccines first and there's more data on vaccine safety in kids.

Some experts believe it's unethical and unwise to vaccinate our children until adults around the world have been vaccinated first (more on this later).

The second is the vaccines themselves.

The reason we can "accept" living with viruses like measles, diphtheria, rubella and can thankfully forget about smallpox and polio is because the vaccines prevent these diseases.

While our Covid vaccines are brilliant and will save millions of lives worldwide, they don't prevent Covid. They're just preventing people from dying from it."Vaccines are currently being used to prevent illness in people, rather than the usual primary aims of a vaccine which is to prevent infection in the first place," says Richard Tedder, a virologist at Imperial College London.While that's a whole lot better than nothing, it's a problem when viruses like SARS-CoV-2 are rapidly mutating to adapt to their new host. Yes, we're talking about new variants.

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It's very likely the Delta variant won't be the last version of Covid-19 that evolves. The virus has only been infecting humans for a year-and-a-half and as one scientist put it to me: "We're already halfway through the Greek alphabet." Given the likely emergence of new variants, many experts worry that even if we vaccinate the entire population of the UK, including children, and drive down rates of infection to practically zero, if Covid-19 is still at large globally, it's only a matter of time before variants return (perhaps with vengeance).The government's decision to remove all coronavirus restrictions in England, likely on July 19 is not, and arguably should not, be based solely on how the Covid-19 epidemic will respond.

The impact on the economy, the vast backlog of NHS operations, the nation's mental health are all enormous considerations. But we can't ignore the reality of where we are right now.

Cases are doubling every nine days.

Within a couple of weeks cases will likely be comparable to where they were at the height of the winter peak.

It's very likely vaccines will keep deaths at a fraction of what they were back then. 

But these are very risky times to be taking our first major step towards "living with Covid-19". 

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