From 4 July, social distancing rules in England are being eased. People will be encouraged to stay “one-metre plus” away from others, but continue to remain two metres apart whenever possible.

Does that mean that the risk of getting infected with coronavirus as we go about our daily business has gone down?

According to some experts, the answer is no. Sadly, it may have actually gone up.

This is because the number of people infected with coronavirus is remaining relatively stable.

With people able to go to pubs, cafes, restaurants and other venues – at a distance of at least one metre from others – the chances of the average person catching COVID-19 has risen.

Dr Konstantin Blyuss, reader in mathematics at Sussex University and co-creator of a COVID-19 model, told Sky News: “Less than 10% of the country have had the disease, so out of 10 people, nine can still catch it.

“The difference from three months ago is now there are lots more carriers or people just walking with it on the streets – we are opening a possibility for transmission, such as pubs and elsewhere where there are confined and close spaces. It’s a perfect breeding ground.

“So, there is a much higher chance that actually infection will pick up again very quickly.”

Kevin McConway, emeritus professor of applied statistics at the Open University, added: “If somebody… thinks it’s fine for me to go out: if everyone in the area thinks that and one infection comes in, people are meeting many more people than they would otherwise meet if they hadn’t all gone out to the shops and so on, and therefore the risk is actually higher.”

So how do people gauge their own personal degree of risk, when deciding what to do and where to go?

One of the best ways might be to look at the number of infectious people in their areas right now.

Sky News has analysed how many new confirmed cases are currently in lower-tier local authorities to give you a sense of how many there are in your area.

It uses a “two-week rate” – which counts up all the people to have tested positive in each authority area in a 14-day period – because experts say the best way to monitor diseases is to look at changes on weekly or fortnightly basis. This provides a clearer picture of where the disease is accelerating or slowing.

It happens to be around the same period that other experts – and indeed the government’s own advice – say that COVID-19 can remain infectious for two weeks on average.

Catherine Noakes, professor of environmental engineering for buildings at Leeds University and the chair of SAGE’s environmental working group, which set the two-metre rule, said in The Guardian that the number of people infected in a community was important in shaping government policy.

Her comments were based on the fact that – at the time – about 1,000 people a day were testing positive – something that is still the case.

She said: “If you’re in a big theatre venue, someone in that space will have the virus. If you’re on the bus, 1 in 20 buses will have someone infected on it. At the end of the day, it’s what risks society is willing to tolerate.”

Currently, the government says the incidence of the disease across the UK is 1 in 1,700.

Chief scientific officer Sir Patrick Vallance said in a recent media briefing that the “one-metre plus” rule was as safe as the two-metre rule, so long as mitigations were in place.

So, should you use the two-week rate of infection to decide whether it is safe to go to the pub, to a restaurant, to the shops without a mask, or anywhere else where you live?

According to experts, the answer is yes and no.

The two-week infection rate is a potentially useful general indicator of risk, but there are many other variables that people need to take into consideration if they are to protect themselves.

Factors that have a significant bearing on the risks you face include the make-up of your household, the number of people you meet outside your house, how many those people have met, the types of places you go, and the age profile of the area you live in.

Prof McConway said: “There will be some people who have got it and they haven’t been tested – maybe they’re asymptomatic. You can’t say just because there have been no cases in two weeks in an area that actually there’s no infection there.

“If you’re in a big theatre and one person’s got it… that doesn’t mean that you will get it.

“There are examples from before lockdown started of super-spreaders… where quite a lot of people got it from probably one infected person. In many, but not all of those cases, most people didn’t get infected. If you were upstairs in the gods [of a theatre] and the one person had it in the stalls, you were probably okay.”

Dr Yuliya Kyrychko, reader in mathematics at the University of Sussex and the other co-creator of a COVID-19 simulator, said: “You can say that the more people are infected in a particular area, the more likely you are to get infected, but at the same time, we have to bear in mind age differences and structures of transport networks and everything.

“Younger people tend to interact more, so the risk of infection spreading will be higher.

“If people are outdoors, not inside, the risk should be lower.

“But, we are talking about confirmed cases and there are lots of asymptomatic carriers. They will still spread the disease, but we don’t know how many of those there are.”

The two-week rate doesn’t always take localised outbreaks into account.

It does not show that, for example, flare ups like the outbreak at a meat processing factory in Anglesey, where dozens of people have tested positive in a short time. It is likely to be this that is responsible for Anglesey’s high two-week rate.

Such spikes in infections can only become apparent after wider-scale testing and track-and-trace operations are under way.

But by tracking the daily infection rates in an area, it might be possible to know how recently a localised outbreak occurred.

Another way for people to gauge the degree of risk they face in catching COVID-19 might be to look at the R number in their area.

R, or the “reproduction number”, refers to the number of people, on average, an infected person can pass the virus on to, assuming no pre-existing immunity and no social distancing measures in place.

At the start of the outbreak, COVID-19’s R number was estimated as being between 2 and 3. When the number is well below 1, diseases die out.

But this number varies in different populations and it changes over time. It is very much affected by people’s behaviour and restrictions such as lockdown.

The government is publishing SAGE’s estimate of the R number every week. This number does not come from a single model, but SAGE uses different academic groups to come to a consensus. This is because the result of each model varies.

The R number is one of the most important metrics to understand an epidemic, and how likely you are to be infected.

The other uncertainty, already mentioned by the experts, is people carrying the virus, although many of them might have not tested positive.

Between 26 April and 13 June, Public Health England (PHE) figures say there were an average of 6,200 infections a week in England. However, this does not include people who are infected but do not test positive – either because they are not showing symptoms or because they do not get tested.

The Office for National Statistics has done work on the true level of infection, taking this into account.

The latest ONS study estimated that there have been an average of 26,900 new COVID-19 infections per week in England between 26 April and 13 June – more than four times higher than what the PHE figures suggest.

Another factor in assessing how much risk we face concerns the people we meet – and how much they are moving around.

If the authority you live in has a low two-week infection rate – but the one next door has a high one and many people from that authority regularly come into yours – there is a greater chance of meeting an infected person.

Despite sustained levels of infection, experts say people are moving much more than they were just a few weeks ago.

A group of experts from the University of Oxford has estimated the proportion of people staying at home since middle of March using data from mobile phones.

A person is considered to stay at home if they don’t move more than 100m from their property.

The share of people staying at home started to increase considerably around 20 March, when schools, pubs and restaurants were closed. Four days later, the national lockdown was put in place.

But as restrictions have been lifted, people have been at home less in recent weeks.

Data used by the Oxford COVID-19 Impact Monitor is based on a representative sample of anonymised and aggregated mobile phone data. A sample is just a proportion of the population, and not everyone who carries a smartphone is considered in the estimation.

But other sources of phone location data such as Google or Apple also show how people across the UK are moving around more and more.

Experts say that, as people move around more, the risk to others may increase – even if infection rates appear low in their area.

Prof McConway added: “In Milton Keynes, where I live, the geographical area of it is fairly small and lots of people come here to do their shopping. So they’ll be coming from Bedford, where the last time I looked, the infection rate was quite high. It’s only 14 miles away. So if you go to the local shopping centre, you may be at a bit higher risk than is indicated by the number of infections [in Milton Keynes].

“This is particularly the case for places like London boroughs, where everyone moves over the boundaries. People are coming to work in London from 30, 40, 50 miles away, and you pass someone in a shop or in your workplace and they might come from a hotspot. You really can’t tell.

“It depends on your actions and particularly those of other people that you don’t know about.”

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