| Background:
| Background:
Home How likely are you to catch Covid-19 if you live in Buckinghamshire – 21 June to 14 July

How likely are you to catch Covid-19 if you live in Buckinghamshire – 21 June to 14 July

This post is designed to help you understand the risk of catching Covid-19 if you live in Buckinghamshire today, Tuesday 14th July. BuDS researchers have looked at data and statistics which have been published by Government, NHS and academic bodies, and a clinical epidemiologist has reviewed all our work. We are confident that what we say is as accurate and balanced as it can be using public data. If you go to our website, you can also see all the places we got our information from.

You catch Covid-19 from being around other people who have Covid-19. People who are infected breathe out tiny droplets of water containing the virus which float in the air for a while. If you breathe in the droplets, you can catch the virus. The tiny droplets containing the virus also get onto things, like a door handle. If you touch those things and then touch your face, the droplets can get into your body through your mouth, nose or eyes and you can get infected. But the virus in the droplets, whether in the air or on surfaces, die out after a while. Because of this, you can’t catch Covid-19 very easily unless you meet other people who have Covid-19 or visit places where they have been quite soon before you. Covid-19 is like a ‘small cloud of possible infection’ that follows people who are infected, not a poison that contaminates places for a long time.

So, it really matters how many people in Bucks have Covid-19 right now. If only a very few people in Buckinghamshire have Covid-19, the risk of coming across someone with the virus or visiting somewhere they have just been is very low. On the other hand, if lots of people in Buckinghamshire have Covid-19, then there is a much higher risk that you will come across someone with the virus or visit somewhere they have just been. So, understanding how many people have the virus right now in Buckinghamshire is important to understanding how risky it is to meet other people.

However, the Government deliberately conceals detailed data about Covid-19 in the UK. Only bits of data are published – most of what is shown to the public is only about the position on any particular day. They also use very confusing measuring methods. Because of this, what we say below is only rough calculations. However, we do think it is good enough for you to use to make decisions.

We know from Public Health England data that in the three weeks between 21st June and 11th July, 64 people tested positive for Covid-19 in Bucks1. We know from the World Health Organisation that most people outside hospital have active symptoms of coronavirus for around three weeks2, so these are the people who potentially could infect you. We also know from published studies that about 80% of people with Covid-19 show no symptoms and so are not tested3. Adding these untested people to our total brings us up to roughly 320 people with Covid-19 right now in Buckinghamshire. (This will change – it may go up, or it may go down).

Some at least of these 320 people with Covid-19 will be showing symptoms and self-isolating or even in hospital. Some sadly may have died and some may no longer be infectious. But, for the purposes of calculating risk, we will assume that they are all out in the community potentially able to infect you. How likely are you to meet them?

320 people in the population of Bucks is about 6 people in every 10000 people4. The population of Aylesbury is about 60,0005, so (mathematically) there could be roughly 35 people infected with Covid-19 living in the whole of the town. High Wycombe has a population of 120,0006, so (mathematically) there could be roughly 71 people infected with Covid-19 living in the whole of the town. On a busy Saturday, about 8 to 12,000 people might travel through Aylesbury or Wycombe town centres, and perhaps 5 to 7 of them (mathematically) would be infected with Covid-19. A large event like Parklife or the Bucks County Show attracts over 20,000 people over the day and (mathematically) 11 or 12 of those people will be infected with Covid-19.

Last week, looking at the three weeks before 5th July, there were about 290 infected people in Buckinghamshire. This week, looking at the three weeks before 12 July, there are 320 infected people, a rise of 30 cases or 10%. This is why the number of infected people in Bucks has risen from 5 in every 10,000 to 6 in every 10,000. It is important to remember that although the number of infected people in Bucks has risen, it is still a very small rate of infection, so the risk of meeting an infected person hasn’t got much worse.

Another way of thinking about this is to look at Leicester. A local lockdown in the city has been imposed because they currently have 106 people in every 10,000 testing positive7, nearly 18 times more than in Bucks. If Bucks had the same rate of positive cases as Leicester, we could have over 5700 infected people walking around in Bucks rather than about 3208,9.

Remember, these are mathematical calculations, not actual predictions. There could be more infected people actually present on any one day in any place than the numbers suggest, or fewer. Remember too that one person with Covid-19 could infect dozens or even hundreds of other people if precautions aren’t taken to limit infection. Small numbers can rapidly become large numbers, which is why social distancing, washing hands and wearing face masks remains important to keep numbers low.

Also, of course. you don’t necessarily have to meet 10,000 people to meet one with Covid-19. The first person you see in the street or supermarket might be the one person with Covid-19.


Today, 14 July, your chance of coming across someone in Buckinghamshire who can infect you with Covid-19 is mathematically small, unless you meet huge numbers of people in your life. The risk of you catching Covid-19 is therefore small. However, as we have shown in another post, for some people, catching Covid-19 can be very serious.


If you use sensible safety precautions, and avoid high-infection-risk people and high-infection-risk places, you can reduce your risk still further. We will be making another post about precautions, so this is just a summary. Remember, for some people, catching Covid-19 can be very serious even if the risk of catching it is low.

Sensible safety precautions include using a face mask or covering in crowded places, washing your hands often, and most importantly trying to keep away from other people, at least 2 metres.

High-infection-risk places to avoid are places where groups of people gather at certain times, such as town centres, shopping centres, bigger schools, supermarkets, railway and bus stations, big offices and factories, crowded parks and streets, and of course beaches, stadiums, cinemas, and events. Inside places are much more risky than outside places. If you do need to go to high-infection-risk places, you should take extra care and use safety precautions.

High-infection-risk people to avoid are people who work at or go to high-infection-risk areas, like health and care workers, shop workers, teachers, and transport workers. People whose work means they meet a lot of people are also high-infection-risk, like police officers, doctors and nurses, vicars, priests and religious leaders. If you do need to see high-infection-risk people, you should take extra care and use safety precautions.


BuDS is keeping a very close eye on the statistics and will put out another post next week using the latest figures.

[1] Based on calculations using rate figures and daily case announcements from the Government – https://coronavirus.data.gov.uk/#category=utlas&map=case, https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/897199/Weekly_COVID19_Surveillance_report_-_week_27.pdf, https://www.bbc.co.uk/news/uk-51768274,

[2] https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf

[3] https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/articles/coronaviruscovid19infectionsinthecommunityinengland/july2020

[4] Assuming population of 543973 based on 2018 survey data, https://www.bbc.co.uk/news/uk-51768274

[5] https://www.aylesburytowncouncil.gov.uk/about-aylesbury/#:~:text=Aylesbury%2C%20the%20County%20Town%20of%20Buckinghamshire%2C%20is%20a,of%20over%2060%2C000%2C%20the%20largest%20in%20Aylesbury%20Vale.

[6] https://www.wycombe.gov.uk/pages/About-the-council/Transparency-and-open-government/Open-data/Statistics-and-census-information.aspx

[7] Based on calculations from rate figures and case numbers issued by the government, https://coronavirus.data.gov.uk/#category=utlas&map=case – population data from https://www.ukpopulation.org/leicester-population/

[8] Based on calculations replacing the true percentage of cases in Bucks with that of Leicester, but keeping all other variables the same

[9] This number appears lower than the 6000 quoted in last week’s update which is unexpected given the rate of new cases in Buckinghamshire has risen, but this is because the reported rate of new cases in Leicester has fallen more relative to its population than the rise in Buckinghamshire.