Related articles in Covid-19

Danger of Covid-19

How dangerous is Covid-19 if you catch it, really?

This is an article to help you understand how dangerous Covid-19 could be for you if you catch it. We have done another post about how likely it is that you could catch Covid-19 in Bucks. Remember, your risk from Covid-19 is about two things: how likely it is that you could catch the virus, and how dangerous the virus might be if you do catch it. BuDS has covered these two issues in two separate articles.

We have solid data and fact-checked information – read on for more.

 

INTRODUCTION

There is a lot of misinformation and “fake news” about Covid-19, and medical opinion about how dangerous Covid-19 is for people with certain medical conditions is changing all the time. BuDS researchers have set out to collect reliable, fact-checked and up to date information so that disabled and shielding people can make informed decisions. To do so, we 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.

This post does not say how likely it is that you catch Covid-19 or how you can reduce your risk. We have covered those issues in other posts. This post is only about how dangerous Covid-19 might be for you if you catch it. 


 

HOW DANGEROUS IS COVID-19?

How dangerous is Covid-19 in general? Many people say it is not really very dangerous, or no worse than the flu. So, we have looked at the latest figures and come up with some comparisons which may help you.

In the winter of 2018/19, about 2.7 million people caught seasonal flu[1] (for which there was a vaccine) of which 5505 (0.2%)[2] had to be admitted to hospital intensive care units over the whole winter. More than that number were admitted for Covid-19 to hospital intensive care units in June 2020 alone[3].

Again, in the winter of 2018/19, 1692 people sadly died of seasonal flu[4], or 0.06% of those who caught it. We know from NHS figures that, of the over 1.425 million people who have tested positive for Covid-19 in a hospital or in the community[5], or who are likely to have had Covid-19 without a test[6], 44,220 have died, or 3.1%. It is obvious from this that Covid-19 is a lot more dangerous than seasonal flu – its mortality rate is over 50 times as high.

These are figures for the population as a whole. Covid-19, however, is more dangerous for some people than others.


 

PEOPLE FOR WHOM COVID-19 IS MUCH MORE DANGEROUS

Some people are much more likely than others to die or be seriously ill if they catch Covid-19, and some are less likely than average to die or have serious illnesses. The reasons for this are very complicated and not fully understood. However, looking at all the scientific data, and particularly at a recent UK study looking specifically at relative risk[7], BuDS researchers have been able to list the risk factors that could apply to you.

If more than one risk factor in this list applies to you, your risk is even higher. 

 

AGE

Scientific studies based on hospital records show clearly that being older *massively* increases your risk of dying or having a serious illness if you catch Covid-19, and the older you are, the higher your risk. This is because your immune system works less well as you get older, however fit you are.

In the table below, older people without any underlying medical conditions are compared to someone under 40 also without any underlying medical conditions, so the increased risk is simply the effect of age.

Over 80: 180 times more likely to die or have a serious illness if they catch Covid-19[8]

70 to 79: 68 times more likely to die or have a serious illness if they catch Covid-19[9]

60 to 69: 30 times more likely to die or have a serious illness if they catch Covid-19[10]

50 to 59: 14 times more likely to die or have a serious illness if they catch Covid-19[11]

Being over 50 increases your clinical risk of dying or being seriously ill if you catch Covid-19 much more than if you have a serious medical condition for which you are advised to shield. In fact, a person under 40 with a ‘shielding condition’ like recent cancer, severe COPD, or an organ transplant is still at much less risk of dying or being seriously ill if they catch Covid-19 than a healthy person over 60[12].

On the clinical evidence, all older people should have been included in the shielding group from the start of the pandemic, as they were in other European countries.

 

UNDERLYING MEDICAL CONDITIONS

If you have been recognised by the Government, the NHS or your own doctors as being ‘exceptionally clinically vulnerable’ to Covid-19 because of a medical condition you have, then you are more likely to die or have a serious illness if you catch Covid-19 compared to people without those conditions.

Here are the risk factors for each of the shielding conditions. The comparison is with someone the same as the patient but without the medical condition:

Had an organ transplant: 4.3 times more likely to die or have a serious illness if you catch Covid-19[13]

Having chemotherapy or antibody treatment for cancer, including immunotherapy, having an intense course of radiotherapy (radical radiotherapy) for lung cancer; having targeted cancer treatments that can affect the immune system (such as protein kinase inhibitors or PARP inhibitors); having blood or bone marrow cancer (such as leukaemia, lymphoma or myeloma): 1.7 times more likely to die or have a serious illness if you catch Covid-19.[14]

Having had a bone marrow or stem cell transplant in the past 6 months, or are still taking immunosuppressant medicine; having a condition that means they have a very high risk of getting infections such as SCID or sickle cell; or are taking medicine that makes them much more likely to get infections such as high doses of steroids or immunosuppressant medicine: 1.7 times more likely to die or have a serious illness if you catch Covid-19.[15]

Severe lung condition such as cystic fibrosis, severe asthma or severe COPD: 1.8 times more likely to die or have a serious illness if you catch Covid-19.[16]

Diabetes: If it is controlled, 1.5 times more likely to die or have a serious illness if you catch Covid-19. If it is uncontrolled, 2.4 times more likely to die or have a serious illness if you catch Covid-19.[17]

Stroke & Dementia: 1.8 times more likely to die or have a serious illness if you catch Covid-19.[18]

Neurological Disease: 2.5 times more likely to die or have a serious illness if you catch Covid-19.[19]

 

SMOKING

If you are a smoker or ex-smoker, you are 1.3 times more likely to die or have a serious illness if you catch Covid-19 compared to someone who has never smoked. [20]

 

ETHNICITY

If you are of the ethnic origin in the table below, your extra risk is as shown compared to a white person of the same age, gender, etc. (This may be due to the way Covid-19 affects the bodies of people from ethnic minority groups or it may be because people from ethnic minority groups are more likely to have underlying conditions which make them more susceptible to Covid-19).

Black: 1.7 times more likely to die or have a serious illness if you catch Covid-19.[21]

Asian: 1.6 times more likely to die or have a serious illness if you catch Covid-19.[22]

Mixed race: 1.6 times more likely to die or have a serious illness if you catch Covid-19.[23]

Other: 1.3 times more likely to die or have a serious illness if you catch Covid-19.[24]

 

SEX

If you are male, you are twice as likely to die or have a serious illness if you catch Covid-19 than if you were female.[25]

 

BODY MASS INDEX (Weight in kg/ (height in m)2)

If you are overweight (have a high BMI), you are at higher risk of dying or having a serious illness if you catch Covid-19 than people who are not overweight. (You can check your BMI here: https://www.nhs.uk/live-well/healthy-weight/bmi-calculator/)

Overweight (BMI of 25 to 29.9): 1.3 times likely to die or have a serious illness if you catch Covid-19.[26]

Obese (BMI 30 – 39.9): 1.6 times likely to die or have a serious illness if you catch Covid-19.[27]

Morbidly Obese (BMI 40+): 2.3 times likely to die or have a serious illness if you catch Covid-19.[28]

 

OTHER CONDITIONS

There are other medical conditions which may increase your risk, but the data for these is not sufficiently clear for us to be able to list them as definite risk factors.


 

ADDING UP YOUR RISK SCORE

Obviously, the more risk factors you have, the more you should take precautions against catching Covid-19, because there is an even higher chance that you could die or be seriously ill if you do. You can’t literally add up your risk score (eg Black + Male + Smoker + Recent Cancer) but certainly the more risk factors you have, the more dangerous Covid-19 is for you.

If you have risk factors, then the more you need to think about keeping yourself safe. We give you advice on this below – see ‘Reducing Your Risk’.


 

PEOPLE UNDER 50, YOUNG PEOPLE & CHILDREN

Scientific studies also show that people under 50 have a lower than average risk of dying or having serious illness if they catch Covid-19, with the risk getting less the younger you are. Other scientific studies show that about 80% of people without risk factors who catch Covid-19, including children and young people, do not feel ill at all and show no symptoms[29].

If none of the risk factors apply to you and you are under 50, you might feel it’s relatively safe to run the risk of catching Covid-19, or you might think that the risk of Covid-19 making you seriously ill is not worth the trouble of taking precautions not to catch it. This is not a scientifically valid point of view, because some people with low or no risk factors, and some children and young people, do die or have serious illness when they catch Covid-19. It is much better for people not to catch this dangerous disease. But if you wish to take the risk, that is your decision, as long as you think about the risk you are to other people too (see below).

In summary, the latest scientific data shows that, for older and many disabled and ill people, Covid-19 is a very high-risk virus, while for younger, healthy people, it carries a lower risk.


 

REDUCING YOUR RISK

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 is low.

Sensible safety precautions include using a face mask or covering in crowded places and indoor public 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 hundreds 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, museums and events. Inside places are much riskier 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, security guards and transport workers. People whose work means they meet a lot of people are also a high-infection-risk, such as 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.


 

EVEN IF YOU THINK YOU’RE NOT GOING TO CATCH COVID-19

Some people, especially younger people and those with no risk factors, might think that the risk of Covid-19 making them seriously ill is not worth the trouble of taking precautions to avoid catching it. That is not a scientifically valid point of view, because some people with low or no risk factors do die or have serious illness when they catch Covid-19. It is much better for people not to catch this dangerous disease.

However, even if you are taking risks with your own health, you MUST still protect other people by staying away from older and shielding people and people with other high risk factors, wearing a mask/face covering in public places and keeping your distance from other people. Everyone who runs a high risk of having Covid-19 because of their personal attitude to risk, the places they go, the people they meet or the job they do, has a social and moral duty to protect the other people who they may infect. Please don’t be antisocial and selfish by risking the lives of others.


 

UPDATES

The post was correct at time of writing in July 2020

This post will be updated as soon as we have new data which changes what we say above.


[1] https://www.gov.uk/government/news/uk-flu-levels-according-to-phe-statistics-2018-to-2019

[2] https://www.gov.uk/government/news/uk-flu-levels-according-to-phe-statistics-2018-to-2019

[3] https://www.cebm.net/covid-19/covid-19-uk-hospital-admissions/

[4] https://www.gov.uk/government/news/uk-flu-levels-according-to-phe-statistics-2018-to-2019

[5] https://www.gov.uk/guidance/coronavirus-covid-19-information-for-the-public#dashboard-of-coronavirus-cases-and-deaths

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

[7] https://www.researchgate.net/publication/341226344_OpenSAFELY_factors_associated_with_COVID-19-related_hospital_death_in_the_linked_electronic_health_records_of_17_million_adult_NHS_patients

[8] https://www.researchgate.net/publication/341226344_OpenSAFELY_factors_associated_with_COVID-19-related_hospital_death_in_the_linked_electronic_health_records_of_17_million_adult_NHS_patients – page 8, calculated based on the risk relative to someone under 40 rather than to base reference given

[9] Ibid.

[10] Ibid.

[11] Ibid.

[12] Based on comparison to figures on page 9 and 10 of the same document (https://www.researchgate.net/publication/341226344_OpenSAFELY_factors_associated_with_COVID-19-related_hospital_death_in_the_linked_electronic_health_records_of_17_million_adult_NHS_patients)

[13] . – page 10https://www.researchgate.net/publication/341226344_OpenSAFELY_factors_associated_with_COVID-19-related_hospital_death_in_the_linked_electronic_health_records_of_17_million_adult_NHS_patients – page 10

[14] Ibid. pg 10

[15] Ibid.pg 10

[16] Ibid. pg 9

[17] Ibid. pg 10

[18] Ibid. pg 10

[19] Ibid. pg 10

[20] Ibid. pg 9

[21] Ibid. pg 9

[22] Ibid. pg 9

[23] Ibid. pg 9

[24] Ibid. pg 9

[25] Ibid. pg 9

[26] Ibid. pg 9

[27] Ibid. pg 9

[28] Ibid. pg 9

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