Coronavirus disease (COVID-19) is caused by the coronavirus SARS-CoV-2. How is the coronavirus SARS-CoV-2 spreading and what can you do to prevent it from spreading?

From person to person

You can become ill if you are infected with SARS-CoV2, the coronavirus that causes COVID-19. Your body defends itself against the virus in different ways. The first line of defence is your skin. It forms a kind of wall around your body that is impenetrable to many pathogens. In addition, there are numerous other lines of defence that a pathogen must pass through before you can become ill, such as your immune system. For that reason, a single virus particle is rarely enough to make you sick. You will (usually) have to come into contact with many virus particles before you become ill.

A person who is ill from the coronavirus SARS-CoV-2 produces millions of copies of the virus inside their body. The virus is mainly found in the lungs, but also in other ‘moist’ parts of your body, such as your throat or nasal cavity. When you sneeze or cough, you are not just pushing out air: lots of droplets also come out of your lungs, throat or nasal cavity. The coronavirus SARS-CoV-2 spreads through these droplets.

COVID-19 spreads very quickly from human to human. Watch this video and see how this works.

Coughing or sneezing

A person who is ill from the coronavirus SARS-CoV-2 produces millions of copies of the virus inside their body. The virus is mainly found in the lungs, but also in other ‘moist’ parts of your body, such as your throat or nasal cavity. When you shout or scream, you are not just pushing out air: lots of tiny droplets also come out of your lungs, throat or nasal cavity. The coronavirus SARS-CoV-2 spreads through these droplets. If other people inhale those droplets, or get them in their mouth, nose or eyes, for example via their hands, they could become infected with the virus.  

Large or small droplets

Although the coronavirus SARS-CoV-2 is still a fairly new virus, and there is much we still do not know about it, we do know that other people are mainly infected via the somewhat larger droplets. The larger droplets do not travel as far (rarely making it beyond 1.5 metres). Under normal circumstances, it would appear that there is a minimal risk of spreading the coronavirus SARS-CoV-2 through the small droplets that remain suspended in the air (known as aerosols). This is also supported by various scientific articles on this subject. This information also shows that ventilation systems (like air conditioners) do not seem to play a role in spreading the coronavirus SARS-CoV-2. (Read the document on ‘Aerogenic spread of SARS-CoV-2 and ventilation systems’ – only in Dutch). It seems as though the virus may be in the small aerosolised droplets, but that the dose of virus in these smaller droplets is usually not enough to infect someone, except in very high concentrations, such as when ventilating a COVID-19 patient in intensive care. The clearest indication for this is the reproduction number (R0) for the coronavirus SARS-CoV-2. This number indicates how many people will be infected by a sick person without any preventive measures. The coronavirus SARS-CoV-2 has a reproduction number between 2 and 4. Diseases that spread through tiny droplets and remain ‘suspended’ in the air for a long time have a higher reproduction rate. Well-known examples include tuberculosis and measles. A person who has the measles virus will infect about 17 other people (without measures such as isolation or vaccination).

Visual spread COVID-19 droplets

Keep your distance

In the Netherlands, it is recommended to stay 1.5 metres (2 arm lengths) apart from others. This reduces the risk that people will infect each other and prevents the coronavirus from spreading. It is known that most droplets that are released during coughing or sneezing do not travel further than 1 to 2 metres. An article in medical journal The Lancet recently showed that the policy of staying at least 1 metre apart was effective, but stated that 2 metres might be better. However, there was no clear evidence to support this. Countries interpret this information differently. That is why 1 metre is the rule in some countries (such as Denmark and China), while others require 2 metres (such as Spain and the United Kingdom), and some countries have advised a minimum distance of 1.5 metres (the Netherlands, Australia, Belgium).

Surfaces

It also seems unlikely that the coronavirus SARS-CoV-2 is spread via parcels or surfaces (such as a door or shopping cart). Although it has been demonstrated in the laboratory that this is possible, that experiment was done under ideal conditions that will rarely occur in actual practice. The most important thing is: minimise your risk and wash your hands regularly.

How to prevent the coronavirus SARS-CoV-2 from spreading

  • Wash your hands often with soap. This will remove the virus from your hands, making it harder to infect yourself or others.
  • Avoid touching your face with your hands as much as possible. This reduces the risk that you will become infected if you have the virus on your hands, and makes it less easy for you to infect others.
  • Cough and sneeze into your elbow, to keep the virus off your hands.
  • Use paper tissues to blow your nose and discard them after use.
  • Do not shake hands. Avoiding hand contact makes it harder for the virus to spread via hands.
  • Stay 1.5 metres (2 arm lengths) apart from others. This makes it harder for the virus to spread via (accidental) coughing or sneezing.
  • Work from home, unless it is absolutely necessary that you go to work. If people have less contact with each other, the virus cannot spread as easily. 
  • Stay at home as much as possible.
Visual do not allow the spread of COVID-19

Download the poster COVID-19 story part 2: spread and control

The government has implemented measures to prevent the coronavirus SARS-CoV-2 from spreading. See the Dutch response and coronavirus measures.

Questions about how the virus spreads

Can I become infected with the virus SARS-CoV-2 from food?

When preparing food, it is important to always follow the hygiene measures. This prevents infections with all kinds of pathogens, such as salmonella. There is no evidence that the virus spreads through eating or preparing food. Also, coronaviruses need a living animal or human to grow and reproduce, in contrast to bacteria such as Salmonella. That means that the coronavirus SARS-CoV-2 cannot grow in food.

Can the coronavirus SARS-CoV-2 spread through glasses, crockery or cutlery?

It is possible to contract an infection involving bacteria or viruses via surfaces. The chance of getting a glass that has been used by someone that is currently shedding the virus is small right now. This is because people with symptoms have to stay home. The risk of contracting the virus by drinking from a glass that has been used by someone who does not have any symptoms yet, but still turns out to have the virus, is small, but present. To minimise that risk as much as possible, it is important to ensure that the glass is properly cleaned. The same goes for crockery and cutlery. In most cases, infection occurs via droplets from sneezing / coughing and via hands. For that reason, you should follow the current hygiene guidelines and measures which apply to everyone.

Can you get infected by using the shower or toilet area at such locations as a campsite / swimming pool?

The risk that the coronavirus SARS-CoV-2 will spread by using a communal shower or toilet at the campsite or swimming pool is minimal. The virus may possibly be present in faeces or urine, but there is no evidence of infection via a toilet. The coronavirus is transmitted through small droplets released when an infected person coughs and sneezes. If you are standing nearby and you inhale those droplets, or get them on your hands and then into your mouth, nose or eyes, you may become infected with the virus. You should therefore stay at least 1.5 metres apart from others and wash your hands regularly with soap and water – including right before you leave the shower or toilet area. Also, it is important that public toilets and shower rooms are cleaned regularly according to the general hygiene guidelines and that these indoor spaces are well ventilated.

Can I use a fan or air conditioning?

The page on Heat and COVID-19 offers an answer to this question and other questions about warm weather and COVID-19.  Or take a look at the document addressing the role of ventilation in spreading the coronavirus SARS-CoV-2 (only in Dutch).

Is it safe to make music (e.g. singing or playing a wind instrument) with a band/choir/ensemble/music society?

There may be an increased risk of spreading the coronavirus SARS-CoV-2 if people sing or play wind instruments in a group setting. This possibility is still being investigated. A guideline is being drawn up for choirs and (amateur) singers in groups. Go to government.nl for more information about the measures and possibilities.

Can people pass on the coronavirus SARS-CoV-2 before they have symptoms?

The latest scientific insights (in Dutch) show that people may be contagious as soon as they develop the very first symptoms. Because those symptoms are sometimes very mild, it is unclear whether people are contagious even before they start showing symptoms. That is why contact tracing includes an infected person's contacts starting two days before the first clear symptoms.

Can I get infected by cigarette smoke from a person with COVID-19?

Blowing out cigarette smoke is probably no different than exhaling normally. The risk of infection is therefore the same as the risk from a non-smoker. However, smokers may cough more than people who do not smoke. Regardless, people should stay 1.5 metres apart at all times to avoid infecting each other. People who smoke should be aware of the increased risks. Smokers are more vulnerable to the coronavirus SARS-CoV-2.

Can I have sex?

You can catch and pass on COVID-19 by having sex. During sex, you are closer than 1.5 metres. 

Having sex with yourself or sex at a distance of 1.5 meters (for example online) does not pose a risk of catching COVID-19. Having sex with a partner who lives in the same household does not pose any additional risk of catching COVID-19, since you are already frequently close together.

Do you want to have sex who does not live in your household? Then it is important to minimise the risk of catching COVID-19.

In the following situations, the advice is not to have sex:

  • You have (mild) symptoms which could indicate COVID-19. Stay home and get tested. Are the symptoms getting worse? Contact your family doctor (GP).
  • Is your test negative? Then you can have sex again.
  • You have a confirmed COVID-19 infection and are in isolation.
  • Someone in your household has a confirmed COVID-19 infection or has (mild) symptoms with fever and/or shortness of breath and you are in quarantine. 

For more information about sex and COVID-19, see:
Soaaids.com: Answers to frequently asked questions about coronavirus, sex and STIs
Rutgers.nl Advice for sex during corona (in Dutch)
 

Can you kiss your partner?

You can kiss your partner. However, you can contract the novel coronavirus from kissing, and pass it on to your partner the same way. If your partner has symptoms that could indicate COVID-19, then do not kiss. The advice to stay 1.5 metres apart from others also means that you should not kiss other people.