Coronavirus disease (COVID-19): Prevention and risks

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How COVID-19 spreads

COVID-19 spreads from an infected person to others through respiratory droplets and aerosols created when an infected person coughs, sneezes, sings, shouts, or talks. The droplets vary in size from large droplets that fall to the ground rapidly (within seconds or minutes) near the infected person, to smaller droplets, sometimes called aerosols, which linger in the air under some circumstances.

The relative infectiousness of droplets of different sizes is not clear. Infectious droplets or aerosols may come into direct contact with the mucous membranes of another person's nose, mouth or eyes, or they may be inhaled into their nose, mouth, airways and lungs. The virus may also spread when a person touches another person (i.e., a handshake) or a surface or an object (also referred to as a fomite) that has the virus on it, and then touches their mouth, nose or eyes with unwashed hands.

Learn more about modes of transmission of COVID-19.

Difference between quarantine and isolate

People are asked to quarantine or isolate to help prevent the spread of COVID-19 to others. Although these two words are often thought to mean the same thing, there's an important difference.


If you have no symptoms and any of the following apply to you, you must quarantine for 14 days (starting from the date you arrive in Canada):


You must isolate if any of the following apply:

Preventing COVID-19

Vaccination for COVID-19

Learn about our vaccine progress, the safety of the authorization process and what vaccines have been authorized for use in Canada.

Flu vaccine

Getting your annual flu shot is the best way to protect yourself, your family and people at high risk of complications from the flu. It will help:

The flu shot will not protect against COVID-19, but it will help reduce your risk of getting the flu and COVID-19 at the same time. Having both illnesses at the same time could put you at a higher risk for severe complications.

Getting the flu shot will not increase your risk of illness from COVID-19. For more information, please refer to this Canadian research study.

Follow public health measures

Canadians should continue to think ahead about the actions that they can take to stay healthy and prevent the spread of COVID-19 in Canada. Measures to reduce COVID-19 in your community are especially important as some areas begin to lift restrictions.

Everyone is advised to avoid or keep exposure very brief with people outside of their immediate household.

Hand hygiene and respiratory etiquette

Maintaining good hand and respiratory hygiene are very important personal practices that help reduce the risk of infection or spreading infection to others.

  • Wash your hands often with soap and warm water for at least 20 seconds.
    • If soap and water aren't available, use a hand sanitizer containing at least 60% alcohol.
  • When coughing or sneezing:
    • cough or sneeze into a tissue or the bend of your arm, not your hand
    • dispose of any tissues you've used as soon as possible in a lined waste basket and wash your hands immediately afterwards
  • Avoid touching your eyes, nose, or mouth with unwashed hands.

Physical distancing

Together, we can slow the spread of COVID-19 by making a conscious effort to keep a physical distance between each other. Physical distancing is proven to be one of the most effective ways to reduce the spread of illness during an outbreak.

This means making changes in your everyday routines to minimize close contact with others, including:

  • avoiding exposure or keeping it very brief in:
    • closed spaces
    • crowded places
    • close-contact settings and close-range conversations
    • settings where there's singing, shouting or heavy breathing (for example, during exercise)
  • avoiding non-essential travel
  • avoiding common greetings, such as handshakes
  • limiting contact with those at risk of more severe illness, such as:
    • older adults
    • those with underlying medical conditions
    • those with compromised immune systems
  • maintaining a physical distance of 2 metres from people outside of your household

Wearing non-medical masks

As community transmission of COVID-19 continues in many areas across Canada, and as new variants of the COVID-19 virus are identified and circulating, it remains important that you wear a non-medical mask when:

  • you're in a shared space (indoors or outdoors) with people from outside of your immediate household
  • advised by your local public health authority

Non-medical masks should be well constructed, well fitting, properly worn and made of multiple layers.


Good indoor ventilation is a part of preventing the spread of COVID-19.

Cleaning and disinfecting

The COVID-19 virus is most likely to be on surfaces you frequently touch with your hands. Clean and disinfect high-touch surfaces to lower the chance of COVID-19 spreading in your home, workplace and public spaces.

Health Canada has published a list of hard surface disinfectants that are likely to be effective for use against COVID-19.

Special precautions must be used when cleaning with bleach to avoid serious incidents.

Caring for someone with COVID-19 at home

When caring for someone with COVID-19, follow the appropriate precautions to prevent the spread of illness.

Risks of getting COVID-19

The risk of getting COVID-19 is evolving daily and varies between and within communities. Overall, the risk to Canadians remains high. This doesn't mean that all Canadians will get the disease. It means that there's already a significant impact on our health care system.

To stay healthy and to protect ourselves and others, we must be mindful of the ever-present risk of exposure to the virus. Some settings and situations increase the risk, such as being in:

It's particularly important to avoid settings where these risks overlap, such as closed spaces and crowded spaces where close-range conversations occur.

Holidays and celebrations

Safety advice to reduce your risk and help prevent the spread of COVID-19 during holidays and celebrations.

People at a greater risk of exposure

Some people may be at greater risk of COVID-19 than others due to their occupational, social, economic, and other health and life circumstances.

You may be more likely to be exposed to the COVID-19 virus because:

  • your job or occupation requires you to be in contact with large numbers of people, which increases your chances of being exposed to someone who has COVID-19
  • you live in a group setting where the COVID-19 virus may transmit more easily
    • for example, long-term care facilities, correctional facilities, shelters or group residences
  • you face barriers that limit your ability to access or implement effective public health measures
    • for example, individuals with disabilities who encounter non-accessible information, services and/or facilities

To reduce your risk, and to reduce the spread of COVID-19 to your loved ones:

  • if you have any symptoms, even mild ones, stay home, stay away from others and get tested
  • keep up with effective public health practices, such as physical distancing, hand-washing and wearing non-medical masks
  • wear a medical mask if you're experiencing symptoms of COVID-19 and you'll be in close contact with others or going out to access medical care
    • if unavailable, properly wear a well-constructed and well-fitting non-medical mask

People at risk of more severe disease or outcomes

Coronaviruses can result in severe illness for some people in our communities. Those who are at risk of developing more severe disease or outcomes from COVID-19 are people:

  • who are an older adult (increasing risk with each decade, especially over 60 years)
  • of any age with chronic medical conditions, including:
    • lung disease
    • heart disease
    • high blood pressure
    • diabetes
    • kidney disease
    • liver disease
    • dementia
    • stroke
  • any age who are immunocompromised, including those:
    • with an underlying medical condition, such as cancer
    • taking medications which lower the immune system, such as chemotherapy
  • living with obesity (BMI of 40 or higher)

To reduce your risk, and to reduce the spread of COVID-19 to your loved ones:

  • if you have any symptoms, even mild ones, stay home, stay away from others and get tested
  • keep up with effective public health practices, such as physical distancing, hand-washing and wearing non-medical masks
  • wear a medical mask if you're experiencing symptoms of COVID-19 and you'll be in close contact with others or going out to access medical care
    • if unavailable, properly wear a well-constructed and well-fitting non-medical mask

Going out

Think about the risks before going out. Keep yourself and others safe when doing personal and social activities during the COVID-19 pandemic.

Pregnant people

If you're pregnant and concerned about COVID-19, speak to your health care provider.

Because COVID-19 is a new disease, we're still learning how it affects pregnant people. At this time, there's no evidence to suggest that pregnant people are at a greater risk:

  • for more serious outcomes related to COVID-19
  • of having their developing child negatively affected by COVID-19

You can protect yourself from becoming ill by taking the following precautions.

  • Stay home as much as possible, except for important medical appointments.
  • Make limited trips to the store for essentials.
  • Avoid crowded places and peak-hours.
  • Talk to your doctor, obstetrician or midwife about the possibility of telephone or videoconference appointments.
  • Avoid unnecessary visitors to your home.
  • Wash your hands often with soap and water for at least 20 seconds.
    • Use hand sanitizer containing at least 60% alcohol if soap and water aren't available.
  • Practise physical distancing by keeping a distance of at least 2 metres from others.
  • Avoid touching your mouth, nose and eyes without washing your hands first.
  • Avoid travel by public transit as much as possible.

For more information, refer to our advice on pregnancy, childbirth and caring for newborns.


The risk of getting COVID-19 may be increased for travellers. If you must travel, check the latest travel advice before you leave.

If you're a returning traveller (either travelling into Canada, or, in some instances, travelling from one province or territory to another) you'll be required to:

We'll continue to adapt our risk assessment based on the latest data available.

Additional restrictions apply to travellers returning to Canada.

Check if you've been exposed

Have you been on a recent flight, cruise or train trip? Check the listed exposure locations to see if you may have been exposed to COVID-19.

You can also join the effort to limit the spread of COVID-19 with Canada's free COVID Alert app. It notifies you if someone you were near in the past 14 days tells the app they tested positive. Download COVID Alert.

Survival of coronaviruses on surfaces

It's not certain how long the virus survives on surfaces, but it seems to behave like other coronaviruses. Research suggests that the virus may live on surfaces for a few hours or up to several days depending on:

  • temperature
  • type of surface
  • humidity of the environment

Surfaces frequently touched with your own hands or other peoples hands are most likely to become contaminated, including:

  • tables
  • phones
  • handrails
  • doorknobs
  • credit cards
  • countertops
  • light switches
  • faucet handles
  • steering wheel
  • cabinet handles
  • elevator buttons

Packages that you receive in the mail may be contaminated, but because parcels generally take a few days to be delivered, the risk of spread is low.

To protect yourself from COVID-19, make sure to do the following when handling products shipped within or outside of Canada:

  • wash your hands often with soap and water for at least 20 seconds after handling the package
  • avoid touching your eyes, nose or mouth, especially with unwashed hands


There's no evidence that COVID-19 can spread through the water. However, it can spread from person to person through close contact in and around the water. This includes crowded spaces, such as:

  • public:
    • lakes
    • rivers
    • beaches
    • swimming pools
  • pool decks
  • change rooms
  • public washrooms

COVID-19 can also spread through contaminated surfaces. Avoid sharing swimming gear with others. This includes things like:

  • towels
  • goggles
  • pool toys
  • nose clips
  • kick boards
  • snorkel equipment
  • lifejackets that haven't been cleaned after use


There's currently no evidence to suggest that food is a likely source or route of transmission of the virus. There are currently no reported cases of COVID-19 transmission through food.

We're continually working to examine new scientific evidence between food safety and COVID-19. Scientists and food safety authorities around the world are also working closely to share information on COVID-19. We'll continue to update Canadian food safety practices based on the most relevant and recent scientific findings.

If we become aware of a potential food safety risk, appropriate actions will be taken to ensure the safety of Canada's food supply.

Learn more about food safety and healthy eating during the COVID-19 pandemic.

Animals in Canada

The current spread of COVID-19 is a result of human-to-human transmission. There's no evidence to suggest that animals infected by humans are playing a role in the ongoing spread of this disease. Animals and COVID-19 is an area that continues to be studied by scientists.

Learn how to keep pets and livestock, as well as yourself, safe during the COVID-19 pandemic.

Sexual health

Sexual health is an important part of overall health. But sex can be complicated in the time of COVID-19 for:

Because COVID-19 spreads through respiratory droplets, kissing is a high-risk activity. Even if no one's showing symptoms, sexual activity with partners outside of your small, consistent and trusted contact bubble increases your risk of getting or spreading COVID-19. However, current evidence indicates there's a very low likelihood of getting COVID-19 through semen or vaginal fluids.

If having sex with someone outside of your small, consistent and trusted contact bubble, reduce the risk to yourself and others.

  • Monitor yourself for COVID-19 symptoms, and stay home and avoid sex if you or a partner are experiencing them.
  • Limit the use of alcohol and other substances so you and a partner are able to make safe decisions.
  • Avoid kissing and face-to-face contact or closeness.
  • Consider using a non-medical mask that covers your nose and mouth.

In addition to COVID-19 prevention measures, always engage in safe sex practices. This includes using condoms, and knowing both your own and a partner's sexually transmitted infection status.

For more information on how to protect your sexual health in general and during the COVID-19 pandemic, visit:

False and misleading claims

Health Canada is closely tracking all potential drugs and vaccines in development in Canada and abroad. We are working with companies, academic research centres and investigators to help expedite the development and availability of treatments to prevent and treat COVID-19. Learn more about drugs and vaccines being developed or authorized for COVID-19.

Selling unauthorized health products or making false or misleading claims to prevent, treat or cure COVID-19 is illegal in Canada. We take this matter very seriously and we're taking action to stop this activity.

We encourage anyone who has information regarding potential non-compliant sale or advertising of any health product claiming to treat, prevent or cure COVID-19, to report it using our online complaint form.

We publish a list of companies and products and the status of the review on the list of health product advertising incidents related to COVID-19.

Exposure to electromagnetic fields (EMF) from 5G devices doesn't spread COVID-19. There's no scientific basis behind these claims. Both the World Health Organization and the International Commission on Non-Ionizing Radiation Protection have also addressed these claims.

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