Primary prevention

General prevention measures

  • The only way to prevent infection is to avoid exposure to the virus and people should be advised to:[82][83]

    • Wash hands often with soap and water or an alcohol-based hand sanitiser and avoid touching the eyes, nose, and mouth with unwashed hands

    • Avoid close contact with people (i.e., maintain a distance of at least 1 metre [3 feet]), particularly those who have a fever or are coughing or sneezing

    • Practice respiratory hygiene (i.e., cover mouth and nose when coughing or sneezing, discard tissue immediately in a closed bin, and wash hands)

    • Seek medical care early if they have a fever, cough, and difficulty breathing, and share their previous travel and contact history with their healthcare provider

    • Avoid direct unprotected contact with live animals and surfaces in contact with live animals when visiting live markets in affected areas

    • Avoid the consumption of raw or undercooked animal products, and handle raw meat, milk, or animal organs with care as per usual good food safety practices.

Medical masks

  • Recommendations on the use of face masks in community settings vary between countries.[84]

  • The World Health Organization (WHO) does not recommend that people wear a medical mask in community settings if they do not have respiratory symptoms as there is no evidence available on their usefulness to protect people who are not ill. However, masks may be worn in some countries according to local cultural habits. Individuals with fever and/or respiratory symptoms are advised to wear a mask and seek medical care as soon as possible. Use of a mask alone is insufficient to provide adequate protection, and they should be used in conjunction with other infection prevention and control measures.[85][86]

  • It is mandatory to wear a medical mask in public in certain areas of China, and local guidance should be consulted for more information.

  • It is important to wash your hands with soap and water (or an alcohol-based sanitiser) prior to putting on a face mask.[87]

Screening and quarantine

  • People travelling from areas with a high risk of infection may be screened using questionnaires about their travel, contact with ill persons, symptoms of infection, and/or measurement of their temperature. Combined screening of airline passengers on exit from an affected area and on arrival elsewhere has been relatively ineffective when used for other infections such as Ebola virus infection, and has been modelled to miss up to 50% of cases of COVID-19, particularly those with no symptoms during an incubation period, which may exceed 10 days.[88] Symptom-based screening processes have been reported to be ineffective in detecting SARS-CoV-2 infection in a small number of patients who were later found to have evidence of SARS-CoV-2 in a throat swab.[89]

  • Enforced quarantine has been used in some countries to isolate easily identifiable cohorts of people at potential risk of recent exposure (e.g., groups evacuated by aeroplane from affected areas, or groups on cruise ships with infected people on board).[90] The psychosocial effects of enforced quarantine may have long-lasting repercussions.[91][92]

Social distancing

  • Many countries are implementing mandatory social distancing measures in order to reduce and delay transmission (e.g., city lockdowns, school and university closures, screening measures at airports and train stations, restriction of movement, remote working, quarantine of exposed people). Although the evidence for social distancing for COVID-19 is limited, it is emerging, and the best available evidence appears to support social distancing measures to reduce the transmission and delay spread. The timing and duration of these measures appears to be critical.[93][94]

  • Researchers in Singapore found that social distancing measures (isolation of infected individuals and family quarantine, school closures, and workplace distancing) significantly decrease the number of infections in simulation models.[95]

Shielding extremely vulnerable people

  • Shielding is a measure used to protect vulnerable people (including children) who are at very high risk of severe illness from COVID-19 because they have an underlying health condition. Shielding involves minimising all interactions between those who are extremely vulnerable and other people to protect them from coming into contact with the virus. 

  • Extremely vulnerable groups include:[96]

    • Solid organ transplant recipients

    • People with specific cancers

    • People with severe respiratory conditions (e.g., cystic fibrosis, severe asthma, or COPD)

    • People with rare diseases or inborn errors of metabolism that increase the risk of infections (e.g., sickle cell anaemia, severe combined immunodeficiency)

    • People on immunosuppression therapies sufficient to significantly increase the risk of infection

    • Women who are pregnant with significant heart disease (congenital or acquired).

  • These groups are advised to stay at home at all times, and avoid any face-to-face contact for a period of at least 12 weeks (this time period is subject to change). Visits from people who provide essential support should continue provided these people do not have symptoms and follow hand hygiene measures.

  • Consult local health authorities for more guidance as recommendations, procedures, and resources differ between countries.

  • Public Health England: guidance on shielding and protecting people defined on medical grounds as extremely vulnerable from COVID-19 external link opens in a new window


  • There is currently no vaccine available. Vaccines are in development, but it may take some time before a vaccine is available.[97][98][99] An mRNA vaccine (mRNA-1273) has been shipped to the National Institute of Allergy and Infectious Diseases for phase 1 clinical trials in the US.[100] The vaccine includes a short segment of genetic code copied from the virus. The trial started in humans on 16 March 2020. The vaccine is being fast-tracked and has skipped the animal testing stage. Clinical trials in humans have also started on an experimental adenoviral vector vaccine in China.[101]

Secondary prevention

Early recognition of new cases is the cornerstone of prevention of transmission. Immediately isolate all suspected and confirmed cases and implement recommended infection prevention and control procedures according to local protocols, including standard precautions at all times, and contact, droplet, and airborne precautions while the patient is symptomatic.[104] COVID-19 is a notifiable disease; report all suspected and confirmed cases to your local health authorities.

Detailed guidance on infection prevention and control measures are available from the World Health Organization and the Centers for Disease Control and Prevention:

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