Find out more about the science behind coronavirus (COVID-19).

Coronavirus (COVID-19) is a new disease that the world is still learning about. New research is happening all the time so we can understand more about the disease, including the long-term effects.

Your questions answered

What are the long-term effects of the coronavirus (COVID-19)?

Coronavirus (COVID-19) only emerged in late 2019, so the world is still learning about the virus. It may take years before we fully understand its long-term effects. There is limited research investigating the long-term effects of coronavirus (COVID-19), and the studies vary in quality.

Recent research suggests that between 10% to 87% of people who have recovered from coronavirus (COVID-19) experience ongoing symptoms.  

As of September 2020, more than 60 symptoms of coronavirus (COVID-19) have been reported. The most common long-term symptoms are:

  • fatigue
  • shortness of breath
  • chest pain or discomfort
  • inability to concentrate
  • reduced ability to smell.  

Coronavirus (COVID-19) may cause damage and inflammation to the lungs, heart, kidneys and brain. This may affect these organs in the long-term.  

This is one of the reasons why it is important to protect yourself and others by washing your hands regularly, wearing a face mask and maintaining physical distance of at least 1.5 metres. See how to stay safe and well page for more information.

What is the latest information on immunity to coronavirus (COVID-19)?

When infected with a virus, it is common for people’s bodies to develop defences that give the body immunity that can protect them from getting the same virus again. As coronavirus (COVID-19) is a new virus, we don’t yet understand how long such immunity will last.

Some coronavirus (COVID-19) research shows that immunity levels may begin to decrease a few weeks after recovery, and people who experience milder symptoms may develop less immunity.  

As of September 2020, only two instances of reinfection have been reported globally. In both cases, tests found that the first and second infections were separate occurrences and not a continuation of the same infection.  

With over 33 million reported coronavirus (COVID-19) infections around the world so far, just two known cases of reinfection are not alarming at this stage. With more testing, monitoring and research ramped up worldwide, this is subject to change.

How is coronavirus (COVID-19) transmitted?

As coronavirus (COVID-19) is a new virus, new research is emerging from scientists regularly. Currently, the World Health Organization suggests that coronavirus (COVID-19) can be transmitted by contact with droplets, airborne aerosols and contaminated surfaces. Airborne aerosols are tiny particles that float in the air. This understanding may change as more research emerges and we learn more about coronavirus (COVID-19).

Droplet transmission

A person can be infected with coronavirus (COVID-19) by touching respiratory droplets like saliva or tears from an infected person. These are spread through coughing, sneezing, kissing, talking or singing.  

These droplets can enter your mouth, nose or eyes and cause infection. This can happen by having close face-to-face contact, being within 1.5 metres of someone with coronavirus (COVID-19), or by touching a contaminated surface before touching your face.

Airborne transmission

Saliva or tears from an infected person can stay in the air after they cough, sneeze, talk or even sing. This means that coronavirus (COVID-19) can be spread through these tiny infectious particles suspended in the air.  

Sometimes, the virus can remain in the air for some time in settings such as in indoor spaces with poor ventilation.  

Contaminated surfaces transmission

Coronavirus (COVID-19) can spread when secretions or droplets from an infected person touch the surfaces of objects. The virus can live on surfaces for hours or days, depending on conditions such as temperature, humidity, type of surface, and how much of the virus is present.

If you touch an infected surface, you could become infected by touching your nose, mouth or eyes. You could also spread the virus from one surface to another and infect other people.

Can coronavirus (COVID-19) be transmitted by people with immunity?

As of September 2020, there have been no recorded transmissions from people who have recovered from coronavirus (COVID-19).

Resources/further reading

Our information draws on recent research published:

Carfì, A., Bernabei, R. and Landi, F. (2020). Persistent Symptoms in Patients After Acute COVID-19. JAMA. [online] Available at: https://jamanetwork.com/journals/jama/fullarticle/2768351 [Accessed 27 Sep. 2020].

Couzin-Frankel, J. (2020). From ‘brain fog’ to heart damage, COVID-19’s lingering problems alarm scientists. [online] Science | AAAS. Available at: https://www.sciencemag.org/news/2020/07/brain-fog-heart-damage-covid-19-s-lingering-problems-alarm-scientists [Accessed 27 Sep. 2020].

COVID-19 Body Politic Slack Group (2020). Report: What Does COVID-19 Recovery Actually Look Like? [online] Patient Led Research. Available at: https://patientresearchcovid19.com/research/report-1/ [Accessed 27 Sep. 2020].

Tenforde, M.W. (2020). Symptom Duration and Risk Factors for Delayed Return to Usual Health Among Outpatients with COVID-19 in a Multistate Health Care Systems Network — United States, March–June 2020. MMWR. Morbidity and Mortality Weekly Report, [online] 69. Available at: https://www.cdc.gov/mmwr/volumes/69/wr/mm6930e1.htm?s_cid=mm6930e1_w.