COVID-19 is disease caused by a coronavirus (SARS-CoV2), which until late 2019 had not previously been identified in humans. It is a highly contagious respiratory illness which has spread rapidly around the world. On 11 March 2020, the World Health Organisation declared it a pandemic
COVID-19 is an upper and lower respiratory tract infection, which can range from mild illness to pneumonia. While most people will recover, in severe cases pneumonia develops and it can be fatal. There is currently no vaccine or specific treatment for COVID-19. Social distancing, good hygiene, contact tracing and testing are the best preventative measures we currently have to manage the disease.
Key disease information
Coronaviruses have crown-like spikes protruding from their surface. The word ‘corona’ is Latin for crown– hence these viruses are called coronaviruses. The coronavirus responsible for causing COVID-19 is called SARS-CoV2.
The initial symptoms of COVID-19 are very similar to that of colds and influenza. They include:
- loss of smell or taste
- sore throat
People who have symptoms, even mild should get tested. It is also possible to have no symptoms, however it is not known yet how often this happens. For this reason social distancing and good hygiene are important practices to incorporate into your daily life.
COVID-19, SARS (sudden acute respiratory syndrome) and MERS (Middle Eastern respiratory syndrome) are all respiratory syndromes caused by coronaviruses. In addition, these coronaviruses were initially found only in animals, but have mutated so that they can now infect humans. Because they have not previously been known to infect humans, people usually do not have immunity to these coronaviruses.
However, the coronavirus causing each disease is different. In addition, the ease of transmission and severity of disease is also different.
SARS and MERS are associated with higher death rates than COVID-19. However because COVID-19 is more infectious, it spreads more easily and therefore has infected vastly greater numbers of people and caused more deaths.
SARS predominantly infected people in Hong Kong and did not spread rapidly around the globe like COVID-19. There have been no recorded cases of SARS for more than a decade. While MERS is still a concern in the Middle East, it also has not spread to many other areas.
Coronavirus spreads from person to person mainly through respiratory droplets produced when a person coughs or sneezes. These droplets can land on the persons nose or mouth and infect that person. (6) The droplets are relatively heavy, so do not travel far, but will land on objects or surfaces such as door handles or tables. If another person touches these objects and then touches their mouth or face they can come into contact with the virus.
This is why social distancing, hand washing, covering your mouth when coughing/sneezing and staying way from others if you feel unwell – are so important. As they help stop the spread of this disease.
There is currently no specific treatment for COVID-19. Doctors will treat the symptoms. While in most cases the symptoms will resolve on their own, the disease can rapidly progress, so it is important to seek medical advice. People who have serious disease with complications will be treated in hospital.
When a person sneezes or coughs they generate droplets. These droplets are too large to stay in the air for long and settle on surrounding surfaces. How long they remain there will depend on the type of surface and also the surrounding temperature and humidity. Studies have shown that COVID-19 virus can live for up to 72 hours on plastic and stainless steel, less than 4 hours on copper and less than 24 hours on cardboard.
Coronaviruses can be killed with use of common household disinfectants. Clean your hands with an alcohol-based hand sanitiser or wash them well with soap and water. It is important to avoid touching your face, especially your mouth or nose.
In Australia people who have recently returned from overseas and anyone who has been in close contact with someone who has been diagnosed with COVID-19 are most at risk of developing the disease.
The people who are at greater risk of developing a serious disease after being infected with COVID-19 virus are:
- elderly people
- people with a compromised immune system
- people with chronic medical conditions
- Aboriginal and Torres Strait Islander people
Many different research groups around the world are working on developing a vaccine – as many as 115! Whether or not there will ever be a vaccine which is effective and safe is still to be determined. In the meantime, it is important that we all do our part to prevent the transmission of the virus by following guidance from the Australian health authorities.
A pandemic is an outbreak of an infectious disease that spreads across the globe affecting many countries on different continents. For a new virus to have pandemic potential it must meet three criteria:
- humans have little or no pre-existing immunity to the virus
- the virus causes disease in humans
the virus can spread easily from human to human
COVID 19 was declared a pandemic on 11 March 2020. (3)
Epidemics are also outbreaks of infectious disease that affect a large number of people – but the disease remains mainly in a specific region. Examples of recent epidemics are Ebola in Western Africa and Zika virus.
Researchers are investigating whether someone can get COVID-19 more than once. Until such time as more is known, continue to take steps to protect yourself and others from COVID-19.
Sources & Citations
- Queensland Heath. Coronavirus (COVID-19). https://www.health.qld.gov.au/news-events/news/novel-coronavirus-covid-19-sars-queensland-australia-how-to-understand-protect-prevent-spread-symptoms-treatment (Date accessed 27 May 2020)
- Australian Health Department. COVID-19 – Frequently asked questions.https://www.health.gov.au/sites/default/files/documents/2020/04/coronavirus-covid-19-frequently-asked-questions_10.pdf (Date accessed 27 May 2020)
- NSW Health Department. COVID-19 – Frequently asked questions. https://www.health.nsw.gov.au/Infectious/covid-19/Pages/frequently-asked-questions.aspx#1-2 (Date accessed 27 May 2020)
- World Health Organisation. Q&A on coronavirus (COVID-19). https://www.who.int/emergencies/diseases/novel-coronavirus-2019/question-and-answers-hub/q-a-detail/q-a-coronaviruses (Date accessed 27 May 2020)
- Hewings-Martin Y. How do SARS and MERS compare with COVID-19? Medical News Today. April 10, 2020. https://www.medicalnewstoday.com/articles/how-do-sars-and-mers-compare-with-covid-19#Coronaviruses-past-and-present (Date accessed 27 May 2020)
- Centers for Disease Control and Prevention (CDC). Coronavirus Disease 2019 (COVID-19) Frequently Asked Questions. https://www.cdc.gov/coronavirus/2019-ncov/faq.html (Date accessed 27 May 2020)
- New Zealand Ministry of Health. COVID-19: Questions and Answers. https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-health-advice-general-public/covid-19-questions-and-answers#surfaces (Date accessed 27 May 2020)
- Le, TT et al. The COVID-19 vaccine development landscape. Nature Rev Drug Discovery 2020;19:304-6.
MAT-AU-2000008 Date of preparation June 2020Show All