What is COVID-19?
If you develop symptoms such as severe shortness of breath or chest pain, call triple zero (000) immediately. Tell the call handler and the paramedics on arrival if you have COVID-19.
What is the coronavirus and COVID-19?
Coronaviruses are a large family of viruses that cause respiratory infections.
The coronavirus that originated in Wuhan, China, was a new strain of coronavirus that hadn’t been detected in people before.
The virus was initially known as the ‘Novel Coronavirus (nCoV-2019)’, but it’s now officially named Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).
The infectious disease caused by this virus is called COVID-19.
What is a COVID-19 variant?
A variant is when a virus mutates slightly, or changes. Variants frequently happen in viruses, but sometimes a variant can make the virus spread more easily, can make symptoms worse (or better) or reduce the effectiveness of treatments and vaccines.
The original COVID-19 virus has had many variants since it was first discovered, with some being labelled by the World Health Organization (WHO) as a ‘variant of concern’. A variant of concern is one that may change how the pandemic behaves, so the WHO pays close attention to it.
These variants (named after letters of the Greek alphabet) include Alpha, Beta, Gamma, Delta and most recently Omicron.
How is COVID-19 spread?
COVID-19 is spread between people through:
- direct contact such as by touching each other
- indirect contact such as by touching contaminated objects or surfaces. When people with the virus sneeze, cough or touch surfaces, they may leave infected droplets on these surfaces. The virus can survive on these surfaces for several hours to a few days
- close contact through the mouth or nose secretions of infected people
- breathing in air when close to an infected person who is exhaling droplets that contain the virus
- certain medical procedures
- aerosol transmission, where infected droplets stay suspended in the air for long periods of time, especially where an indoor environment has little fresh air. This includes places where people talk, shout or sing — for example, at restaurants, nightclubs, places of worship and workplaces
- fans and air-conditioners which circulate the infected droplets (especially if they recirculate the air)
How severe is COVID-19?
Most people infected with COVID-19 experience mild or moderate symptoms — fever and cough are the most commonly reported symptoms. However, in more severe cases breathing difficulties can develop into pneumonia.
Children may experience milder symptoms than adults.
People at most risk of serious infection include:
- people 70 years of age or older
- people with chronic medical conditions or compromised immune systems
- Aboriginal and Torres Strait Islander peoples
- pregnant women
If you have any COVID-19 symptoms and need to visit your doctor, it is very important that you call before visiting, to describe your symptoms.
If you have severe difficulty breathing, call triple zero (000) immediately and tell the call handler and the paramedics you might have COVID-19.
CHECK YOUR SYMPTOMS — Use the COVID-19 Symptom and Antiviral Eligibility Checker to find out if you need medical help.
Related topics

Symptoms and when to get help
Learn to recognise mild, moderate and severe symptoms of COVID-19, and when to seek medical advice from your GP or another healthcare professional.

How to avoid COVID
There are many ways to reduce your risk of COVID-19, including physical distancing, wearing a mask, hand washing and getting vaccinated.
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Last reviewed: February 2022