COVID-19

At a glance

Vaccine preventable – check who’s eligible
Nationally notifiable disease

About COVID-19

COVID-19 is a highly contagious respiratory infection.

It is caused by a virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

There are many subtypes, or variants, of SARS-CoV-2. Variants are monitored for their ability to spread more easily or cause more severe illness.

COVID-19 symptoms can be mild to severe. Most people recover within a few days, but some people are at greater risk of getting severely unwell.

Some people, including those with mild or no symptoms, might have longer-term effects after having COVID-19. This is known as long COVID (or post-acute sequelae of COVID-19).

Why it matters to public health

COVID-19 continues to circulate and cause serious illness in Australia.

Each year in Australia, COVID-19 causes around:

2,000 to 5,000 deaths
110,000 hospitalisations.

The number of COVID-19 infections in the community can go up and down in ‘waves’. COVID-19 waves don’t follow a regular seasonal pattern. They can happen when:

new variants circulate in the community
immunity wears off over time.

COVID-19 can have a major impact on:

people – through illness and complications leading to hospitalisation and death
our health system – through added demand on healthcare professionals, clinics and hospitals
businesses and our economy – through missed school and work and reduced productivity.

Symptoms

If you’re looking for advice about your own health or treatment options, see healthdirect or speak with a qualified healthcare professional. Our role is to provide public health advice – information and guidance that helps prevent disease, protect communities and improve wellbeing at a population level.

Common symptoms of COVID-19 include:

Less common symptoms include:

changes in smell or taste
nausea
vomiting
diarrhoea
shortness of breath.

Symptoms can range from mild to severe. They usually resolve within days to weeks, but the cough can last longer.

About 1 in 4 people with COVID-19 don’t have any symptoms.

healthdirect’s symptom checker can help you decide whether to see a doctor.

Check your symptoms

Onset of symptoms

Symptoms usually start 3 to 4 days after infection, but this can range from 2 to 14 days.

How it spreads

COVID-19 mainly spreads through droplets or smaller airborne particles from an infected person’s respiratory tract. When people talk, cough or sneeze, these travel through the air and land on people and surfaces.

COVID-19 can spread to others when these droplets or particles:

come into contact with their mouth, nose or eyes
are breathed in
land on surfaces or objects which people touch and then touch their mouth, nose or eyes.

The risk of COVID-19 spreading is highest when there is close, face-to-face contact. But it can spread over larger distances, especially indoors.

People can be infected more than once.

Infectious period

The length of time people with COVID-19 can infect others varies. But people are usually considered infectious:

from 48 hours before symptoms appear
from 48 hours before the first positive test, if there are no symptoms
until symptoms are gone, which can be up to 10 days.

Some people may be infectious for longer, such as those who are severely ill or have a weakened immune system.

People with COVID-19 are usually most infectious just before their symptoms start and in the first 3 days of having symptoms.

People can still spread the virus, even if they have no symptoms.

Prevention

Vaccination

Get vaccinated

The best way to protect yourself is to get vaccinated – the COVID-19 vaccine reduces your risk of severe illness, hospitalisation and death.

Other prevention steps

You can help protect yourself and others by:

staying at home if you have symptoms
improving ventilation, such as by opening windows
putting physical distance between yourself and others, especially when indoors
wearing a face mask when around others, especially when indoors
regularly washing your hands
coughing or sneezing into your elbow or a tissue and disposing of used tissues in the bin (then washing your hands afterwards).

Read about more ways to prevent the spread of COVID-19 and other respiratory viruses.

Priority groups and settings

Some people are at greater risk of getting COVID-19 or getting very sick from it.

COVID-19 can spread quickly in crowded places and some settings, such as:

hospitals
residential care facilities – including aged care or disability care homes
childcare centres
schools.

If you are at greater risk of severe disease, it is especially important to:

get your COVID-19 vaccination
take steps to protect yourself
avoid crowded places, if you can
avoid contact with anybody with COVID-19 or who has symptoms
talk to a healthcare professional as soon as symptoms start – they might prescribe antiviral medicines, if you are eligible.

People at greater risk of severe disease

Older people are most at risk of severe illness from COVID-19.

COVID-19 also poses a greater risk of severe illness for people who are:

living with some chronic conditions
immunocompromised
living with a disability
pregnant
Aboriginal and Torres Strait Islander people.

People at greater risk of exposure

Anybody who spends time around other people can be exposed to COVID-19. But people who have a lot of contact with others might be more likely to be exposed. This includes through their jobs, living situation, or recreational activities.

Diagnosis and treatment

COVID-19 is usually diagnosed through laboratory testing of a sample collected from the nose or throat with a swab.

Rapid antigen tests that can be done at home are also widely available from supermarkets and pharmacies.

Surveillance and reporting

COVID-19 is a nationally notifiable disease – these are diseases that present a risk to public health.

Health authorities in each state and territory report new laboratory confirmed cases to us through the National Notifiable Diseases Surveillance System.

COVID-19 data is also collected through other surveillance systems, guided by the Australian National Surveillance Plan for COVID-19, Influenza, and RSV.

We analyse and report on COVID-19 data through: