At a glance

• Vaccine preventable – check who’s eligible
• Vaccine included on the National COVID-19 Vaccine Program – 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. Some variants can transmit more easily from person to person and spread faster. 

COVID-19 can cause mild to severe illness. Some people recover within a few days, while other people are at greater risk of getting severely unwell.

Some people may get longer-term effects following their infection. This is known as long COVID (or post-acute sequelae of COVID-19).

COVID-19 is different from seasonal flu and the common cold.

COVID-19 vaccination is the best protection against severe illness from COVID-19.

Why it matters to public health

COVID-19 affects hundreds of thousands of Australians each year.

Unlike flu infections, which usually peak in winter, COVID-19 infections can peak at any time of year. 

A rise in COVID-19 infections is known as a wave. Waves occur due to:

• new variants circulating in the community
• immunity wearing off over time
• increased socialising – for example, during holiday periods.

COVID-19 has a major impact on:

• individuals – 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. 

Because of these impacts, we:

• monitor and report on COVID-19 data
• publish guidance and advice on how to protect yourself and others from getting COVID-19
• plan for how to manage major outbreaks and pandemics.

Read more about the impacts of COVID-19 in Australia.

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 include:

• fever
• cough
• sore throat
• runny nose
• shortness of breath
• fatigue
• headache
• muscle aches and pains
• changed sense of taste or smell.

Symptoms might range from mild to severe. About 1 in 4 people infected will not have any symptoms at all.

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

Check your symptoms

Onset of symptoms

Symptoms can start from 1 to 14 days after you are exposed.

How it spreads

COVID-19 mainly spreads through droplets or smaller airborne particles from your respiratory tract which contain the virus. When you do things like talk, cough or sneeze, these droplets and particles travel through the air and land on people and surfaces. 

Other people can catch COVID-19 when these droplets or particles:

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

The risk of catching COVID-19 from an infected person is highest when you have close, face-to-face contact. But it can occur over larger distances, especially indoors. 

Infectious period

The infectious period for COVID-19 can vary, but you are generally considered infectious: 

• from up to 48 hours before your symptoms appear
• from up to 48 hours before you test positive if you have no symptoms – even if you don’t feel sick, you can still spread the virus
• until your 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. 

Prevention

Vaccination

Get vaccinated

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

Other prevention steps

You can also help protect yourself and those around you by:

• regularly washing your hands
• coughing or sneezing into your elbow or a tissue and disposing of used tissues in the bin
• avoiding touching your eyes, nose and mouth
• staying home if you are sick with cold and flu symptoms
• avoiding crowded places
• wearing a face mask if around other people, especially when indoors
• putting physical distance between yourself and others, especially when indoors
• improving ventilation, such as by opening windows.

Read about more ways to prevent COVID-19.

Priority groups and settings

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

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

• hospitals
• residential care facilities
• childcare centres
• schools.

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

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

People at greater risk of severe disease

People aged 70 years or older are most at risk of severe illness from COVID-19.

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

• with some chronic conditions
• who are immunocompromised
• with a disability
• who are pregnant.

Read more about who is at greater risk of severe disease

People at greater risk of exposure

COVID-19 is circulating in Australia, so anybody can be exposed. 

But people are at greater risk of becoming infected if they have had contact with someone who has COVID-19. This is especially true if they have had close and prolonged contact (such as living in the same house).

People who spend a lot of time around others may be more likely to be exposed to COVID-19. This includes through their jobs, living situation, or recreational activities.

Diagnosis and treatment

Your healthcare professional can diagnose COVID-19 with a polymerase chain reaction (PCR) test. The sample is usually collected from your nose or throat with a swab and sent to a laboratory for testing. 

You can also test yourself with a rapid antigen test (RAT) that detects COVID-19 – RATs are widely available from supermarkets and pharmacies.

Read more about COVID-19 tests.

You can use healthdirect’s directory to find a health service near you.

Find a health service

Most people don’t need treatment for COVID-19. You can manage mild symptoms with:

• rest
• drinking fluids
• over-the-counter medicines, such as paracetamol or ibuprofen. 

You should see your healthcare professional if you are very unwell or at greater risk of severe illness. They might prescribe antiviral medicines, if you’re eligible. 

Antibiotics are not used to treat COVID-19, because they do not work for viral infections. Taking antibiotics when you don’t need them can increase the risk of antibiotic resistance.

Read more about how to manage or treat COVID-19.

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 daily through the National Notifiable Diseases Surveillance System. 

This is part of our surveillance activities, which help us monitor case numbers around the country and understand disease patterns. 

We analyse and report on COVID-19 data through:

• the Australian respiratory surveillance report
• our data visualisation tool, where you can filter and search the latest information.

We also report data on outbreaks of COVID-19 in residential aged care homes. This includes:

• case numbers in residents and staff
• deaths
• vaccination rates
• medicines provided to residents through the Pharmaceutical Benefits Scheme.

The Australian national surveillance plan for COVID-19, influenza, and RSV guides how we collect, analyse and report on health-related data for COVID-19.

Outbreaks

State and territory health departments might respond to outbreaks of COVID-19 in some situations. This could include outbreaks:

• in high-risk settings, such as hospitals and residential aged care homes
• that involve a new variant that might be of concern to public health.

Read more about how the Australian Government defines and plans for outbreaks and pandemics.

Support

For information about COVID-19 in your state or territory, see:

• Australian Capital Territory
• New South Wales
• Northern Territory
• Queensland
• South Australia
• Tasmania
• Victoria
• Western Australia.

If you need mental health support, see a list of organisations, websites and services that offer support, counselling and information. 

Quick links

• National Guidelines for Public Health Units
• Surveillance case definition
• Laboratory case definition

Disease

Infectious agent

SARS-CoV-2 is a coronavirus belonging to the Coronaviridae family. It is an enveloped, positive-sense, single-stranded ribonucleic acid (RNA) virus.

SARS-CoV-2 emerged in late 2019. It has since genetically evolved, leading to different variants, including several variants of concern. These variants have led to changes in:

• transmissibility
• immune escape
• severity of disease.

Clinical presentation

Most COVID-19 cases present with a mild to moderate respiratory illness. About a quarter of infections are asymptomatic.[1] The symptoms of COVID-19 can vary depending on the variant.[2]

Clinical features typically include: 

• fever
• cough
• sore throat
• rhinorrhoea
• shortness of breath
• fatigue
• headache
• myalgia
• changed sense of taste or smell.

COVID-19 can cause severe disease or death, with certain people at greater risk.

Serious complications include:

• pneumonia
• acute respiratory distress
• other sequelae affecting various organ systems, such as the cardiovascular system. 

Rarely, children may develop paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2.

Reinfection with COVID-19 is common. 

This is because immunity against SARS-CoV-2, from both natural infection and vaccination, reduces over time. 

Emerging new variants of concern can also evade existing immunity. 

Both previous infection and vaccination protect against severe disease in subsequent infections.[3]

Some people may develop post-acute sequelae of COVID-19, commonly referred to as long COVID. 

Read more about the symptoms of COVID-19.

Public health importance

The World Health Organization declared COVID-19 a pandemic in March 2020. Since then, COVID-19 has caused widespread illness and death around the world. 

The COVID-19 emergency response in Australia ended in October 2023. We now manage COVID-19 like other common viral respiratory diseases, focusing on:

• reducing transmission
• preventing serious illness, hospitalisations and death. 

Vaccination, immunity from natural infection and access to antiviral treatments have reduced the impact of COVID-19. But COVID-19 continues to have significant impacts on health, the health sector and the workforce.

Long COVID is an emerging public health problem. It can limit daily activities and affect people’s ability to work.[4]

Surveillance and monitoring of COVID-19 are still important. New variants may emerge, and some of these may have the potential to cause a future pandemic. 

Read more about:

• COVID-19 circulation around the world
• the impacts of COVID-19 in Australia.

Epidemiology

Between 2020 and 2024, more than 12 million COVID-19 cases were notified in Australia. Serosurveillance studies have found that by the end of 2022, at least two-thirds of Australians had been infected.[5]

COVID-19 was the leading cause of acute respiratory infection mortality in Australia between 2022 and 2024. Most deaths were in people aged over 70 years.[6]

COVID-19 infections do not occur in a seasonal pattern, unlike influenza outbreaks, which peak between autumn and winter. 

Waves or peaks of COVID-19 infections in the community occur when:

• new variants circulate
• immunity wanes
• social mixing increases, such as during holiday periods.

For the latest information on cases of COVID-19 in Australia, see the:

• National Notifiable Diseases Surveillance System (NNDSS) data visualisation tool
• Australian respiratory surveillance reports.

Spread of infection

Transmission

COVID-19 spreads through respiratory droplets or smaller aerosolised particles released when an infected person speaks, breathes, coughs or sneezes. 

The risk of transmission is highest with close, prolonged contact. But it can occur over larger distances, especially in poorly ventilated indoor settings.[7]

Indirect transmission – such as from fomites – can also occur, but this is less likely.

Transmission is most likely to occur when an infected person has symptoms. But it can occur before symptoms develop or when the infected person is asymptomatic.[8]

Incubation period

The incubation period ranges from 1 to 14 days. 

Infectious period

The infectious period starts from about 48 hours before either:

• symptoms start
• a positive test, if asymptomatic. 

A person is considered infectious until acute symptoms have resolved (usually up to 10 days). 

People with severe disease, or who are significantly immunocompromised, may be infectious for longer.

Priority populations

People at greater risk of severe disease

Older age is the strongest risk factor for severe illness from COVID-19. People aged 70 years or older are most at risk.

COVID-19 may also pose a higher risk of severe illness for:

• people with certain chronic conditions
• people who are immunocompromised
• Aboriginal and Torres Strait Islander people
• people with disability
• pregnant people.

Read more about:

• who is at greater risk of severe disease
• measures people can take to protect themselves.

People at greater risk of exposure

A person’s risk of exposure to COVID-19 depends on the extent and nature of their interactions with other people. This can be affected by a person’s occupation, living situation and other activities. 

People who live or work in settings at increased risk of spread are at greater risk of becoming infected if there is an outbreak.

See what measures people can take to protect themselves.

Settings at increased risk of spread 

COVID-19 can spread quickly in homes, crowded places and other settings. Examples include: 

• hospitals
• residential aged care homes
• other residential facilities
• early childhood education and care centres
• schools. 

These settings should take extra precautions, including by:

• encouraging vaccination of eligible staff, residents, students and attendees
• promoting measures people can take to protect themselves
• ensuring unwell staff, students, attendees and visitors stay home.

A COVID-19 outbreak in some high-risk settings may require a public health response. 

Read more about the prevention, control and public health management of outbreaks in residential aged care homes.

Prevention

Vaccination

Vaccination remains the best way to protect against severe COVID-19.

A primary course of vaccination is recommended for:

• all Australians aged 18 years and over
• unvaccinated pregnant people
• children aged 6 months to 17 years with severe immunocompromise.

Vaccination may also be considered for other children aged 6 months to 17 years with conditions that might increase their risk of severe COVID-19.

Further COVID-19 vaccine doses are recommended every 6 to 12 months for certain groups based on age and other risk factors for severe disease.

See the Australian Immunisation Handbook for more information, including who is eligible for COVID-19 vaccinations.

Other prevention steps

Other prevention measures include:

• regularly washing hands
• maintaining physical distance from others
• wearing a mask when around others, especially when indoors
• environmental controls, such as improving indoor air quality through ventilation.

People with acute respiratory symptoms or who have COVID-19, should stay at home and avoid:

• public gatherings
• crowded settings
• using public transport
• visiting high-risk settings
• visiting people at greater risk of severe disease. 

For more information, see the Australian guidelines for the prevention and control of infection in healthcare.

Prevention among priority populations

It is particularly important for people at greater risk of severe disease to:

• stay up to date with recommended vaccinations
• take precautions to protect themselves
• avoid contact with people who have COVID-19 or acute respiratory symptoms
• discuss with their healthcare professional what they should do if they develop symptoms
• see a healthcare professional as soon as symptoms start – some people may be eligible for antiviral treatment.

Diagnosis and clinical management

Diagnosis

COVID-19 is diagnosed through either:

• nucleic acid amplification testing, most often using polymerase chain reaction (PCR) – this is done in a laboratory
• rapid antigen tests (RATs), which can be done at home – these are not as sensitive as PCR, so are more likely to miss some infections. 

These tests involve taking samples from the nose and throat.

Laboratory case definition

Clinical management

COVID-19 infections are often self-limiting, and most people will recover within 1 to 2 weeks. 

Some people may be eligible for antiviral treatment for COVID-19. These medicines work best if they are taken early, and must be started either:

• within 5 days of symptoms starting
• as soon as possible after a positive test result if asymptomatic.

Notification and reporting

Surveillance case definition

National notification and reporting

COVID-19 is a nationally notifiable disease. This means certain health professionals must report diagnoses through their relevant health authorities. Reporting requirements may vary by state or territory.

Check how to report laboratory-confirmed COVID-19 cases or related death in your state or territory:

• Australian Capital Territory
• New South Wales
• Northern Territory
• Queensland
• South Australia
• Tasmania
• Victoria
• Western Australia.

State or territory health authorities report new cases to us daily through the National Notifiable Diseases Surveillance System, as part of our surveillance activities.

We report case numbers and activity through our:

• Australian respiratory surveillance reports
• data visualisation tool, where you can filter and search the latest information.

We also track COVID-19 cases through other surveillance systems, including:

• Australian Sentinel Practice Research Network (ASPREN)
• Influenza Complications Alert Network (FluCAN)
• Short Period Incidence Study of Severe Acute Respiratory Infection (SPRINT-SARI).

This helps us to:

• identify trends in COVID-19 activity, impact and severity in Australia
• monitor virological and genetic characteristics of SARS-CoV-2
• monitor clinical characteristics of COVID-19, including severity and mortality
• assess the impact of respiratory virus control programs
• develop policies to minimise the impact of COVID-19.

We report data on vaccination rates and outbreaks of COVID-19 in residential aged care homes.

Public health response

National public health guidelines

Management of cases

The public health management of cases focuses on advice and public health messaging aimed at preventing transmission.

Specific settings – such as residential care facilities, healthcare, and other high-risk settings – might also put in place extra procedures or guidance for COVID-19 cases. This includes guidance for people who work in high-risk settings. 

In general, people with COVID-19 should not visit settings where there are people at high risk of severe disease until both:

• acute symptoms have resolved
• at least 7 days have passed since their symptoms began (or since testing positive if asymptomatic).

Public health units don’t routinely follow up single notifications. But they may do so in some situations, such as for a case with a new variant of concern.

Management of contacts

For COVID-19, contact tracing and management of contacts is only done:

• in certain special situations and high-risk settings
• for new variants of concern with characteristics that suggest the need for urgent public health action.

Outbreak response

Public health agency responses to COVID-19 cases and outbreaks depends on: 

• state or territory legislation
• local reporting requirements
• the nature of the cases or outbreak
• available resources. 

The public health response to COVID-19 outbreaks generally focuses on high-risk settings to protect people at high risk of severe disease. 

Control measures used during outbreaks may include:

• encouraging vaccination
• tailoring health education and messaging
• isolating or grouping people with COVID-19 symptoms
• increasing infection prevention and control measures, such as
  • providing hand hygiene or personal protective equipment supplies
  • increasing cleaning and disinfection
  • laundering or throwing out soiled articles.

Special situations and high-risk settings

Extra infection prevention and control actions may be required in some settings or situations if there are COVID-19 cases. These include:

• residential settings, such as aged care or disability facilities – see the guidelines for residential care facilities
• healthcare facilities – see the Australian guidelines for the prevention and control of infection in healthcare
• other settings, such as:
  • correctional facilities
  • childcare centres
  • cruise ships.

Resources

See:

• the National guideline for the prevention, control and public health management of outbreaks of acute respiratory infection in residential aged care homes
• guidance from your state and territory
• the Australian Immunisation Handbook
• the National surveillance plan for COVID-19, influenza, and RSV
• the healthdirect COVID-19 page.