Risk factors for more serious illness

Not being vaccinated increases your risk of serious illness from COVID-19. There are also a number of treatments, illnesses, conditions and other factors that increase the risk of serious illness.

Who is at greater risk of severe illness

If you are unvaccinated, you are at greatest risk of severe illness from COVID-19.

Being vaccinated reduces the risk of getting infected. If you do get infected, being vaccinated reduces the risk of:

  • developing severe illness

  • hospitalisation

  • death.

Talk to your doctor about getting vaccinated, or book an appointment.

Other factors than can increase the risk of severe illness

Your risk can also be increased by:

  • certain treatments

  • particular illnesses and conditions

  • your age, especially if you are over 70 years old

  • your environment

  • smoking

  • being pregnant

  • being male.

If you have any concerns, talk to your doctor.

Treatments that increase the risk of severe illness

You are at greater risk of severe illness if you are undertaking:

  • immune suppressive therapy

  • chemotherapy

  • radiotherapy

  • immunotherapy

  • targeted anti-cancer therapy

  • bone marrow transplant.

Illnesses and conditions that increase the risk of severe illness

You are at greater risk of severe illness if you have:

  • blood cancer (such as leukaemia, lymphoma or myelodysplastic syndrome)

  • non-haematological cancer (diagnosed in the past 5 years)

  • childhood cancer

  • chronic inflammatory condition requiring medical treatment

  • primary or acquired immunodeficiency

  • chronic renal (kidney) failure

  • chronic lung disease

  • heart disease (coronary heart disease or failure)

  • diabetes

  • chronic liver disease

  • neurological conditions such as stroke or dementia

  • severe mental health condition

  • severe obesity (BMI ≥ 40 kg/m2)

  • poorly controlled blood pressure.

Advice for specific communities and groups

Aboriginal and Torres Strait Islander people

Aboriginal and Torres Strait Islander people and those living in remote communities are at greater risk from COVID-19. Find out how you can reduce the risk, where you can get help and how you can keep your community safe.

People with disability

People with disability face a greater risk of serious illness from COVID-19. Find out what you can do to reduce your risk or that of someone you care for.

Older people

Older people, especially those aged over 70, are at greater risk of developing serious illness from COVID-19. The immune system weakens with age and becomes more vulnerable to infections of all types. Find out more about keeping yourself, or someone you care for, safe.

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