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Health risks after a flood or cyclone

Warning:

For emergency help from police, fire or ambulance services, call triple zero (000). For urgent help during any other natural disaster, such as floods, storms and tsunamis, contact your state or territory emergency service (SES) on 132 500.

Key facts

  • Floods and cyclones are natural disasters that can happen anywhere in Australia.
  • The official tropical cyclone season in the Australian region runs from November to April each year.
  • Health risks after floods and cyclones include injuries and infections.
  • Before evacuating, make sure you have enough of your important medicines and an emergency kit ready.
  • If you need help during a natural disaster, call triple zero (000) or your state or territory emergency service (SES) on 132 500.

What are floods and cyclones?

Floods and cyclones are types of natural disasters that happen in Australia. They can cause injuries and infections and may prevent you from accessing your medicines.

What is a flood?

A flood is an overflow of water onto dry land. Flooding can be dangerous and create serious health risks.

Types of flooding include:

  • river or creek flooding ­— when rivers or creeks overflow onto land that is usually dry after heavy rain
  • coastal flooding ­— caused by high tides in coastal areas
  • flash flooding — caused by short, intense bursts of rainfall

What is a cyclone?

A cyclone is a large, powerful storm that forms over warm ocean water. It spins in a circular pattern around a calm centre, called the eye.

Cyclones can cause damage from:

  • extreme winds
  • heavy rainfall
  • storm surges

The official tropical cyclone season in the Australian region runs from November to April. Cyclones happen most often in Western Australia, the Northern Territory and Queensland.

Cyclones are called hurricanes or typhoons in other parts of the world.

What are the health risks after floods and cyclones?

Floods and cyclones can cause many health risks, including:

Read more about supporting your child through a natural disaster.

Contaminated floodwater

Floodwater and mud can contain germs that increase your chance of:

Food, drinks or medicines that have come into contact with contaminated floodwater can also cause illness.

Tips to help you stay safe:

  • Do not walk or drive through floodwater or mud. It may be contaminated with sewage and debris. Your chance of infection is higher if you have a chronic condition, alcohol dependency or regularly take steroid medicines.
  • Avoid contact with floodwater if you have cuts, grazes or open wounds.
  • Wash your hands with soap and water or use alcohol-based hand sanitiser after touching floodwater, mud or flood-affected material.
  • Throw away any food that has touched floodwater.
  • Check with your local council if the local water supply is safe. If you are unsure, boil drinking water before using it.

Loss of medicines

During a natural disaster, it is important to keep taking your medications to protect your health. If you need to evacuate your home and it is safe to do so, pack your:

  • medicines
  • prescriptions
  • healthcare cards
  • medical records.

If possible, prepare an emergency kit in advance (Opens in new tab) so you are ready.

Tips for managing your medicines in an emergency:

  • Keep refrigerated medicines cold with ice packs or cold bags. Some medicines must not be frozen, so speak with your doctor or pharmacist if you're unsure.
  • If your medicine needs to be stored in a fridge but has been left out, ask a pharmacist if it needs to be replaced.
  • Throw away any medicines that have come into contact with floodwater. Your pharmacist can advise you on safe disposal (Opens in new tab).
  • If you lose important medicines or need replacements, ask your doctor to send a prescription to your nearest pharmacy. If you can't reach them in an emergency, a pharmacist may be able to help.
  • If you're in a declared disaster area, you can access Medicare-subsidised doctor services through telehealth.

Injuries

Extreme weather such as floods and cyclones can create dangerous conditions, such as:

  • slippery surfaces
  • objects underwater
  • hidden debris
  • fallen trees
  • flying objects

These hazards can cause serious injury or death.

Tips to help you stay safe:

  • Use a walking pole, such as a broom handle or stick, to help you move safely.
  • If you get a cut, graze or other wound, rinse it with clean water and cover it with a dressing.
  • See your doctor or a local health clinic if a cut or wound becomes dirty, red, sore or if it is deep.

Ask your doctor if you need a tetanus booster. This is especially important if your wound is dirty or deep or if your last tetanus booster was more than 5 years ago.

Read more about first aid basics.

Warning:

Call triple zero (000) and ask for an ambulance if someone loses consciousness (even briefly), is unable to get up or has severe pain. If triple zero (000) does not work on your mobile phone, dial 112.

Animal bites

Watch for snakes or spiders in your home or among debris after a flood or cyclone. Some bites may be life-threatening, such as those from brown snakes or funnel-web spiders.

If a potentially life-threatening snake or spider bites you:

  • Keep still and call triple zero (000) and ask for an ambulance. If calling triple zero (000) does not work on your mobile phone, dial 112.
  • Do NOT wash, clean, suck or cut the bite area.
  • Apply a firm bandage along the full length of the affected arm or leg and immobilise the limb with a splint.
  • If you do not have a bandage, cover the area with a clean, dry dressing or use clothing.
  • Mark on the bandage the time of the bite and when the bandage was put on.
  • If the bite is not on the limb, apply firm pressure directly over the bite site.
  • Lie still and wait for the ambulance.

If you live in far north Queensland or areas known to have crocodiles, be aware that they may appear in unexpected places.

Tips to help you stay safe:

  • Be cautious around all waterways, not just those with crocodile warning signs.
  • Avoid using canoes and kayaks.
  • Stand back from the water's edge.
  • Never provoke, harass or feed crocodiles.

Report crocodile sightings (Opens in new tab) to the Department of Environment, Science and Innovation using the Qwildlife app or online (Opens in new tab). You can also call 1300 130 372 and select option 1.

Warning:

If you or someone you know is in immediate danger, call triple zero (000) and ask for an ambulance.

Mosquito-borne infections

Floodwater and pooled rainwater create ideal breeding conditions for mosquitoes. This increases the chance of mosquito-borne diseases.

Tips to help you stay safe:

  • Use insect repellents containing DEET or picaridin.
  • Use mosquito nets at night.
  • Use fly spray, mosquito coils or plug-in repellents.
  • Wear long, loose light-coloured clothing.

To reduce mosquitoes around your home:

  • Repair or install insect screens.
  • Drain water from yards and workplaces where it has collected.
  • Empty containers after rain, including buckets, tyres, birdbaths and pot plant holders.
  • Check water tank screens and replace them if needed.

Carbon monoxide poisoning

During power outages, people may use petrol-powered generators or pumps. These can cause carbon monoxide poisoning (a dangerous gas you cannot see or smell) if used indoors or in poorly ventilated spaces.

Tips to help you stay safe:

  • Always use generators and pumps outdoors in well-ventilated areas.
  • Service them according to the manufacturer's instructions.

How can I stay safe while cleaning up after a flood?

Cleaning up after a flood can be physically demanding and sometimes dangerous. Taking simple precautions can help protect your health and safety. Here are some examples:

  • Take your time when cleaning up. Look after your health — take frequent breaks, protect yourself from sunburn and drink plenty of water.
  • Seek advice from your local council about safely cleaning up asbestos and sanitising rainwater tanks.
  • Do not use swimming pools contaminated by floodwater until the water has been tested and the pool has been thoroughly cleaned.
  • Be aware of fallen electricity wires, especially near or under water. Report fallen wires immediately.
  • Take care when using chainsaws or other equipment to clear vegetation. Wear protective clothing and do not use equipment if it's wet.
  • Ask for help if the clean-up is too much for you to manage. Contact your state or territory emergency service (SES) on 132 500 for assistance.

Read more about staying safe during floods and cyclones.

Resources and support

For emergency help in floods and storms, contact your state or territory emergency service (SES) on 132 500. You can also call if there is:

  • serious damage to your home
  • property at risk of flooding
  • a tree that has fallen on your car or home

SES volunteers respond to many types of emergencies and provide support during times of crisis. If you're in an emergency, contact the SES in your state or territory:

For advice about floods and cyclones, visit your state or territory authority website:

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.

Languages other than English

The Victorian Government provides fact sheets (Opens in new tab) with important information about what to do after a flood in a range of community languages.

St John Ambulance Australia (Opens in new tab) has detailed first aid fact sheets in English and other community languages.

Last reviewed: February 2026

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