Heavy rainfall has battered Eastern Australia leaving many people in a battle to navigate the hazards of returning to a home that has been flooded

Precautions need to be taken as the mop-up begins. There are dangers, both seen and unseen, which don’t cease once the rain stops and the water begins to drain away.  

People can easily underestimate the dangers they are returning to, but a simple understanding of the nature of floodwater could save a life and prevent illness.

1. Why is mould taking hold in flood damaged homes?

Weeks of rain have left high levels of moisture in the air and as the floodwaters recede dangerous levels of mould is taking hold in homes. Mould thrives in wet environments so water damaged buildings, which cannot be dried quickly, will subsequently see mould.

Many people are unaware of how devastating mould can be to their health.  When moisture is trapped, mould can take hold both in the timber in a home as well as the paper lining in gyprock. When the fungus takes hold, it can eat away timber and cause dangerous structural damage especially if the home is unable to dry quickly enough.  

Mould only needs a damp, moist environment, and organic material to establish itself.  Rugs, carpets, and big pieces of furniture that cannot be dried quickly need to be removed. If lots of mould is visible, then expert help and the insurance policy need to be checked. Experts will use chemicals that will remove the mould without spreading the spores through the air.

2. Why are flood damaged properties seeing mushrooms inside their homes?

If mushrooms spring up inside a home, then there could be a very serious problem that is a consequence of saturated timbers.

Poor air ventilation and timbers left very wet for too long are a sign of a significant moisture problem. If mushrooms are seen then mushroom spores may cause asthma, respiratory conditions, allergic reactions, immune disorders, and infection of the sinuses.

Quick removal of wet materials and drying out buildings to reduce moisture and humidity in flooded houses would prevent the growth of mould and mushrooms and improve air quality.

Both white mould mushrooms and black mould mushrooms should never be eaten!

3. What are the dangers of wading through floodwater?

As people get back into their homes to check out the damage they may need to wade through pooled and still flood water.  By doing this they are putting themselves at potential risk of contracting a waterborne disease.

It is not just water they are wading through as raw sewage would be the most probable contaminant. Floodwaters can overwhelm treatment plants, septic tanks and drainage systems causing sewage to enter the floodwater.

Poo, loving parasites thrive and contaminate untreated water. The increase in rodent activity also increases the risk of disease that spreads through the urine of infected animals and can enter a human’s body if swallowed or entering through a cut.

Besides parasites and poo, toxic chemical hazards can be present. Petrol and diesel can spill out of vehicles, industrial facilities, petrol stations and other sources. These hazardous chemicals pose health risks to the public and clean-up workers.

 A spark may ignite any oil or petrol on the water’s surface adding to dangers of hydrocarbon contaminated floodwaters.

4. Which water-borne diseases will be present in floodwater?

Common contaminants found in flood water are the poo loving parasites Giardia, Cryptosporidium and the bacteria salmonella can E. coli these all cause different forms of gastroenteritis if contaminated water is swallowed.  People are also vulnerable if they neglect frequently and thoroughly washing their hands.

Leptospirosis is a disease that spreads through the urine of infected animals including rats, mice, marsupials, pigs, and cattle. Leptospira bacteria can survive in soil as well as floodwater contaminated for months.

The bacteria enter the body through broken skin or the lining of the nose, mouth, or eyes.  In some cases, it can be fatal.

Initial symptoms are flu-like giving a fever, headache chills vomiting and conjunctivitis. If severe disease develops due to delays in treatment or misdiagnosis of the disease could risk severe complications including, pulmonary haemorrhage, acute liver, or renal failure, and jaundice. In some cases, it can be fatal.

Lurking in flood water can be Aeromonas, this is another bacterium that causes skin and soft tissue infection causing acute watery diarrhoea, abdominal cramps, nausea, vomiting and fever. Cellulitis is a deep infection of the skin which can be caught, this usually affects arms and legs but can also develop around the eyes, mouth, anus, or belly.

5. How can you protect yourself in floods?

\When returning to clean up a property from flood damage

  • Cover any cuts and abrasions with waterproof dressings.
  • Wear suitable protective clothing including boots, gloves, and eye protection
  • Control rodents by removing any food sources and rubbish that are close to the house
  • Wash hands thoroughly with soap/disinfectant.
  • Avoid putting your hands in your mouth or near your eyes

6. What about driving in floodwater?

It is not worth risking your safety or the safety of the people who will rescue you if you drive through floodwater. Conditions in a flood can change rapidly and it is often difficult to tell how deep the water is and the speed of the current.

As the visibility of the water is hindered, concealed hazards could trap and injure you. The quality of the road may be severely degraded from heavy rain and obscure the depth of any potholes. Washouts could have occurred with obscured floating objects and fallen power lines, snakes or even crocodiles being washed into the water.

It is best to avoid floodwater but if essential and presumed safe to do so, then driving at a slow steady speed is best. Flood conditions can change rapidly, and it can be difficult to tell the speed of the current. If the vehicle you are in becomes stranded best to leave it and move to higher ground in case the water rises any further.

7. Why are people worried about Japanese Encephalitis?

Additional wetlands created by the floods are thought to have attracted water birds from Asia as they are known to follow flooded watercourses. Those birds carrying the Japanese Encephalitis virus may have been bitten by mosquitoes and are now spreading the disease to humans. The flooding and the stagnant pools left behind are perfect breeding conditions for these mosquitoes.

Most people who are infected only develop mild flu-like symptoms. However, the virus spreads to the brain quickly and can cause complications like tremors, seizures, and paralysis. People who develop serious symptoms may die and there is no cure. Some vaccines can ward off the infection, but Australia only has a limited stockpile.

As Australia grapples with its first major outbreak of Japanese encephalitis a public health alert has been issued and insect repellent has been flying off the supermarket and chemist’s shelves. In some areas, insect repellent is in shortage supply!

8. Which other insects are hazards after the flooding?

If the insects have not died in the floodwaters, the rain then helps the insects to live longer.  As people brace themselves for an insect explosion, on the coast there is expected to be an increase in numbers of paralysis tick. Humans can get allergic reactions such as swelling of the throat and breathing difficulties or collapse. If an animal has been bitten by a paralysis tick, then like humans if medical attention is sought straight away there is a good chance of recovery.

As insect numbers are set to explode, biting buffalo flies may also blow in from Queensland, which are irritating to humans and animals. As food and garbage build up as people clear their houses from the flooding this becomes a breeding ground for flies. Flies carry disease but their burst of numbers also extends to dragonflies and spiders which feed on the abundance of prey.

For those homes that were not flooded, they have seen an invasion of small insects like ants or termites as they seek a drier environment from the waterlogged ground.

9. Does the accumulation of flood garbage bring any other unwanted guests?

Rats and mice carry diseases and unless waste food and garbage are covered and removed, they will quickly establish themselves in new settings. Many of these rodents are carriers of illnesses that may be passed on to humans even if there is no direct human contact as disease-transmitting microorganisms are found in rodent urine and droppings. Leading to an expansion of rodent-borne infectious illnesses such as leptospirosis and salmonellosis. If a mouse has salmonellosis the droppings can remain active for up approximately 150 days after the infection has occurred.

 More problems, after a home is flooded, can be brought on by insects crawling into spaces and basements leading to more severe pest problems and termite infestation.  Early remedy of treating moisture issues must be paramount in the aftermath of a flood.

Rats and mice, as well as snakes and spiders, may be stranded in a house shed of garden so care must be taken when re-entering a flooded home.

10. How do you practice safe cleaning when returning home after flooding?

There are many risks for homeowners and volunteers when helping in the clean-up.

  • Throw away any food and bottled water that has been in floodwater as well as any food that has not been refrigerated for more than two hours
  • Items that cannot be washed or cleaned with bleach need to be thrown out. Mattresses, pillows, stuffed toys, carpets, carpet underlay
  • Items that cannot be washed or cleaned with bleach need to be thrown out. Mattresses, pillows, stuffed toys, carpets, carpet underlay
  • Use diluted bleach to clean the dirt off floors, stores, sinks, countertops, cutlery, crockery, and tools.
  • Bury any faecal matter quickly.
  • Wash hands before eating or drinking 
  • Wear appropriate clothes like closed in shoes or boots and gloves when in contact with floodwater
  • Cover cuts or sores with waterproof dressings