Coming in the wake of the widespread flood crisis is a less dramatic but equally dangerous threat. Mould can have devastating health effects if allowed to reproduce uncontrollably in moist areas after the water has gone down.
Part of the fungi group of organisms, mould is always around us, inside and outside. The problem is when growing conditions become perfect for exponential spread. Most mould species are toxic to humans at high concentration.
The main drivers of mould are inadequate ventilation, humidity and moisture. Mould can be visible, on the surface of walls, ceilings and carpets, or hidden inside walls and furnishings. Many health issues come from the spores, which mould releases as part of its life cycle.

Health effects of exposure to spores include a runny or blocked nose, eye irritation and sometimes wheezing.
For those at risk of asthma, mould exposure can bring on a full-blown attack. In rare cases, mould can infect human bodies, usually in the lungs.
Those at greatest risk are people with pre-existing breathing conditions, weakened immune systems or chronic lung disease.
What can you do about it?
If possible, let air get at wherever the mould is. Open windows and use exhaust fans.
Reduce humidity if you can (fish tanks, indoor plants and unflued gas heaters all make humidity worse).
If your house has been seriously flooded, wall claddings may need to be removed so the house frame can dry.
Water leaks need to be repaired wherever they occur and rising damp needs to be blocked with already affected material disposed of.
Bleach discolours mould, making it harder to see, but doesn’t necessarily destroy it. Consider non-toxic, more effective alternatives such as hydrogen peroxide, vinegar, baking soda, essential oils and lemon juice.