Giardiasis can often be prevented by practising good hygiene and taking commonsense precautions.
Wash your hands
The most effective way to prevent giardiasis is to wash your hands regularly, particularly:
- after going to the toilet
- after changing a nappy
- before handling and eating food
Wash your hands with soap and water. You should also encourage your children to wash their hands regularly.
Avoid drinking untreated water from rivers and lakes.
Swimming pools, paddling pools and water parks can sometimes become contaminated, particularly if they're used by younger children. Giardia parasites can survive in chlorinated water, so you shouldn't assume chlorinated water is safe.
If you're going camping, it's recommended you boil water before drinking it.
If you're travelling to countries where giardiasis is widespread and sanitation is poor, only drink bottled water. Make sure the bottle is properly sealed before using it. You should also use bottled water when brushing your teeth.
Also avoid eating raw fruit and vegetables as they may have been handled by someone with giardiasis. Read about food and water abroad for more information and advice.
Places where giardiasis is widespread include:
- sub-Saharan Africa – all the countries south of the Sahara desert, such as South Africa, Gambia and Kenya
- south and southeast Asia, particularly India and Nepal
- Central America
- South America
- the countries of the former Yugoslavia (Croatia, Serbia, Montenegro, Slovenia, Macedonia, and Bosnia and Herzegovina)
Preventing the spread of infection
If you're diagnosed with giardiasis (or if you have diarrhoea), it's important to take precautions to prevent other members of your household becoming infected. You should:
- wash your hands regularly
- not cook or handle food that will be eaten by other members of your household
- avoid sharing utensils or towels
It's recommended you stay away from work or college and avoid swimming pools until you've been completely free from symptoms for 48 hours. Your child should also stay away from school or nursery until they've been completely free from symptoms for 48 hours.
Read more about preventing the spread of germs.
If you have frequent anal sex, make sure you wash your hands after handling a used condom. Kissing or licking also increases the risk of infection and should be avoided.