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What is giardiasis?

Giardiasis is an infection, specifically of the digestive system. Symptoms generally appear after at least a week of contracting the infection. It is characterised by diarrhoea, with abdominal cramps, bloating, high-smelling stools and wind, and burping. Appetite loss, nausea, vomiting, indigestion, fatigue, and fever may also occur. Giardia affects absorption of fats in the intestine and this can lead to weight loss. However, some infected people do not show any symptoms.

Can I get treatment for Giardiasis?

If you or someone you have been travelling with has been diagnosed with Giardiasis then The Online Clinic can prescribe an appropriate medication. Simply complete the quick online consultation form.

What causes giardiasis?

Giardiasis is caused by a parasite named Giardia intestinalis or Gardia lamblia that lives in the intestines (gut) of humans and other animals. The parasite lives in two forms in the intestine, as trophozoites and cysts. Trophozoites are active and transform in the small intestine into inactive cysts. Both forms are passed in the faeces, but the cysts are the infective form. Once swallowed, cysts are activated by the acid in the stomach to become trophozoites.

Who is at risk of giardiasis?

The Giardia parasite is transmitted through drinking water, eating food, contact with soil, or swimming in water that has been contaminated with faeces of infected humans and animals. It can also be contracted by contact with infected people or from objects that they have touched. Person-to-person contact includes those practicing anal and oral sex.

Giardia infection often occurs when travelling abroad. It is found worldwide, particularly where there is limited access to clean water and good sanitation. Such areas include sub-Saharan Africa, south Asia, Central and South America, Russia, and some of Eastern Europe. Anyone can be affected but young children along with their parents (due to nappy changing and toileting) are most vulnerable.

In England and Wales, approximately 3,500 cases are reported each year but the exact number of cases is probably higher as many people remain undiagnosed. About 25% of people are infected while abroad, although symptoms mostly appear when they get home. Single cases of Giardia are unusual. Several people in the home or a nursery/school may contract Gardia, while shared drinking sources such as wells are often the source of larger outbreaks.

How can I reduce the risk of giardiasis?

The key to Giardiasis prevention and spread is good hygiene.

Whether in this country or abroad, do not drink directly from streams, rivers or lakes. Drink bottled water or boil and filter water first, and do not take ice in drinks or brush your teeth in tap water. Especially when abroad, wash fruit and vegetables in clean water and peel them before eating, eat food that is freshly prepared and well-cooked through. Thoroughly wash hands after using the bathroom, changing nappies or toileting children, and before preparing food. Note that swimming pools and communal water bathing may be contaminated with infectious parasites, even those that are chlorinated.

For those who are infected, additional to the above recommendations, a few precautions can help prevent the spread of giardiasis. People who are infected should wash hands thoroughly on a regular basis, and should not prepare food for others, or share cutlery or towels. They should not visit swimming pools or attend nurseries/schools until symptom free for about two days.

When should a doctor be contacted?

Particularly after having been abroad, adults should contact a doctor if suffering diarrhoea, abdominal cramps, bloating, and nausea for over one week, while children should be seen after having diarrhoea for a few days or if they have had more than six bouts of diarrhoea in 24 hours or if they appear dehydrated.

How is giardiasis diagnosed?

Giardiasis can be diagnosed from a stool sample. Stools can be tested for Giardia proteins or examined under a microscope for the presence of the two forms of the parasite. Other procedures involve examining fluid from the duodenum (part of the gut) and biopsy of the small intestine.

How is giardiasis treated?

Antibiotics, usually Metronidazole or Tinidazole, are effective in the treatment of Giardiasis. The entire course of treatment must be taken to ensure symptoms do not return and all the parasites are dead. Additionally, as a precaution, other people living in your home may also be advised to take this medicine as they may have been infected.