Giardiasis holiday misery continues
A study into the long-term effects of giardiasis, a parasitic disease, and one of the most common causes of gastrointestinal infections in travellers, found that many travellers were still suffering years later. Giardiasis is a zoonotic disease – passed from animals to humans – caused by a flagellate protozoan, giardia lamblia. Encased in a hard, shell-like cyst, the organism is found in the digestive tracts of humans and many animals. People can only become infected with giardia by swallowing the parasite. Anything that comes into contact with faeces from infected humans or animals can become infected, although it is usually spread by touching contaminated surfaces, drinking water or ice made from water containing the parasite, accidentally swallowing infected water while swimming, or eating uncooked food that contains the parasite.
Scientists in Canada looked at 1,252 people who were infected with giardiasis during an outbreak in 2004, and when the researchers interviewed the people three years later, they found that 39 per cent suffered from Irritable Bowel Syndrome (IBS) and 30 per cent suffered from chronic fatigue. In 2010, the incidence of IBS in the group had decreased from 39 per cent to 32 per cent, and those still reporting chronic fatigue problems fell to 15 per cent. The scientists concluded that not only was exposure to the parasite a ‘significant risk factor’ for persistent IBS and fatigue, but it was also worse for older people, with age increasing the risk of ongoing chronic fatigue.
Other investigations into the longer term effects of travellers’ illnesses have shown similar results. For example, a study published in 2013 that collected data on over 42,000 people who had been treated for illness following overseas travel found that more than 40 per cent of travellers who reported gastrointestinal symptoms lasting more than two weeks suffered from chronic fatigue or IBS. The same study showed that giardia was the most common cause of gastrointestinal illnesses; and that most cases of giardiasis occurred in South and Central Asia countries, particularly India.