HEALTH WATCH: Preventing intestinal worms

By Dr Cory Couillard

Up to two thirds of children are at risk of intestinal parasitic worms. The most common worms include roundworms, hookworms and whipworms.

The highest prevalence occurs where there is inadequate sanitation, low levels of education, and lack of access to health care services.

Infestations can impair physical growth, brain development and are major causes of nutrient deficiencies such as iron deficiency anaemia. Hookworm-induced iron de?ciency anaemia has been associated with decreased physical activity, worker productivity and adverse pregnancy outcomes in adults.

Roundworms, hookworms and whipworms have all been associated with impaired development, poor school performance and absenteeism in school-age children. Infestation is associated with malnutrition through appetite suppression, increased nutrient loss, and decreased nutrient absorption and utilization.

Roundworms get their nutrition from the contents of one’s digestive tract. They have been associated with impaired fat digestion, temporary lactose intolerance, and reduced vitamin absorption, especially vitamin A.

Adequate vitamin A intake is essential to human health. Dietary vitamin A, in the form of beta-carotene is a strong antioxidant that helps the body fight off infection and sustains the strength one’s immune system.

Infected people excrete the eggs of the worms in their faeces, which then contaminate the soil. Walking barefoot, trying to grow food, and allowing children to play in contaminated areas are important mechanisms of infestation.

Other mechanisms of intestinal worm infestation include :

consumption of food and water contaminated with human or animal faeces;
eating raw or undercooked meats such as pork, beef or chicken;
poor hygiene habits such as infrequent washing or bathing;
not washing one’s hands before eating, preparing food or after using the bathroom.

Symptoms of intestinal worms include diarrhoea, abdominal pain, weakness and generally not feeling well. Hookworms cause chronic intestinal blood loss that result in anaemia. The most common symptoms of anaemia include fatigue and loss of energy, shortness of breath, headache and dizziness.

People with iron deficiency anaemia can also experience symptoms of soreness of the mouth and experience cracks at the corners, an upward curvature of the fingernails and a strange hunger for substances such as paper, ice or dirt. Eating contaminated dirt can cause further infestation.

The control of intestinal worms is often based on anthelminthic drug treatment, improved sanitation and health education. The medicine kills and facilitates the expulsion of worms from the body. Benzimidazoles (albendazole and mebendazole) are the most common deworming drugs used to treat infestations in children.

Research has shown that deworming during pregnancy (after the first trimester) and iron supplementation significantly reduces maternal anaemia, increases the weight of the newborn and reduces infant mortality rates.

Despite significant gains, challenges remain that include lack of financial resources and competing priorities that have prevented the scaling-up of deworming activities.

Practicing good hygiene habits is imperative to the prevention of intestinal worms. Eating a healthy diet with fresh fruits and vegetables as well as drinking purified water will naturally boost the strength of one’s immune system and prevent intestinal worms.

Dr Cory Couillard is an international health columnist working in collaboration with the World Health Organization's goals of disease prevention and global health care education. Views do not necessarily reflect endorsement.