Albendazole Found to Improve Physical Fitness in Poor Women Farmers with Hookworm

A recent study conducted by researchers at Yale University and a nonprofit company called InnovationsCZ has found that albendazole, a low-cost anti-hookworm drug, helped improve the physical fitness of impoverished women farmers with hookworm in the Democratic Republic of Congo (DRC).

It is estimated that 4.7 billion individuals worldwide reside in regions that are at increased risk of exposure to parasitic worms, or helminths, that are transmitted via soil to humans. Furthermore, the World Health Organization estimates that 1.5 billion individuals worldwide are infected by these parasites.

The most common helminth species responsible for infections are roundworms, whipworms, and hookworms. These infections are known to plague the poorest and most deprived communities, and they have significant impacts on the health of those infected.

“Much of hookworm’s health impact is mediated through intestinal hemorrhage caused by adult parasites, which attach to the gut mucosa and feed on blood from lacerated capillaries,” the study authors write. “Intestinal blood loss leads to—or exacerbates—iron deficiency (ID) and eventually leads to ID anemia (IDA).”

For the double-blind, prospective, randomized study, published in an online issue of The American Journal of Tropical Medicine and Hygiene, investigators sought to determine if a single-dose treatment of albendazole could improve the physical fitness of women farmers with hookworm living in the DRC. Albendazole is a broad-spectrum, synthetic benzimidazole-derivative anthelmintic, according to the National Institute of Health’s PubChem. The drug interferes with the reproduction and survival of parasitic worms by hindering the formation of microtubules from tubulin. Doing this weakens glucose uptake, which, in turn, kills the worm.

A secondary focus of the study was to determine if women of child-bearing age should be included in mass drug treatment campaigns which target helminth infections. Poor women of child-bearing age are thought to be particularly vulnerable to hookworm infection; they experience blood loss during menstruation and when pregnant, through demands of the fetus, according to the press release. Hookworms feed on blood and are known to cause chronic anemia. Hookworms have also been linked to inflammation of the intestines, according to the investigators, as well as impairment of natural digestive enzymes which could result in malnutrition and other issues.

Participants of the study were randomized into either a treatment group (n = 125) or a placebo group (n = 125). Those in the treatment group were given 400 mg of albendazole, while those participants in the placebo group received an identical tablet without therapeutic benefit; all field personnel were blinded to who was enrolled in which group.

The investigators conducted an exercise tolerance test before, and 7 months after participants received the treatment to measure the effectiveness of albendazole on improving physical capacity.

According to the study results, those women who received the 400 mg dose of albendazole experienced significant improvement in their overall physical fitness. Furthermore, the authors noted that post-treatment, infected participants’ heart rates dropped by about 10 beats per minute when performing a simple exercise test.

“We think the lower heart rates we observed were also a good indication of an increased capacity for the physical demands of farm labor,” co-author Michael Cappello, MD, professor of pediatrics, microbial pathogenesis, and public health at the Yale School of Medicine, explained in a recent statement. “It’s all the more impressive because the women who tested positive for infection had a relatively low level of hookworms and were not more anemic than those who were uninfected.”

He added that the fact that those who were infected with hookworm had “relatively light infections” prior to treatment, and, as such, the other effects of hookworm infection (inflammation, impaired digestion) could also have serious health implications and these effects can still be triggered by low parasitic levels in the gut.

"There is strong evidence that children with moderate to heavy hookworm infections derive significant physical and developmental gains from effective treatment," Dr. Cappello said. "Far less is known about the benefits of broadly treating people like the women who participated in this study, who have a lighter burden of parasites."