By Sean Chen
A recent Stanford study led by infectious diseases instructor at the Stanford School of Medicine John Openshaw has uncovered high levels of tapeworm infections among elementary schoolers in the western portion of China’s Sichuan province.
The researchers highlighted that the infections can lead to cognitive defects, ultimately compromising children’s access to educational opportunities and in reducing their chances of breaching poverty cycles.
Openshaw’s research team tested fifth and sixth grade students — all at boarding schools in the Himalayan region of Sichuan — for tapeworm. The researchers identified antibodies for neurocysticercosis in up to 22 percent of children tested. This rate surpassed those of adults living in the surrounding area.
“While historically researchers have studied adults with this disease, the burden on kids and what that burden means for affected countries in terms of lost productivity and lost income in unknown,” Openshaw said in an interview with Stanford News. “We hope our work will fuel interest in figuring that out.”
Taenia solium, the specimen studied by Openshaw and his team, is a tapeworm whose larvae can be found in undercooked pork but can ultimately cause harm to the brain. Once the tapeworm has been ingested, it lays eggs which embed in feces and potentially contaminate the environment.
The tapeworm eggs can be transmitted through physical contact, food and even clothing. When consumed, the eggs hatch tapeworms capable of reaching the brain and can result in symptoms such as seizures, vision problems, confusion and hallucinations.
According to the World Health Organization, the tapeworm infection, also known as neurocysticercosis, is one of the leading causes of deaths from food-borne diseases and accounts for 30 percent of epilepsy cases in areas where the parasite is endemic. Seven million people are estimated to be affected in China alone.
The team is assisting in efforts to eliminate the disease in the region. The researchers plan to distribute tapeworm medication in schools and increase accessibility to hand-washing stations and soap. The researchers are also working to integrate proper hand hygiene practices into the schools.
Openshaw says that unhygienic conditions at the visited boarding schools exacerbate the spread of the disease. Many children wear the same one or two pairs of clothes to school and sometimes sleep on shared beds. In addition, school bathrooms are generally pit latrines and tap water and soap are not easily accessible.
“All you need is a couple people with gastrointestinal tapeworms and poor hygiene,” Openshaw said.
The paper documenting these findings is co-authored by comparative medicine associate professor Stephen Felt, Stanford’s Rural Education Action Program project manager for health and nutrition Alexis Medina, international agricultural policy professor Scott Rozelle and professor of medicine Stephen Luby, among others.
Community awareness of the causes and treatments of the disease is also crucial, according to Openshaw. One third of parents surveyed by the team in the area said they believe that intestinal worms had no adverse effects, and 19 percent thought that decreased activity, drinking hot water or eating spicy foods amount to effective treatments.
“The tools to eradicate this disease are available,” Openshaw said. “We hope that as the true burden of this disease on children becomes clearer, governments and nongovernmental actors will commit more resources.”
Contact Sean Chen at kxsean ‘at’ stanford.edu.