Global burden of foodborne parasites remains high

A new World Health Organization (WHO) analysis estimates that approximately 171 million illnesses worldwide were attributable to foodborne transmission of invasive parasites, highlighting the significant burden these often-overlooked diseases continue to place on global health.

This research, which includes contributions from Texas A&M College of Veterinary Medicine and Biomedical Sciences (VMBS) professor Dr. Christine Budke, updates global estimates for 14 foodborne parasitic diseases. Although progress has been made over the past decade in decreasing their prevalence, the findings show these illnesses continue to disproportionately affect vulnerable populations around the world.

“The WHO periodically updates these estimates to help governments and public health organizations understand which diseases have the greatest health and socioeconomic impacts, allowing them to make more informed decisions about where limited resources can have the greatest effect,” said Budke, who specializes in zoonotic tapeworm diseases and previously contributed to the WHO’s original foodborne disease burden estimates.

Measuring more than illness

The study is part of the WHO Foodborne Disease Burden Epidemiology Reference Group (FERG), an international initiative tasked with measuring the global impact of foodborne diseases.

In her role within the international effort, Budke worked with researchers at the University of Montreal to update estimates for neurocysticercosis, a disease caused by the larval stage of the pork tapeworm that can infect the brain and is a leading cause of epilepsy in many parts of the world.

Instead of simply counting infections or deaths, the researchers evaluated disease burden using disability-adjusted life years (DALYs), a metric that combines years of life lost due to premature death and years of healthy life lost due to disability or illness into a single measure that allows health officials to compare diseases across populations.

“Disability-adjusted life years allow us to evaluate not only how many people become ill or die but also the severity and duration of illness,” Budke said. “Those estimates help provide a much more complete picture of how diseases affect populations and give decision-makers better information when determining where resources are needed most.”

The updated analysis incorporates more than a decade of additional research and new information about how these diseases affect patients, allowing researchers to refine the earlier WHO estimates.

“As more information becomes available, we can improve these estimates,” Budke said. “Ultimately, people around the world will use these numbers when making decisions about resource allocation for control programs and health services, so it’s important that they are as accurate as possible.”

Diseases that haven’t disappeared

Although improvements in sanitation, hygiene, and education have reduced the burden of some foodborne parasitic diseases, Budke said they remain an important public health concern, particularly in low-resource regions where surveillance and control programs are limited.

Many foodborne parasitic diseases fall under the WHO’s category of neglected tropical diseases — illnesses that disproportionately affect the world’s poorest and most vulnerable populations while receiving relatively little research funding and public attention.

“They definitely haven’t gone away,” Budke said. “Many parts of the world continue to struggle with foodborne diseases, and we cannot turn a blind eye and forget about them because once you do that, it’s likely they’re going to rear their ugly head again.”

Beyond their health effects, these diseases can also perpetuate cycles of poverty. People living with multiple neglected tropical diseases may struggle to work, care for their families, or escape financial hardship, while the communities most affected often lack the resources and political influence needed to advocate for greater investment in prevention and treatment.

Budke said that while foodborne parasites occasionally capture public attention during outbreaks, many neglected parasitic diseases continue affecting vulnerable communities long after the headlines fade.

“We tend to gravitate toward the new headline diseases,” Budke said. “Meanwhile, these neglected diseases continue impacting communities, affecting people’s ability to work, support their families, and thrive.”

Turning data into action

While updated estimates represent an important step forward, Budke said significant knowledge gaps remain.

For neurocysticercosis, researchers are still working to understand the full range of neurological complications beyond epilepsy, including severe headaches and other long-term effects. In many countries where the disease is most common, diagnosing patients remains difficult because advanced imaging technologies such as CT scans are often unavailable.

Despite those challenges, refining these estimates remains essential to helping countries make informed public health decisions.

“The goal of the WHO is to provide countries with the best available information,” Budke said. “Hopefully, they can use these data to make informed decisions that are best for their populations.”

For Budke, the updated estimates serve as a reminder that foodborne parasitic diseases remain a global health challenge deserving continued attention and investment.

“Foodborne parasitic diseases are still causing serious problems for people around the world,” she said. “We can’t afford to forget about them.”