Can we eradicate infectious diseases?
Imagine living in a world where anytime someone was infected by parasites it would make headline news – globally.
This was the case for a member of the British royal family; only he died a few hundred years ago! Indeed scientists discovered that this king was suffering from a roundworm infection at the time of his demise. Likely the worms didn’t kill the king, but they must have affected his health and quality of life.
Today, there are almost 900 million people with roundworm infections around the world. These people are seldom in the news, if ever, because they live in the shadow of poverty and neglect – neglected by their own governments and leaders and, not too long ago, neglected by large sectors of the scientific community and international donors.
But things are changing. There’s a global movement to control not only roundworm infections but also many of the tropical neglected diseases (NTDs) afflicting the poorest of the poor around the world, in particular children and pregnant women.
“Perhaps in a future not too far away, NTDs will be controlled or eradicated, and every time someone would be diagnosed with any of these infections, they will be on the evening news,” says Ana Sanchez, a researcher at Brock University. A fantasy perhaps, she says, but a worthy goal. Sanchez studies infectious diseases, specifically parasitic diseases that target vulnerable populations – the poor and youth in developing countries.
“Epilepsy that’s caused by tapeworms, for example, is twice as high in developing countries compared to high-income nations, and can reach 30 percent in some towns in Latin America,” says Sanchez.
Intestinal roundworms, transmitted by contaminated soil due to nonexistent sanitary facilities, are another parasite that can wreak havoc. These roundworms steal nutrients from children and pregnant women, cause anemia, and alter immune defenses in a way that makes their human hosts more susceptible to other infections.
Sanchez aims to understand how parasites and humans relate. And with this knowledge, she hopes to help individuals and entire communities reduce and even prevent the occurrence of parasitic diseases.
“Part of my research is to estimate the prevalence of parasitic diseases in children. We measure children’s growth, ask about their habits, as well as their school and housing environments,” says Sanchez. “Then we try to find a connection between these factors and the parasites they harbour.”
She and her research team use this information to create a profile for each person, and study how the parasites and the individuals are affected by external factors. They also create profiles for the towns and communities to help policy-makers better prioritize resources and reduce other precipitating factors that cause infection.
“We study how parasites respond to treatment, and look at the optimal dose according to age,” she says.
“Our research is showing that while the deworming is working, it’s definitely not as good as it could be,” says Sanchez. “Just by increasing the dose to twice a year, you could reduce the number of people infected by more than half.”
Part of her role as a researcher, as Sanchez sees it, is trying to empower parents and broader community to keep their schools clean. “Better, cleaner schools reduce the prevalence of parasites,” she says. In fact, she’d like to see vaccines delivered by schools in local communities, and decentralized from the government.
“The treatment for these parasites is quite safe,” says Sanchez. “There are very few adverse effects, which is why schools could administer the vaccine.”
Through her work, Sanchez hopes that parasitic plagues may one day be as far removed from reality in developing nations as they are here in Canada.