Using stool samples from Viking latrines, researchers at the University of Copenhagen have genetically mapped one of the oldest human parasites -- the whipworm. The mapping reflects the parasite's global spread and its interaction with human beings, a delicate relationship that can make us healthier and ill.

 

Using fossilized eggs in up to 2500-year-old feces from Viking settlements in Denmark and other countries, researchers at the University of Copenhagen's Department of Plant and Environmental Sciences and the Wellcome Sanger Institute (UK) have made the largest and most in-depth genetic analysis of one of the oldest parasites found in humans -- the whipworm.

 

The study, published in Nature Communications, presents completely new knowledge about the parasite's development and prehistoric dispersal. This knowledge can be applied in efforts to prevent the parasite's drug resistance and its future spread.

 

The study suggests that human and parasite have developed a delicate interaction over thousands of years, whereby the parasite tries to stay "under the radar" not to be repelled, which allows it more time to infect new people. From other studies, it is known that the whipworm stimulates the human immune system and the gut microbiome, to the mutual benefit of both host and parasite.

 

While whipworm (Trichuris trichiura) is now rare in industrialized countries, and most often only causes minor problems among healthy individuals, the parasite is estimated to affect 500 million people in developing countries.

 

"In people who are malnourished or have impaired immune systems, whipworm can lead to serious illness. Our mapping of the whipworm and its genetic development makes it easier to design more effective anti-worm drugs that can be used to prevent the spread of this parasite in the world's poorest regions," says Professor Christian Kapel of UCPH's Department of Plant and Environmental Sciences.