A study conducted on mollusk fossils revealed that a type of parasitic infection could spread among humans due to the effects of climate change, Science Daily reported.
For their research, paleobiologists from the University of Missouri turned to the remains of mollusks that existed during the Holocene Epoch, a period which began almost 12,000 years ago.
They discovered that during that time, sea level rise lead to an increase in the number of flatworms or parasitic trematodes. These parasites cling on to mollusks and other organisms that live in estuarine areas, or bodies of water where freshwater and saltwater meet.
The researchers were able to study presence of the trematodes on the fossils due to the evidence they left on the once living organisms.
"Because they have soft bodies, trematodes do not leave body fossils," John Huntley, an assistant professor at the university and co-author of the study said in a statement according to MU News.
"However, infected clam shells develop oval-shape pits where the clam grew around the parasite in order to keep it out; the prevalence of these pits and their makeup provide clues to how the clams adapted to fight trematodes," he added.
Comparing their findings with information collected on Earth's environmental conditions, Huntley warned that the parasitic infections on mollusks can happen again due to increasing water levels caused by climate change.
In addition, Huntley noted that although trematodes will directly affect mollusks, the infection could also transfer to humans due to the natural food chain.
When infected, humans could experience inflammations in the liver, brain and gall bladder. Based on a report from the World Health Organization, around 56 million people are afflicted with parasitic infections caused by eating food items contaminated by trematodes.
"When compared to documented rises in sea level more than 9,300 years ago, we found that we currently are creating conditions for an increase in trematodes in present-day estuarine environments," he explained.
"This could have harmful implications for both animal and human health, including many of the world's fisheries," Huntley added.
Huntley and his team predicted that if sea levels continue to rise due to climate change, the number of parasitic infection cases among human populations will also increase in the near future.
