IMAGE: People with blood type O often get more severely ill from cholera than people of other blood types. Researchers from Washington University School of Medicine in St. Louis have found… view more
Credit: USMC/Wikimedia Commons
People with blood type O often get more severely ill from cholera than people of other blood types. New research from Washington University School of Medicine in St. Louis may explain why.
In people with blood type O, scientists found that cholera toxin hyperactivates a key signaling molecule in intestinal cells. High levels of that signaling molecule lead to excretion of electrolytes and water – in other words, diarrhea. Cholera is marked by severe diarrhea that can lead to dehydration, shock and even death.
“We have shown that blood type influences how strongly cholera toxin activates intestinal cells, leading to diarrhea,” said James Fleckenstein, MD, the study’s senior author and an associate professor of medicine and molecular microbiology.
The findings are available online in The American Journal of Tropical Medicine and Hygiene.
Cholera sickens 3 million to 5 million people around the world every year, leading to 100,000 to 120,000 deaths, many of them in the Indian subcontinent, where cholera has been endemic for centuries. Closer to home, a cholera epidemic has persisted in Haiti since 2010. The disease was brought by United Nations workers from Nepal. They had traveled to Haiti to help rebuild the country in the aftermath of a devastating earthquake.
The disease is caused by Vibrio cholerae, a bacterium that infects cells of the small intestine. Epidemiologists first noticed four decades ago that people with blood type O were more likely to be hospitalized for cholera than people of other blood types, but the reasons for the difference had never been determined.
Although the blood group antigens …