• Posted January 19, 2024

Climate Change Could Make Diarrheal Illness More Common

People are more prone to coming down with a common gastrointestinal infection on hot, humid days, new research shows.

The British study suggests that climate change and global warming could increase cases of diarrheal illness caused by campylobacter bacterial infections.

"This information is invaluable, as illnesses such as campylobacteriosis not only cause discomfort to individuals, but have enormous societal impacts, with people having to call in sick to work and puts extra pressure on health services across the world," said study lead author Dr. Gianni Lo Iacono.

He's a senior lecturer in biostatistics and epidemiology in the School of Veterinary Medicine at the University of Surrey.

Campylobacteriosis is typically caused by ingesting tainted food or water, and it can cause stomach pains and diarrhea lasting for days.

While most of these illnesses are mild, infections can prove fatal to small children, the frail elderly and people with compromised immune systems.

In the new study, the Surrey team analyzed data on over 1 million cases of campylobacteriosis occurring in England and Wales over a period of 20 years.

They found that when temperatures were below 46 degrees Fahrenheit, rates of campylobacteriosis illness remained steady.

But cases of infection began to rise with every 9-degree Fahrenheit rise in temperature over 46 degrees, the research showed. As well, cases began to rise when humidity reached levels between 75 and 80 percent.

As summer days lengthened to exceed 10 hours, cases of Campylobacteriosis also rose, the study showed.

The study was published Jan. 18 in the journal PLOS Computational Biology.

"What we have found is that rising temperatures, humidity and increased day length are associated with the spread of campylobacteriosis," Lo Iacono said in a university news release. "We do not fully understand why this may be. It could be that warm weather increases the survival and spread of pathogenic bacteria [so the weather causes the disease] or alternatively it could be people's behavior and how they socialize during such periods."

What is clear, however, is that "climate change not only has an environmental impact, but has the potential to negatively affect our health by aiding the spread of infectious diseases," he said.

More information

Find out more about campylobacter infections at the U.S. Centers for Disease Control and Prevention.

SOURCE: University of Surrey, news release, Jan. 18, 2024