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Climate change may increase risk of diarrheal disease: Study | health news


Increasing climate change – as seen in rising temperatures, day length and humidity – is linked to an increased prevalence of diarrheal illnesses, according to a study. The findings, published in the journal PLOS Computational Biology, could help predict further outbreaks of the illness, potentially leading to better preparedness among health services.

Researchers from the University of Surrey investigated the effect of local weather on the transmission of campylobacteriosis – a bacterial infection that can cause diarrhea and abdominal pain.

According to the World Health Organization, the most common cause of bacterial gastroenteritis in humans worldwide is Campylobacter infection. Infection is usually mild, but can be fatal in very young children, the elderly, and immunosuppressed individuals.

Using an innovative mathematical model, the team compared nearly 1 million cases of campylobacteriosis in England and Wales over a 20-year period and weather parameters during that time. Analysis of these data showed that the incidence of campylobacteriosis was consistent at temperatures below 8°C.

However, a sharp increase in infections (about 1 case per million) was observed for every 5 degree increase in temperature, compared to temperatures between 8 and 15 degrees Celsius. The team identified a link with humidity who also observed a higher incidence of infection when the water vapor level in the air was between 75 percent and 80 percent.

Interestingly, researchers observed a strong correlation between day length (more than 10 hours) and increased incidence of illness. This association is further strengthened if the humidity is also high.

Rainfall and wind speed were not strongly associated with the prevalence of campylobacteriosis.

“What we found is that increasing temperature, humidity and increased day length are associated with the spread of campylobacteriosis. We don’t fully understand why this might be. It could be that warmer weather increases the survival and spread of pathogenic bacteria (so the weather causes the disease) Or alternatively it could be human behavior and how they socialize during this period, says Dr Giovanni Lo Iacono, senior lecturer in biostatistics and epidemiology at the School of Veterinary Medicine at the University of Surrey, UK.

“However, what we do know is that climate change not only has environmental impacts but also has the potential to negatively impact our health by facilitating the spread of infectious diseases.”