RESEARCHERS predict that climate change will increase the Earth’s mean temperature, cause temperature fluctuations, and increase the frequency and intensity of extreme weather events. How these changes will affect infectious disease and impact human healthTrusted Source, agricultureTrusted Source, and wildlife remains to be seen.
Research shows that temperature variance can modify host-pathogen dynamics. One study found that daily temperature fluctuations increase malaria transmission, and anotherTrusted Source suggested that short-term temperature fluctuations led to reduced transmission.
Further research shows that how extreme heat events affect host-pathogen dynamics may also depend on the magnitude, duration, and intensity of the heatwave.
For example, one studyTrusted Source investigating a parasitoid-insect interaction found that a heatwave increase of 5°C increased parasitoid size while a 10°C increase reduced parasitoid growth.
Knowing how host-pathogen dynamics respond to temperature variation could help researchers and policymakers alike prepare for the effects of climate change.
In a recent study, researchers led by Dr. Pepijn Luijckx, assistant professor in parasite biology at Trinity College Dublin, Ireland, investigated the effects of different temperatures on the host-pathogen dynamics.
They found that temperature variation alters pathogen-host interactions in complex ways that may affect disease dynamics in an unanticipated manner.
“Here, we show that temperature variation with each of the traits we measured […] responds in a unique way to different types of temperature variation,” Dr. Luijckx told Medical News Today. “Given that our mathematical models for disease spread rely on numerous variables, and our results show that each of these may respond in a unique way to both changes in temperature mean and variance, predicting how global warming may alter diseases may be incredibly complex.”
For the study, the researchers examined the effects of different temperatures on small crustaceans called Daphnia magnaTrusted Source alongside its gut parasite, Ordospora colligata.
Researchers frequently use Daphnia in ecological model system research, and Ordospora transmission is representative of classical environmental transmission, similar to viral infections such as SARS-CoV-2.
They then subjected the crustaceans alongside their parasites and a placebo infection as a control to three temperature regimes for 27 days:
