Heat waves can reduce the body’s immune response to flu, according to new research in mice at the University of Tokyo. The results have implications for how climate change may affect the future of vaccinations and nutrition.

Climate change is predicted to reduce crop yields and nutritional value, as well as widen the ranges of disease-spreading insects. However, the effects of heat waves on immunity to influenza had not been studied before.

University of Tokyo Associate Professor Takeshi Ichinohe and third-year doctoral student Miyu Moriyama investigated how high temperatures affect mice infected with influenza virus.

Flu in a heat wave

“Flu is a winter-season disease. I think this is why no one else has studied how high temperatures affect flu,” said Ichinohe.

The influenza virus survives better in dry, cold air, so it usually infects more people in winter. However, Ichinohe is interested in how the body responds after infection.

The researchers housed healthy, young adult female mice at either refrigerator-cold temperature (4 degrees Celsius or 39.2 degrees Fahrenheit), room temperature (22 C or 71.6 F), or heat wave temperature (36 C or 96.8 F).

Source: Heat waves, food insecurity due to climate change may weaken immune systems