A deadly amoeba which targets the human brain is spreading because of climate change, experts say. Naegleria fowleri amoeba is responsible for primary amoebic meningoencephalitis (PAM).
It was previously confined to the southern United States and Central America but is spreading north as the climate warms up.
Scientists at the University of Mount Union and the University of Kansas are urging people and medics to remain vigilant.
Naegleria fowleri is commonly found in freshwater lakes and rivers, but can be found in tap water.
Experts fear that the warming temperatures have created an environment more conducive to the amoeba's spread.
Scientists state in their report: "Increased incidence of this rare, deadly, and often misdiagnosed illness in northern states causes concern that N fowleri is expanding northward due to climate change, posing a greater threat to human health in new regions where PAM has not yet been documented."