One of the consequences of global warming is the warming of our oceans and other bodies of water. Despite water taking considerably longer to warm than the air, the waters around the world have grown increasingly warmer in recent decades. Alongside this warming comes the potential consequences of acidification, coral bleaching and species loss, just to name a few. But another consequence could be disease.
An increase in infectious diseases around the globe has been considered a potential consequence of global warming for some time. However, many scientists are hesitant to directly link any increase in disease ongoing now or potentially in the future with climate change. One of the main reasons infectious diseases are thought likely to increase with temperatures is due to increasing conditions for vectors for disease to prosper, ranging from mosquitoes to bacteria.
Increasing temperatures may be behind elevated bacteria numbers in the Baltic Sea, bacteria which lead to a number of ailments including cholera and gastroenteritis. A recent study published in the journal Nature Climate Change reported that the increasing temperatures of the Baltic Sea are likely to blame for the increase in infections, referred to as Vibrio infections, in the region of northern Europe.
The Baltic Sea “represents, to our knowledge, the fastest warming marine ecosystem examined for far anywhere on Earth,” according to the study. The Baltic Sea is said to have seen sea surface temperature rises of between 0.063 to 0.078 degrees Celsius each year between 1982 and 2010. The global sea surface temperature average increase has been 0.17 degrees Celsius per decade. To put the figures in perspective, the Baltic Sea surface temperatures would indicate a rise of between 6.3 and 7.8 degrees Celsius over a century.
The researchers studied the occurrence of reported Vibrio infections in the Baltic Sea region and compared them to sea surface temperatures in the Baltic Sea. The team determined that there is a strong correlation between the two events. Overall, each year when the sea surface temperatures were seen to rise by a degree, Vibrio infections were reportedly up by approximately 200 percent.
Vibrio infections are largely common in tropical climates due to bacterial preferences for warm and low salinity conditions. However, climate change has altered rain patterns in many regions which has increased the water to salt ratio, lowering salinity for some bodies of water. In addition, bodies of water globally are warming under the conditions. Due to this combination, it is likely that other regions will begin seeing increased cases of Vibrio infections where they are generally limited.