Climate change cannot be blamed for the emergence of COVID-19 directly, but scientists have plenty of evidence for how its environmental degradation encourages infectious diseases. In the past, wars and poverty and unsanitary conditions have been the key vectors for spreading disease. In the 21st century, the ecological degradation caused by climate change has led to increased contact between wildlife and humans, leading to more risk of zoonoses, diseases transmissable from living animals to humans.
It is estimated that 60% of emerging infectious diseases are caused by zoonotic pathogens. Of those zoonoses, almost 72% are caused by pathogens of wildlife origin.
“A global outbreak of sever acute respiratory syndrome (SARS) started in Asia and caused more than 700 deaths and 8,000 cases in 37 countries during 2002 and 2003. In March 2003, the World Health Organization issued a first global alert. The causative agent, identified in April 2003, is a coronavirus. It was found in civets sold in the food markets in Guangdong in southern China, where the epidemic started. Later, the virus was also found in Chinese bats. The hypothesis is that the virus “jumped” from animals to humans.”