Climate change would also have an impact on the occurrence of zoonosis in Africa. In a study published on April 28, 2022, a team of researchers from Georgetown University in the United States of America indicates that climate change could cause 15,000 crossings of viruses from one animal species to another by 2070. Humans are not immune; as such transfers often allow the virus to adapt to the human body, causing zoonotic diseases.
In Africa, the ravages of climate change can also be seen in biological terms. In a study published on April 28, 2022, a team of researchers from Georgetown University in Washington DC in the United States of America indicates that there will be 15,000 passages of viruses from one animal species to another by 2070, due to climate change. “This is one aspect of global warming that is unstoppable. It’s happening even in the most optimistic scenarios of the Intergovernmental Panel on Climate Change (IPCC),” says Colin Carlson, co-author of the study.
The study modeled possible range shifts for more than 3,300 mammal species as a result of climate change. According to the study, bats would be among the most involved in viral transmission, because they fly far and wide and their highly robust immune systems allow them to carry many viruses without getting sick. “The Covid-19 pandemic likely originated from a bat virus that was transmitted to a wild animal sold in Chinese markets, possibly the pangolin. Ebola and HIV are other viruses that have passed from one mammal to another before mutating sufficiently to infect humans,” the study said.
Thus, outside of Africa, the Georgetown University study indicates that most transmissions of viruses from one species to another occur in Asia and South America, because of their rich biodiversity.
The climate factor of zoonotic diseases
In a previous study published by the Institut national de la santé publique du Québec (INSPQ), the contributions of current and projected climate change to the increase in zoonotic diseases are demonstrated. There is the creation of climatic conditions favorable to the proliferation of pathogens, i.e. organisms that can cause parasitic or microbial diseases.
The modification of the habitat, of the hibernation period, of the life span as well as of the reproduction conditions of the reservoir species by the increases of temperature, precipitations and humidity. Also, the increase in outdoor activities, such as hiking and camping, because the summer season has become hotter and longer, puts people at greater risk of infection.