In the age of COVID-19, it’s rather topical to talk about the spread of infectious disease. Though in recent pre-COVID-19 history, we have already seen an apparent increase in many infectious diseases such as HIV/AIDS, SARS, Ebola, hepatitis C and so on. There are numerous factors in how disease spreads including changes in demographics, socioeconomics, technological advancements and our overall environment. Climate change and how humans interact with the natural world are also significant causes in propagating and exacerbating the spread of infectious disease.

Particularly, our mistreatment of wildlife is one of the main reasons for the outbreak of COVID-19. Loss of natural habitats through persistent deforestation for example have disrupted biodiversity systems which then lead to prime conditions for mass pandemics. Various species with existing diseases are brought closer together and through wildlife trade and consumption, the cross-species jump of viruses from animal to human becomes much easier. This is without a doubt worrying trend and one that will guarantee another global pandemic if we don’t change our ways.

Climatic conditions also affect epidemic diseases and humans have know about this long before the role of infectious agents was discovered in the late 19th century. For example, knowing that mosquitoes can carry malaria and proliferate in summer and warm environments. So it’s not a surprise that climate change fundamentally affects the movement of infectious disease. As the planet gets hotter, the climate is becoming more optimal for transmission especially for mosquito-borne (and other biting insects) diseases. Wealthier Northern Hemisphere countries have generally been kept away from mosquito-borne diseases due to their economic development and colder temperatures, but climate change promises to tip the scales in the other direction. Though, a warming planet will decrease the chance of vector-borne diseases spreading, such as malaria, in places that are already relatively warm.