North Carolina State University researchers who recently mapped disease-causing pathogens found the world can theoretically be separated into seven regions for vectored human diseases spread by pests, such as malaria, and five regions for non-vectored diseases, such as cholera.
The researchers looked at the world's 229 countries for the presence or absence of more than 300 diseases -- 93 vectored diseases and 208 non-vectored diseases.
"This is about more than just the movement of people -- climate, history and geography all seem to be important factors in how diseases survive and thrive across the globe," Michael Just, a doctoral student in plant and microbial biology and lead researcher, said. "Understanding that not all pathogens are everywhere could have consequences for public health and the global society as a whole."
The study showed that not every region is contiguous, meaning that colonization is just one of a variety of factors, along with climate and socio-political status, which can potentially affect the prevalence of disease in a certain area.
"Researchers have mapped humans, animals and plants and their movement and evolution across the globe, but the things that live on or with us -- pests and pathogens, for example -- have been largely ignored," Just said. "This study is a good first step in examining the relationship between people and their pathogens, which could have important human health implications."