Abstract
Background Infectious diseases are a major burden on human population, especially in low- and middle-income countries. The increase in the rate of emergence of infectious outbreaks necessitates a better understanding of the worldwide distribution of diseases through space and time.
Methods We analyze 100 years of records of diseases occurrence worldwide. We use a graph-theoretical approach to characterize the worldwide structure of human infectious diseases, and its dynamics over the Twentieth Century.
Findings Since the 1960s, there is a clear homogenizing of human pathogens worldwide, with most diseases expanding their geographical area. The occurrence network of human pathogens becomes markedly more connected, and less modular.
Interpretation Human infectious diseases are steadily expanding their ranges since the 1960s, and disease occurrence has become more homogenized at a global scale. Our findings emphasize the need for international collaboration in designing policies for the prevention of outbreaks.
Funding T.P. is funded by a FRQNT-PBEE post-doctoral fellowship, and through a Marsden grant from the Royal Academy of Sciences of New-Zealand. Funders had no input in any part of the study.
