Evolution of infection in people as a function of asymmetry in population distribution (image) American Institute of Physics Share Print E-Mail Caption Evolution of infection in people as a function of asymmetry in population distribution shows that when the border from high density to low-density areas is closed, total overall disease spread doubles. Credit Image courtesy of Massimiliano Zanin Usage Restrictions Journalists may use this image only with appropriate credit. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.