To identify factors that influence individual and group transmission of Chlamydia, the authors conducted community-wide contact tracing of chlamydia cases in Colorado Springs, Colorado, from mid-1996 to mid-1997. Case patients identified persons with whom they had had contact during the 6 months preceding diagnosis; contacts were actively sought and offered DNA amplification testing. Sexual con...

Abstract: We discuss basically the importance of reproduction number in Mathematical modeling as a summary measure of the transmission potential of an infectious disease.The basic reproduction number R0 for a compartmental disease model is often calculated by the next generation matrix (NGM) approach. It provides significant insight into the transmission dynamics of a disease and can guide stra...

The possibility of relapse is introduced into a mathematical model for the transmission of Plasmodium vivax malaria. In the model, the human population is divided into four classes: susceptible, infected, dormant and recovered. Loss of immunity by individuals in the recovered class moves these individuals back into the susceptible class. Two equilibrium states are found, a disease-free state an...