Who Do You Know? A Simulation Study of Infectious Disease Control Through Contact Tracing

Contact tracing (also known as partner notification) is a primary means of controlling infectious diseases such as tuberculosis (TB), human immunodeficiency virus (HIV), and sexually transmitted diseases (STDs). The effectiveness of contact tracing depends on a number of factors including the contact tracing policy used, the social mixing network, and characteristics of the disease (e.g., the transmission mechanism, variability in infectiousness over time and across individuals, and the rate at which symptoms develop). We develop a simulation model for contact tracing and use it to explore the effectiveness of different contact tracing policies in a budget constrained setting. We evaluate several alternative contact tracing policies. We then introduce a cost-effectiveness framework and show how it can be used to determine the optimal level of investment in contact tracing. We first assume that the only incremental disease control is contact tracing. We then extend the analysis to consider the optimal allocation of a budget between contact tracing and screening for exogenous infections.