A hypothesis test for the end of a common source outbreak

The objective of this article is to develop a hypothesis-testing procedure to determine whether a common source outbreak has ended. We consider the case when neither tire calendar date of exposure to the pathogen nor the exact incubation period distribution is known. The hypothesis-testing procedure is based on the spacings between ordered calendar dates of disease onset of tire cases. A simulation study was performed to evaluate the robustness of the methods to various models for tire incubation period of infectious diseases. We investigated the impact of multiple testing oil the overall outbreak-wise type I error probability. We derive expressions for tire outbreak-wise type I error probability and show that multiple testing has minimal effect oil inflating that error probability. The results are discussed in the context of the 2001 U.S. anthrax outbreak.