Identification of a W Variant Outbreak of Mycobacterium tuberculosis via Population-Based Molecular Epidemiology (original) (raw)

ESPITE THE INTRODUCTION OF the first antituberculin drugs almost 50 years ago, morbidity and mortality associated with Mycobacterium tuberculosis remains a major public health threat. Recently, the study of tuberculosis (TB) epidemiology and transmission, traditionally accomplished by patient contact tracing, has been augmented by the use of molecular strain typing. A striking example was the identification of the W strain, a multidrug-resistant (MDR) clone that caused disease in more than 350 patients in New York City and accounted for more than 25% of all MDR cases in the United States in the early 1990s. 1-4 This MDR and successful clone, associated with high mortality rates in both New York prisons and hospitals, has since become the "index" strain in the Public Health Research Institute (PHRI) TB Center (New York, NY) and has been the focus of a number of molecular epidemiological studies. 1-6 It is generally accepted that M tuberculosis isolates with identical inser-Author Affiliations are listed at the end of this article.