1. From the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia; National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Denver, Colorado; University of the Witwatersrand, Johannesburg, South Africa;
2. National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, Ohio; Dallas County Department of Health and Human Services and Texas Health Presbyterian Hospital Dallas, Dallas, Texas; and Texas Department of State Health Services, Austin, Texas.