1. Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
2. Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
3. Maternal and Child Health Department, Ministry of Public Health Montevideo, Uruguay
4. Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Rome, Italy