[1] Univ Colorado, Div Infect Dis, Anschutz Med Campus, Aurora, CO 80045 USA
[2] Univ Colorado, Anschutz Med Ctr, Dept Neurol, Neuroinfect Dis Grp, Aurora, CO 80045 USA
[3] Univ Colorado, Anschutz Med Ctr, Div Infect Dis, Aurora, CO 80045 USA
[4] Hosp Infantil Mexico Dr Federico Gomez, Federico Gomez, Mexico City, DF, Mexico
[5] Univ Colorado, Anschutz Med Ctr, Dept Immunol & Microbiol, Aurora, CO USA
[6] Colorado Sch Publ Hlth, Dept Epidemiol, Aurora, CO USA