Field trial of a vaccine against new world cutaneous leishmaniasis in an at-risk child population: how long does protection last?
During 12 months of follow-up in a randomized double-blind controlled field study, a killed whole-promastigote vaccine cocktail plus bacille Calmette-Guérin (BCG) adjuvant significantly reduced the incidence of cutaneous leishmaniasis (CL) in Ecuadorian children, compared with BCG alone. To determine how much longer protection might continue, the study was reblinded to permit 48 additional months of follow-up. During months 13-18, CL incidence remained lower in the vaccine group, compared with that in the control group (5.9% vs. 13.8%; chi2=8.8; P=.003), with vaccine efficacy calculated at 56.5% (95% confidence interval, 18.7%-76.7%); however, during months 24-60, no significant between-group differences were detected. Periodic administration of boosters may be necessary to maintain whole-parasite-vaccine protection against New World CL.
Armijos
Rodrigo X
RX
College of Health Sciences, Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA. rxarmijos@utep.edu
Weigel
M Margaret
MM
Romero
Luciano
L
Garcia
Vinicio
V
Salazar
Jorge
J
D000276:Adjuvants, Immunologic; D000818:Animals; D001500:BCG Vaccine; D002648:Child; D002675:Child, Preschool; D004484:Ecuador; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007891:Leishmania / Q000276:immunology; D007896:Leishmaniasis / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control*; D008297:Male; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012307:Risk Factors; D013997:Time Factors
D000276:Adjuvants, Immunologic; D001500:BCG Vaccine; D016052:Protozoan Vaccines