Age-related efficacy of Shigella O-specific polysaccharide conjugates in 1-4-year-old Israeli children.

Background: Despite its high worldwide morbidity and mortality, there is yet no licensed vaccine for shigellosis. We reported the safety and immunogenicity of Shigella O-specific polysaccharide-protein conjugates in adults and young children and efficacy of Shigella sonnei conjugate in young adults.

Methods: A double-blinded, randomized and vaccine-controlled Phase 3 evaluation of S.

The effect of active immunization on varicella-related hospitalizations in Israel.

The purpose of this study is to report on the impact of introduction of the varicella vaccine "Varilix" on hospitalizations due to varicella, following licensure in Israel in June, 2000. Data on children hospitalized throughout Israel with the diagnosis of varicella were collected from 1998 until 2003. The national rate of varicella-related hospitalizations decreased during the period 2001-2002.

O-specific [corrected] polysaccharide conjugate vaccine-induced [corrected] antibodies prevent invasion of Shigella into Caco-2 cells and may be curative.

The O-specific polysaccharide (O-SP) domain of Shigella LPS is both an essential virulence factor and a protective antigen for this genus. A critical level of serum IgG anti-O-SP was shown to confer immunity to shigellosis, likely by complement-mediated bacteriolysis of the inoculum. Conjugate Shigella O-SP vaccines were shown to be safe and immunogenic in children, and, in a preliminary study, Shigella sonnei vaccine was protective in young adults.