The Vi Conjugate Typhoid Vaccine Is Safe, Elicits Protective Levels of IgG Anti-Vi, and Is Compatible with Routine Infant Vaccines

• DOI: 10.1128/cvi.00532-10
• Publication Date: 2011-03-17T00:54:33Z
• Authors: Vu Dinh Thiem; Feng-Ying C. Lin; Do Gia Canh; Nguyen Hong Son; Dang Duc Anh; Nguyen Duc Mao; Chiayung Chu; Steven W. Hunt; John B. Robbins; Rachel Schneerson; Shousun C. Szu
• Keywords: Conjugate; Typhoid vaccine

Typhoid fever remains a serious problem in developing countries. Current vaccines are licensed for individuals who 5 years old or older. A conjugate of the capsular polysaccharide (CP) Salmonella enterica serovar Typhi (Vi) bound to recombinant exoprotein Pseudomonas aeruginosa (Vi-rEPA) enhanced Vi immunogenicity and protected 2- 5-year-olds Vietnam. In this study, Vi-rEPA was evaluated use infants. total 301 full-term Vietnamese infants received Expanded Program on Immunization (EPI) alone with Haemophilus influenzae type b-tetanus toxoid (Hib-TT) at 2, 4, 6 months Hib-TT 12 months. Infants were visited 6, 24, 48 h after each injection monitor adverse reactions. Maternal, cord, infant sera assayed IgG anti-Vi antibodies Hib CP diphtheria, tetanus, pertussis toxins 7, 12, 13 No vaccine-related reactions occurred. group, geometric mean (GM) increased from cord level 0.66 17.4 enzyme-linked immunosorbent assay units (EU) 7 months, declined 4.76 EU 50.1 1 month 4th dose (95% had levels ≥ 3.5 EU, estimated protective level). Controls no increase GM. <3.5 responded significantly higher than those EU. Anti-diphtheria, -tetanus, -pertussis toxin similar all groups. safe, induced levels, compatible EPI vaccines, it can be used High partially suppressed responses Vi-rEPA.