Vaccine
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Randomized Controlled Trial Clinical Trial
Immunogenicity of high-titre AIK-C or Edmonston-Zagreb vaccines in 3.5-month-old infants, and of medium- or high-titre Edmonston-Zagreb vaccine in 6-month-old infants, in Kinshasa, Zaire.
The effect of measles vaccine potency was evaluated among 485 children aged 6 months, and the effect of vaccine strain was evaluated among 538 children aged 3.5 months, in Kinshasa, Zaire. Children aged 6 months were randomly assigned to receive either high-titre Edmonston-Zagreb (EZ-H), potency 5.7 log10/dose, or medium-titre EZ (EZ-M), potency 4.7 log10/dose, those aged 3.5 months were randomly assigned to receive either AIK-C, potency 5.5 log10/dose, or EZ-H, and were revaccinated with EZ-M vaccine at age 9.5 months. Measles antibodies were measured using the plaque reduction neutralization assay. ⋯ After revaccination at age 9.5 months, 81% of children in the AIK-C group and 73% in the EZ-H group had antibody levels > 200 mIU (p = 0.056). A retrospective survey was conducted in January 1993 to determine the mortality experience of vaccine groups, and information was obtained for 94% of the children. A total of 44 deaths (4%) were identified, with no significant differences between groups when stratified by age at vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)
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Comparative Study
Immunogenicity of rabies vaccines used during an urban epizootic of rabies in Mexico.
From 1 July 1987 to 31 December 1988, 30% of 247 rabid dogs in Hermosillo, Mexico had a positive history of rabies vaccination. Serosurveys suggested that inactivated suckling mouse brain vaccine (INACT-SMBV) and inactivated tissue culture vaccine (INACT-TC) used before and during the epizootic were poor immunogens. ⋯ Rabies vaccines should be evaluated periodically by measuring antibody responses in animals. In some circumstances, minimum seroconversion rates and antibody titres in vaccinated animals may be better measures of immunogenicity than relative potency.