Comparison of AIK-C measles vaccine in infants at 6 months with schwarz vaccine at 9 months: A randomized controlled trial in Ghana

Abstract

In a randomized controlled trial in a measles endemic area, standard-dose (4.0 log10pfu) AIK-C measles vaccine administered at 6 months of age was compared to standard-dose Schwarz vaccine (3.7log10pfu) given at 9 months. Seroconversion rates at 3 and 6 months after immunization in the two groups were comparable and similar. The geometric mean titres achieved were, however, significantly higher in the Schwarz group (P < 0.05). No immediate serious side-effects were observed with either vaccine. We conclude that standard-dose AIK-C measles vaccine can be recommended for measles immunization in children below 9 months of age, especially in highly endemic and high-risk areas in developing countries. PIP:

The seroresponse of standard-dose heat-stable AIK-C measles vaccine administered to infants at 6 months of age was compared to that of standard-dose Schwarz vaccine administered at 9 months of age in a measles-endemic area in West Africa. The study was conducted in Asamankese, the capital town of Ghana's East Akim District. Infants 24-27 weeks of age who had been attending the Asamankese maternal-child health clinic regularly and had received all the required immunizations were enrolled and randomly assigned to receive the AIK-C (n = 184) or the Schwarz (n = 193) vaccine. No severe adverse reactions were reported during the 10-day follow-up period in either vaccine group. In the AIK-C group, 96.9% of infants who were seronegative at preimmunization and 79.4% of those with preexisting antibodies had seroconverted by 3 months after immunization; at 6 months after immunization, these rates were 97.3% and 100%, respectively. In the Schwarz group, 98.2% of infants seronegative at immunization and 100% of those with preexisting antibodies seroconverted by 3 months after immunization; at 6 months, these rates were 99.1% and 80%, respectively. Although the geometric mean titres achieved were significantly higher in the Schwarz vaccine group, these titres were above the protective level of 200 mIU in the AIK-C group. Administration of measles vaccine at a younger age may be more easily incorporated into current Expanded Program on Immunization schedules.