Successful immunization of infants with and without maternal antibody by aerosolized measles vaccine. II. Vaccine comparisons and evidence for multiple antibody response
Sabin, A.B.; Flores Arechiga, A.; Fernández de Castro, J.; Albrecht, P.; Sever, J.L.; Shekarchi, I.
JAMA 251(18): 2363-2371
1984
ISSN/ISBN: 0098-7484 PMID: 6368888 Document Number: 240037
In 4 and 5 mo. old infants in whom the undiluted chick embryo fibroblast (CEF) Schwarz strain measles vaccine had a poor immunogenic effect, there was an increase in immunogenicity when the high sugar concentration was diminished without reference to added albumin. The human diploid cell (HDC) measles vaccine was still superior in this age group even in a lower concentration of the Ikic, Edmonston-Zagreb strain of virus. More aerosolized, HDC Ikic strain virus was required for high seroconversion rates in 4 and 5 mo. old infants who had higher titers of prevaccination plaque-neutralizing (PN) antibodies. Some of these infants had a delayed immune response that was absent at 6 wk but present at 3 mo. after vaccination. The data provided evidence that the PN and enzyme-linked immunosorbent assay [ELISA] techniques measured different antibodies that develop and persist in different ways in 4-5 mo. old infants. The HDC lyophilized measles vaccine yielded unexpectedly high seroconversion rates after s.c. injection of 5000 plaque-forming units (PFU) in 4, 5 and 6 mo. old infants: 69, 89 and 100%, respectively, at 14 wk. In 12-23 mo. old infants there was seroconversion of 92 and 100% at 6 wk after inhalation of an estimated 175 PFU of the CEF vaccine and 375 PFU of the HDC vaccine, respectively. Within 6 wk after vaccination, the PN antibody titers were significantly higher with the CEF vaccine (geometric mean titer of 2275) than with the HDC vaccine (geometric mean titer of 343).