Scientific Publications by FDA Staff

Vaccine 2005 May 9;23(25):3247-55

Follow-up of infants given measles vaccine at 6 months of age: antibody and CMI responses to MMRII at 15 months of age and antibody levels at 27 months of age.

Carson MM, Spady DW, Beeler JA, Krezolek MP, Audet S, Pabst HF

Carson MM, Capital Hlth, Publ Hlth Div, Suite 1800 Coll Plaza,8215-112 St, Edmonton, AB T6G 2C8, Canada Univ Alberta, Dept Pediat, Edmonton, AB T6G 2R7, Canada US FDA, Div Viral Prod, Bethesda, MD 20892 USA

The worldwide elimination of measles is an important target. In developed countries, to control measles outbreaks, immunization from 6 months of age is recommended. In this study, infants (n = 290) who were (1) born to mothers with natural immunity or to vaccinated mothers and (2) previously immunized with Connaught (CLL) or AIK-C measles vaccine at 6 months of age, were evaluated for measles immunity before and after measles-mumps-rubella (MMRII at 15 months of age. Eight weeks after MMRII, 98.9% of infants were seropositive by enzyme immunoassay (EIA) and 70% demonstrated measles specific cellular immunity by blast transformation (BT) of lymphocytes. At 27 months of age, 98.4% of infants had protective antibody levels by plaque reduction neutralization (PRN) test. These results suggest that AIK-C and CLL vaccines elicit durable protective immunity in young infants when used in early immunization programs.