|
|
 | |||||||||||||||||||||||||||||||||
 | |||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||
Background The immunogenicity of oral poliovirus vaccine (OPV), particularly the type 3 component, is lower in infants in most developing countries than in infants in industrialized countries. We conducted a multicenter trial in Oman to evaluate the response to a supplemental dose of four poliovirus vaccine formulations.
Methods At nine months of age, infants were randomly assigned to receive inactivated-poliovirus vaccine (IPV), administered subcutaneously; trivalent OPV manufactured in the United States or in Europe; or monovalent type 3 OPV. Serum samples were collected at enrollment and 7 and 30 days later. All of the infants had previously received five doses of OPV.
Results We enrolled 1025 infants; 785 (76.6 percent) met all the study requirements. At enrollment, 96.8 percent of the infants were seropositive for poliovirus type 1, 98.0 percent for type 2, and 88.0 percent for type 3. At 30 days there were no significant increases in type 3 seroprevalence or in the median antibody titer in the groups of infants who received OPV. Among the recipients of IPV, type 3 seroprevalence increased from 87.8 percent at enrollment to 97.1 percent at 30 days (P<0.001), and the median antibody titer increased from 1:228 to 1:1448 or higher (P<0.001). The rapid initial increase in the antibody titer suggests a secondary immune response.
Conclusions A supplemental dose of IPV has excellent immunogenicity and leads to increases in the titer of antibodies against type 3 poliovirus, whereas supplemental doses of the oral vaccines do not have these effects.
Source Information
From the Centers for Disease Control and Prevention, Atlanta (R.W.S., M.A.P.); the Ministry of Health, Muscat, Oman (A.J.M.S., P.M., F.M.); Royal Hospital, Muscat, Oman (S.A.-K.); Ruchill Hospital, Glasgow, United Kingdom (G.B.C.); and the Department of Vaccines and Biologicals, World Health Organization, Geneva (S.E.R.).
Address reprint requests to Information Services, National Immunization Program (E34), Centers for Disease Control and Prevention, 1600 Clifton Rd., Atlanta, GA 30333, or to rws4{at}cdc.gov.
This article has been cited by other articles:
HOME | SUBSCRIBE | SEARCH | CURRENT ISSUE | PAST ISSUES | COLLECTIONS | PRIVACY | HELP | beta.nejm.org Comments and questions? Please contact us. The New England Journal of Medicine is owned, published, and copyrighted © 2008 Massachusetts Medical Society. All rights reserved. |
Previous
