title: Factors affecting the seroconversion rate of 12-month-old babies after the first injection of measles vaccine in the southeast of Iran.
abstract: Within the past few years, several measles outbreaks have occurred in the southeast of Iran. To learn about the effectiveness of the immunization services for producing a serologic response against measles, this follow-up study was designed and implemented in the southeast of Iran. In Iran, all routine immunization services provided by the public sector are free of charge. The follow-up study was designed and implemented in 5 Urban Health Centers located in 3 districts of Sistan-va-BaluchestanProvince, Iran. In the pre-vaccination phase, 270 12-month-old babies were blood sampled; and in the post-vaccination phase, 4 to 7 weeks after Measles, Mumps, Rubella (MMR) vaccination, 236 of them were blood sampled (34 dropouts), and their sera were tested for IgG anti-measles antibodies, using indirect ELISA, in the National Reference Measles Laboratory. Out of the 236 participants, who had been blood sampled in the post-vaccination phase, 10 (3.7%) were excluded from the calculations of seroconversion rate, because they had protective levels of antibody before the vaccination. The seroconversion rate for the remaining 226 participants was 91.2% (95% confidence interval: 86.7 to 94.5). Among the variables studied, stunting (height-for-age z-score < -2) showed a strong relationship with the remaining seronegative after the vaccination (odds ratio = 5.6; 95% confidence interval: 1.7-18.2). The chance of seroconversion was inversely related to the mothers' levels of education (up to 9 y of education vs. above nine years) (odds ratio = 0.2; 95% confidence interval: 0.06-0.4). In the study population, the seroconversion rates for anti-measles antibodies after MMR vaccination are acceptable, even though in order to achieve the elimination goal, higher standards need to be achieved.
authors.affiliation: a Centre for Communicable Diseases Control , Ministry of Health and Medical Education , Tehran , Iran.
authors.forename: Seyed Mohsen
authors.initials: SM
authors.lastname: Zahraei
authors.affiliation: b Associate Professor of Epidemiology, Health Promotion Research Centre , School of Public Health, Zahedan University of Medical Sciences , Zahedan , Iran.
authors.forename: Shahrokh
authors.initials: S
authors.lastname: Izadi
authors.affiliation: c Professor of Virology, National Reference Laboratory for Measles and Rubella , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran.
authors.forename: Talat
authors.initials: T
authors.lastname: Mokhtari-Azad
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D003151:Community Health Centers; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007492:Iran; D008297:Male; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage* / Q000276:immunology*; D000069078:Seroconversion; D014505:Urban Population
chemical_list: D000914:Antibodies, Viral; D022542:Measles-Mumps-Rubella Vaccine
keywords: Iran; immunization; measles; seroconversion; stunting; vaccine