title: Comparison of neutralizing antibody titers against outbreak-associated measles genotypes (D4, H1 and B3) in Iran.
abstract: Despite the accessibility of a promising vaccine, outbreaks of the measles virus (MV) take place even in well-vaccinated populations. D4, H1 and B3 genotypes have been detected regularly in different regions of Iran. These observations highlight the necessity of evaluating the protective efficacy of the vaccine against currently circulating MV genotypes during the elimination phase. A focus reduction neutralization test has been developed to measure the neutralizing antibodies against different genotypes of MV, such as H1, D4, B3 and vaccine strain (A), in children after second doses of measles vaccine. The geometric mean titer (GMT) rates of the sera against D4, H1, B3 and A genotypes were 95.9, 90.5, 32.0 and 76.1, respectively. Low GMTs of antibody against the B3 genotype compared with the other genotypes were indicated. Based on the current study results, the MV antibody titers in the sera of vaccinated cases are sufficient to neutralize all circulating genotypes in Iran; however, neutralizing antibody titers were lower for the B3 genotype than for the H1, D4 and A genotypes. The heterogeneous nature of MV, for instance the nucleotide sequence diversity between different strains, necessitates the evaluation of the protective efficacy of the vaccine against measles B3 genotype in countries where this virus has been the most commonly identified circulating genotype.
authors: Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran.
authors: Ghazal Sadat
authors: GS
authors: Fatemi Nasab
authors: Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran.
authors: Vahid
authors: V
authors: Salimi
authors: Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran.
authors: Simin
authors: S
authors: Abbasi
authors: Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran.
authors: Fatemeh
authors: F
authors: Adjami Nezhad Fard
authors: Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran mokhtari@tums.ac.ir.
authors: Talat
authors: T
authors: Mokhtari Azad
mesh_terms: D057134:Antibodies, Neutralizing / Q000097:blood* / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D000918:Antibody Specificity / Q000235:genetics / Q000276:immunology; D002675:Child, Preschool; D004196:Disease Outbreaks; D005260:Female; D005838:Genotype; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007075:Immunoglobulin M / Q000097:blood / Q000276:immunology; D007492:Iran / Q000453:epidemiology; D008297:Male; D008457:Measles / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology*; D008459:Measles virus / Q000235:genetics* / Q000276:immunology*; D009500:Neutralization Tests; D014611:Vaccination
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M
keywords: Iran; focus reduction neutralization; genotypes; measles virus; vaccine efficacy