Genotypic and antigenic characterization of hemagglutinin proteins of African measles virus isolates

A comprehensive phylogenetic study based on the hemagglutinin (H) protein o f all known African measles virus (MV) isolates is presented. The study inc ludes 64 new H gene sequences from Ghana, Nigeria and South Africa as well as viruses from Zambia and The Gambia for which only incomplete sequencing data were available and that have previously not been genotyped. The result s provide further support to the tentative assignment of the Nigerian and G hanaian viruses to a new genotype B3 within clade B. A distinct geographic distribution pattern emerged with clade B viruses circulating exclusively i n African countries north of the equator. All MV strains from southern Afri ca grouped in clades A and D with the majority of viruses belonging to geno type D4. The viruses considerably differed by their sensitivity to neutrali zation by monoclonal antibodies (mAb), but three selected antibodies were s ufficient to distinguish between African MVs representing four different ge notypes. (C) 1999 Elsevier Science B.V. All rights reserved.