Towards measles elimination: Phylogenetic analysis of measles viruses in Turkey (2012-2013) and identification of genotype D8

Abstract

Molecular characterization of different measles virus (MV) strains is essential to combat the disease. Sixty measles MV strains were obtained from throat swabs or urine of patients in Turkey between 2012 and 2013 and characterized. MV RNA sequences (n = 60) were analysed for 456 nucleotides representing hypervariable domain of the nucleoprotein (N) gene. Of the 60 strains analysed 53 were the D8 genotype, 6 were B3, 1 was D4, and 1 was A. This report describes MV genotype D8 that was involved in a measles outbreak in Turkey. Sequences of most genotype D8 strains (n = 51) were identical to the sequence of variant D8-Frankfurt-Main, which has been associated with outbreaks throughout Europe. Despite the lack of epidemiologic information, a phylogenetic analysis suggested that the genotype D8 MV may have been brought to Turkey from elsewhere. Phylogenetic and epidemiological findings suggested that strains identified in tourists and associated with importation included one strain of genotype D8, one strain of genotype B3, and one strain of genotype D4. These findings from the 2012 to 2013 outbreak in Turkey confirm that pockets of unimmunised individuals are making the country susceptible to measles outbreaks. To prevent further outbreaks, deliberate and sustained effort must be made to reach, and immunise susceptible age groups. Towards measles elimination process, continued molecular surveillance of measles strains in Turkey will help identify transmission patterns of virus and evaluate vaccination efforts. J. Med. Virol. 88:1867-1873, 2016. © 2016 Wiley Periodicals, Inc.

Molecular characterization of measles viruses in China: Circulation dynamics of the endemic H1 genotype from 2011 to 2017

“…The elimination of measles is an important goal for public health worldwide. To ensure the success of measles elimination, a two-dose vaccine regimen with 95% coverage for all population groups and age cohorts is necessary to establish herd immunity and prevent subsequent epidemics [6, 39]. China is currently in the measles pre-elimination phase.…”

“…The measles virus is monotypic, but genetic variability exists among wild-type strains [2]. The World Health Organization (WHO) currently recognizes 8 clades (A-H) and 24 genotypes of measles virus based on sequence analyses of the carboxyl-terminal (C-terminal) region of the nucleoprotein (N) gene and the entire hemagglutinin (H) gene [3–6].…”

“…Genetic analysis of circulating wild-type viruses together with epidemiological information is a critical component of measles surveillance because it can help confirm the source of a virus or suggest a source for unknown-origin cases as well as establish links, trace the transmission pathway, and classify suspected cases as vaccine reactions [5]. Acquiring genotype information of circulating measles viruses is one of three essential criteria for verifying the progress, achievement and maintenance of measles elimination [5, 6]. In addition, imported measles virus strains can be identified in a timely manner through molecular characterization, thereby providing data to support the development of strategies to interrupt the spread of imported measles virus [4–6].…”

“…Acquiring genotype information of circulating measles viruses is one of three essential criteria for verifying the progress, achievement and maintenance of measles elimination [5, 6]. In addition, imported measles virus strains can be identified in a timely manner through molecular characterization, thereby providing data to support the development of strategies to interrupt the spread of imported measles virus [4–6].…”

Epidemiology and molecular characterization of the re-emerging measles virus among children and adults in the Haut-Ogooue, Gabon

“…Measles is one of the most infectious diseases with a high mortality rate worldwide. Therefore, the World Health Organization (WHO) recommended a molecular surveillance of measles strains and established a vaccination program for measles elimination [3, 4]. In 2010, the World Health Assembly planned to increase routine coverage with the first dose of measles vaccine for children aged one year old to ≥90% nationally and ≥ 80% in every district, reduce and maintain annual measles incidence at < 5 cases per million and reduce mortality by 95% from a 2000 estimate in order to reach eradication by 2015 [3].…”