A51 Rubella genotype 1H is still circulating in Turkey

Rubella virus, the sole member of the Rubivirus genus in the Togaviridae family, is a positive-strand RNA virus. Based on phylogenetic analysis of sequences of the structural coding protein, two virus clades including a total of thirteen genotypes have been identified. Infection with rubella virus generally leads to mild disease with symptoms that include rash and low fever. In pregnancy, however, rubella infection can cause miscarriages and serial birth defects including hearing, vision, mental and heart impairment, which are collectively known as congenital rubella syndrome (CRS). CRS occurs in up to 85 per cent of children born to women with rubella infection during the first trimester of pregnancy. In addition, CRS can lead to neonatal deaths in up to 30 per cent of cases. Laboratory investigation plays an important role in both diagnosis and surveillance of rubella and CRS, since clinical diagnosis is unreliable and up to 50 per cent of infections are estimated to be subclinical. Because phylogenetic analysis of rubella virus genotypes can help determine whether circulating strains result from endemic transmissions or importations, laboratory surveillance for rubella also includes the molecular characterisation of viruses. Rubella genotype 1 H was detected in a seven-year-old patient’s urine specimen in 2016 (GenBank accession number KY048160). There are only three previous genotype 1 H sequences from Turkey which were collected in 2001. No sequences are available from countries bordering Turkey (except for one 2B from Iran). Other 1 H sequences are mostly from Russia and Belarus and none have been detected since 2008. The sequences of the recent isolate and three previous isolates cluster as a separate branch of genotype 1 H. It seems likely that this lineage of 1 H has been circulating in the country (and perhaps bordering countries) during the last fifteen years.