RESUMO
BACKGROUND: Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory illness in humans. Fundamental questions about circulating viruses and transmission routes remain. METHODS: We assessed routinely collected epidemiologic data for MERS-CoV cases reported in Saudi Arabia during 1 January-30 June 2015 and conducted a more detailed investigation of cases reported during February 2015. Available respiratory specimens were obtained for sequencing. RESULTS: During the study period, 216 MERS-CoV cases were reported. Full genome (n = 17) or spike gene sequences (n = 82) were obtained from 99 individuals. Most sequences (72 of 99 [73%]) formed a discrete, novel recombinant subclade (NRC-2015), which was detected in 6 regions and became predominant by June 2015. No clinical differences were noted between clades. Among 87 cases reported during February 2015, 13 had no recognized risks for secondary acquisition; 12 of these 13 also denied camel contact. Most viruses (8 of 9) from these 13 individuals belonged to NRC-2015. DISCUSSIONS: Our findings document the spread and eventual predominance of NRC-2015 in humans in Saudi Arabia during the first half of 2015. Our identification of cases without recognized risk factors but with similar virus sequences indicates the need for better understanding of risk factors for MERS-CoV transmission.
Assuntos
Infecções por Coronavirus/epidemiologia , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/classificação , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Epidemiologia Molecular , Filogenia , Arábia Saudita/epidemiologia , Análise de Sequência de DNA , Homologia de Sequência , Glicoproteína da Espícula de Coronavírus/genética , Adulto JovemAssuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Exposição Ambiental , Coronavírus da Síndrome Respiratória do Oriente Médio , Estações do Ano , Animais , Camelus/virologia , Infecções por Coronavirus/história , Infecções por Coronavirus/virologia , Genoma Viral , História do Século XXI , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/classificação , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Filogenia , Vigilância da População , Arábia Saudita/epidemiologia , Sequenciamento Completo do GenomaRESUMO
During July-August 2015, the number of cases of Middle East respiratory syndrome (MERS) reported from Saudi Arabia increased dramatically. We reviewed the 143 confirmed cases from this period and classified each based upon likely transmission source. We found that the surge in cases resulted predominantly (90%) from secondary transmission largely attributable to an outbreak at a single healthcare facility in Riyadh. Genome sequencing of MERS coronavirus from 6 cases demonstrated continued circulation of the recently described recombinant virus. A single unique frameshift deletion in open reading frame 5 was detected in the viral sequence from 1 case.