Nunes Marcio Roberto Teixeira, Faria Nuno Rodrigues, de Vasconcelos Janaina Mota, Golding Nick, Kraemer Moritz U G, de Oliveira Layanna Freitas, Azevedo Raimunda do Socorro da Silva, da Silva Daisy Elaine Andrade, da Silva Eliana Vieira Pinto, da Silva Sandro Patroca, Carvalho Valéria Lima, Coelho Giovanini Evelim, Cruz Ana Cecília Ribeiro, Rodrigues Sueli Guerreiro, Vianez Joao Lídio da Silva Gonçalves, Nunes Bruno Tardelli Diniz, Cardoso Jedson Ferreira, Tesh Robert B, Hay Simon I, Pybus Oliver G, Vasconcelos Pedro Fernando da Costa
Center for Technological Innovation, Evandro Chagas Institute, Ministry of Health, Ananindeua, PA, 67030-000, Brazil.
Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
BMC Med. 2015 Apr 30;13:102. doi: 10.1186/s12916-015-0348-x.
In December 2013, an outbreak of Chikungunya virus (CHIKV) caused by the Asian genotype was notified in the Caribbean. The outbreak has since spread to 38 regions in the Americas. By September 2014, the first autochthonous CHIKV infections were confirmed in Oiapoque, North Brazil, and in Feira de Santana, Northeast Brazil.
We compiled epidemiological and clinical data on suspected CHIKV cases in Brazil and polymerase-chain-reaction-based diagnostic was conducted on 68 serum samples from patients with symptom onset between April and September 2014. Two imported and four autochthonous cases were selected for virus propagation, RNA isolation, full-length genome sequencing, and phylogenetic analysis. We then followed CDC/PAHO guidelines to estimate the risk of establishment of CHIKV in Brazilian municipalities.
We detected 41 CHIKV importations and 27 autochthonous cases in Brazil. Epidemiological and phylogenetic analyses indicated local transmission of the Asian CHIKV genotype in Oiapoque. Unexpectedly, we also discovered that the ECSA genotype is circulating in Feira de Santana. The presumed index case of the ECSA genotype was an individual who had recently returned from Angola and developed symptoms in Feira de Santana. We estimate that, if CHIKV becomes established in Brazil, transmission could occur in 94% of municipalities in the country and provide maps of the risk of importation of each strain of CHIKV in Brazil.
The etiological strains associated with the early-phase CHIKV outbreaks in Brazil belong to the Asian and ECSA genotypes. Continued surveillance and vector mitigation strategies are needed to reduce the future public health impact of CHIKV in the Americas.
2013年12月，加勒比地区通报了由亚洲基因型引起的基孔肯雅病毒（CHIKV）疫情。此后，该疫情已蔓延至美洲的38个地区。到2014年9月，在巴西北部的奥亚波克以及巴西东北部的费拉德桑塔纳首次确认了本土CHIKV感染病例。
我们汇总了巴西疑似CHIKV病例的流行病学和临床数据，并对2014年4月至9月出现症状的患者的68份血清样本进行了基于聚合酶链反应的诊断。选择了2例输入性病例和4例本土病例进行病毒繁殖、RNA分离、全长基因组测序及系统发育分析。然后我们遵循美国疾病控制与预防中心/泛美卫生组织的指南，估算CHIKV在巴西各市建立传播的风险。
我们在巴西检测到41例CHIKV输入病例和27例本土病例。流行病学和系统发育分析表明，亚洲CHIKV基因型在奥亚波克出现了本地传播。出乎意料的是，我们还发现东中非南部基因型（ECSA）在费拉德桑塔纳传播。ECSA基因型的假定指示病例是一名最近从安哥拉返回并在费拉德桑塔纳出现症状的个体。我们估计，如果CHIKV在巴西建立传播，该国94%的市可能会出现传播，并提供了巴西每种CHIKV毒株输入风险的地图。
与巴西早期CHIKV疫情相关的病原毒株属于亚洲和ECSA基因型。需要持续监测和媒介控制策略，以降低未来CHIKV对美洲公共卫生的影响。
