Leônidas e Maria Deane Institute (ILMD), Fiocruz Amazônia, Manaus, Amazonas, Brazil; Laboratory of infectious diseases and immunology, ILMD/Fiocruz Amazônia and PPGIBA/ICB-UFAM, Manaus, Brazil.
Laboratory of Emerging Viruses, Department of Genetics, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil.
Int J Infect Dis. 2023 Apr;129:142-151. doi: 10.1016/j.ijid.2023.01.033. Epub 2023 Feb 1.
Several Flaviviruses can co-circulate. Pre-existing immunity to one virus can modulate the response to a heterologous virus; however, the serological cross-reaction between these emerging viruses in dengue virus (DENV)-endemic regions are poorly understood.
A cross-sectional study was performed among the residents of Manaus city in the state of Amazonas, Brazil. The serological response was assessed by hemagglutination inhibition assay (HIA), enzyme-linked immunosorbent assay, and neutralization assay.
A total of 74.52% of the participants were immunoglobulin G-positive (310/416), as estimated by lateral flow tests. Overall, 93.7% of the participants were seropositive (419/447) for at least one DENV serotype, and the DENV seropositivity ranged between 84.8% and 91.0%, as determined by HIA. About 93% had antiyellow fever virus 17D-reactive antibodies, whereas 80.5% reacted to wild-type yellow fever virus. Zika virus (ZIKV) had the lowest seropositivity percentage (52.6%) compared with other Flaviviruses. Individuals who were DENV-positive with high antibody titers by HIA or envelope protein domain III enzyme-linked immunosorbent assay reacted strongly with ZIKV, whereas individuals with low anti-DENV antibody titers reacted poorly toward ZIKV. Live virus neutralization assay with ZIKV confirmed that dengue serogroup and ZIKV-spondweni serogroup are far apart; hence, individuals who are DENV-positive do not cross-neutralize ZIKV efficiently.
Taken together, we observed a high prevalence of DENV in the Manaus-Amazon region and a varying degree of cross-reactivity against emerging and endemic Flaviviruses. Epidemiological and exposure conditions in Manaus make its population susceptible to emerging and endemic arboviruses.
几种黄病毒可共同循环传播。对一种病毒的预先存在的免疫力可以调节对异源病毒的反应；然而，在登革热病毒（DENV）流行地区，这些新兴病毒之间的血清学交叉反应仍知之甚少。
在巴西亚马逊州玛瑙斯市的居民中进行了一项横断面研究。通过血凝抑制试验（HIA）、酶联免疫吸附试验和中和试验评估血清反应。
根据侧向流动试验估计，共有 74.52%的参与者免疫球蛋白 G 呈阳性（310/416）。总体而言，93.7%的参与者（419/447）至少对一种 DENV 血清型呈血清阳性，DENV 血清阳性率在 HIA 测定的 84.8%至 91.0%之间。约 93%的人对黄热病 17D 病毒有反应性抗体，而 80.5%的人对野生型黄热病病毒有反应。与其他黄病毒相比，寨卡病毒（ZIKV）的血清阳性率最低（52.6%）。在 HIA 或包膜蛋白结构域 III 酶联免疫吸附试验中具有高抗体滴度的 DENV 阳性个体对 ZIKV 反应强烈，而具有低抗 DENV 抗体滴度的个体对 ZIKV 反应不佳。用 ZIKV 进行的活病毒中和试验证实，登革热血清群和寨卡病毒-spondweni 血清群相距甚远；因此，DENV 阳性个体不能有效地交叉中和 ZIKV。
综上所述，我们观察到玛瑙斯-亚马逊地区 DENV 的高流行率以及对新兴和地方性黄病毒的不同程度的交叉反应。玛瑙斯的流行病学和暴露条件使其人群易感染新兴和地方性虫媒病毒。
