Australian Defence Force Malaria and Infectious Disease Institute, Weary Dunlop Drive, Gallipoli Barracks, Enoggera, QLD 4051, Australia.
Queensland Institute of Medical Research-Berghofer Medical Research Institute, Heston, QLD 4029, Australia.
Viruses. 2023 Jan 30;15(2):394. doi: 10.3390/v15020394.
Barmah Forest virus (BFV), Chikungunya virus (CHIKV) and Ross River virus (RRV) belong to the genus of the family All three virus infections have been reported in Papua New Guinea (PNG) previously, but the exact prevalence and distribution of these three alphaviruses in PNG has not been established. Sera collected from 204 PNG Military Personnel (PNGMP) study participants in April 2019 was tested for the presence of anti-BFV, anti-CHIKV and anti-RRV immunoglobulin G (IgG) antibodies using commercially available enzyme-linked immunosorbent assay (ELISA) IgG detection kits, as well as for specific neutralizing antibodies (NAb) against individual viruses. Overall, sero-positivity of the sera was anti-BFV IgG 12.3% (25/204), anti-BFV NAb 8.3% (17/204); anti-CHIKV IgG 47.1% (96/204), anti-CHIKV NAb 34.8% (71/204); and anti-RRV IgG 93.1% (190/204), anti-RRV NAb 56.4% (115/204), respectively. Of the 137/204 participants that were Nab-positive for at least one virus, we identified 4 BFV, 40 CHIKV and 73 RRV single infections, and 9 RRV+CHIKV and 11 BFV+RRV double infections. The lower proportion of NAb sero-positive compared to the ELISA IgG sero-positive assay samples suggests that the currently available commercial ELISA detection kits for these three alphaviruses may not be suitable for diagnostic/surveillance purposes in endemic areas such as PNG, due to serological cross-reactivity among these three alphaviruses. Laboratory testing using known positive control sera indicated no cross-neutralization between BFV and RRV; however, some RRV or BFV single infection human sera demonstrated low-level cross-neutralization against CHIKV (the ratio of RRV/CHIKV NAb titers or BFV/CHIKV ≥ 4). Our preliminary results indicate that the majority of PNGMP have previously been exposed to RRV, with mild exposure to CHIKV and low-level exposure to BFV, suggesting that multiple alphaviruses have been circulating among PNGMP. The transmission landscapes of these three alphaviruses across PNG should be prioritized for further investigation, including identification of specific vectors and hosts that mediate human spillover in order to mitigate future outbreaks. Ongoing education regarding precautionary and protective measures are needed to better protect individuals who travel to PNG.
巴尔马森林病毒（BFV）、基孔肯雅热病毒（CHIKV）和罗斯河病毒（RRV）属于 甲病毒属。 这三种病毒感染此前均已在巴布亚新几内亚（PNG）报告过，但这三种甲病毒在 PNG 的确切流行率和分布情况尚未确定。 2019 年 4 月，从 204 名巴布亚新几内亚军人（PNGMP）研究参与者采集的血清，使用市售酶联免疫吸附试验（ELISA）IgG 检测试剂盒检测 BFV、CHIKV 和 RRV 免疫球蛋白 G（IgG）抗体的存在情况，以及针对个体病毒的特异性中和抗体（NAb）。 总体而言，血清的血清阳性率为 BFV IgG 为 12.3%（25/204），BFV NAb 为 8.3%（17/204）；CHIKV IgG 为 47.1%（96/204），CHIKV NAb 为 34.8%（71/204）；RRV IgG 为 93.1%（190/204），RRV NAb 为 56.4%（115/204）。 在至少有一种病毒的 Nab 阳性的 137/204 名参与者中，我们鉴定出 4 例 BFV、40 例 CHIKV 和 73 例 RRV 单感染，以及 9 例 RRV+CHIKV 和 11 例 BFV+RRV 双重感染。 与 ELISA IgG 血清阳性检测样本相比，NAb 血清阳性样本的比例较低，这表明目前市售的这三种甲病毒的商业 ELISA 检测试剂盒可能不适合 PNG 等流行地区的诊断/监测目的，因为这三种甲病毒之间存在血清学交叉反应。 使用已知阳性对照血清进行的实验室检测表明 BFV 和 RRV 之间没有交叉中和；然而，一些 RRV 或 BFV 单感染人类血清对 CHIKV 表现出低水平的交叉中和（RRV/CHIKV NAb 滴度比或 BFV/CHIKV≥4）。 我们的初步结果表明，大多数 PNGMP 此前曾接触过 RRV，轻度接触 CHIKV，低度接触 BFV，表明多种甲病毒一直在 PNGMP 中传播。 应优先对这些三种甲病毒在 PNG 的传播情况进行进一步调查，包括鉴定介导人类溢出的特定媒介和宿主，以减轻未来的暴发。 有必要对前往 PNG 的个人进行关于预防和保护措施的持续教育，以更好地保护他们。
