Lau Colleen, Aubry Maite, Musso Didier, Teissier Anita, Paulous Sylvie, Desprès Philippe, de-Lamballerie Xavier, Pastorino Boris, Cao-Lormeau Van-Mai, Weinstein Philip
Research School of Population Health, Australian National University, 62 Mills Rd, Canberra, Australian Capital Territory, ACT 0200, Australia.
Institut Louis Malardé, Papeete, Tahiti, French Polynesia.
Int J Infect Dis. 2017 Apr;57:73-76. doi: 10.1016/j.ijid.2017.01.041. Epub 2017 Feb 8.
An epidemic of Ross River virus (RRV) occurred in the South Pacific in 1979-1980, but RRV has not been thought to occur endemically outside Australia and Papua New Guinea. A seroprevalence study was conducted to determine whether RRV has circulated in American Samoa since 1980.
RRV ELISA IgG was performed on 200 serum samples collected in American Samoa in 2010; seroneutralization tests were performed on 60 representative samples.
Of 196 available ELISA IgG results, 145 (74%, 95% confidence interval 67-80%) were seropositive. Of the 60 samples subjected to seroneutralization testing, none of the 15 ELISA IgG-negative and 16 of the 45 ELISA IgG-positive samples neutralized RRV. ELISA IgG seroprevalence was higher in persons born before/during the 1979-1980 RRV outbreak (78.3%), but was also high (63.0%) in people born after the outbreak who had lived their entire lives in American Samoa.
This study provides serological evidence that RRV circulation is likely to have occurred in American Samoa after 1980. Considering there are no marsupials in American Samoa, this finding implies that other species are capable of acting as reservoir hosts and indicates the potential for RRV to circulate in a much wider area than those currently recognized.
1979 - 1980年南太平洋发生了罗斯河病毒（RRV）疫情，但此前认为RRV仅在澳大利亚和巴布亚新几内亚以外地区呈地方性流行。开展了一项血清阳性率研究，以确定自1980年以来RRV是否在美国萨摩亚群岛传播。
对2010年在美国萨摩亚群岛采集的200份血清样本进行RRV ELISA IgG检测；对60份代表性样本进行血清中和试验。
在196份可用的ELISA IgG检测结果中，145份（74%，95%置信区间67 - 80%）呈血清阳性。在接受血清中和试验的60份样本中，15份ELISA IgG阴性样本均未中和RRV，45份ELISA IgG阳性样本中有16份中和了RRV。在1979 - 1980年RRV疫情爆发前/期间出生的人群中，ELISA IgG血清阳性率较高（78.3%），但在疫情爆发后出生且一生都生活在美国萨摩亚群岛的人群中也较高（63.0%）。
本研究提供了血清学证据，表明1980年后RRV可能在美国萨摩亚群岛传播。鉴于美国萨摩亚群岛没有有袋动物，这一发现意味着其他物种可能充当储存宿主，并表明RRV有在比目前公认范围更广的地区传播的可能性。
