使用血清学方法监测瓦努阿图疟疾传播的变化。
Using serological measures to monitor changes in malaria transmission in Vanuatu.
机构信息
London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
出版信息
Malar J. 2010 Jun 16;9:169. doi: 10.1186/1475-2875-9-169.
BACKGROUND
With renewed interest in malaria elimination, island environments present unique opportunities to achieve this goal. However, as transmission decreases, monitoring and evaluation programmes need increasingly sensitive tools to assess Plasmodium falciparum and Plasmodium vivax exposure. In 2009, to assess the role of serological markers in evaluating malaria transmission, a cross-sectional seroprevalence study was carried out in Tanna and Aneityum, two of the southernmost islands of the Vanuatu archipelago, areas where malaria transmission has been variably reduced over the past few decades.
METHODS
Malaria transmission was assessed using serological markers for exposure to P. falciparum and P. vivax. Filter blood spot papers were collected from 1,249 people from Tanna, and 517 people from Aneityum to assess the prevalence of antibodies to two P. falciparum antigens (MSP-119 and AMA-1) and two P. vivax antigens (MSP-119 and AMA-1). Age-specific prevalence was modelled using a simple catalytic conversion model based on maximum likelihood to generate a community seroconversion rate (SCR).
RESULTS
Overall seropositivity in Tanna was 9.4%, 12.4% and 16.6% to P. falciparum MSP-119, AMA-1 and Schizont Extract respectively and 12.6% and 15.0% to P. vivax MSP-119 and AMA-1 respectively. Serological results distinguished between areas of differential dominance of either P. vivax or P. falciparum and analysis of age-stratified results showed a step in seroprevalence occurring approximately 30 years ago on both islands, indicative of a change in transmission intensity at this time. Results from Aneityum suggest that several children may have been exposed to malaria since the 2002 P. vivax epidemic.
CONCLUSION
Seroepidemiology can provide key information on malaria transmission for control programmes, when parasite rates are low. As Vanuatu moves closer to malaria elimination, monitoring changes in transmission intensity and identification of residual malaria foci is paramount in order to concentrate intervention efforts.
背景
随着人们对消除疟疾的兴趣重新燃起，岛屿环境为实现这一目标提供了独特的机会。然而，随着传播的减少，监测和评估计划需要越来越敏感的工具来评估恶性疟原虫和间日疟原虫的暴露情况。2009 年，为了评估血清学标志物在评估疟疾传播中的作用，在瓦努阿图群岛最南端的塔纳和安尼托姆两个岛屿上进行了一项横断面血清流行率研究，这两个地区在过去几十年中疟疾传播情况有所不同。
方法
使用恶性疟原虫和间日疟原虫暴露的血清学标志物评估疟疾传播情况。从塔纳采集了 1249 人、从安尼托姆采集了 517 人滤纸血斑，以评估对两种恶性疟原虫抗原（MSP-119 和 AMA-1）和两种间日疟原虫抗原（MSP-119 和 AMA-1）的抗体的流行率。使用基于最大似然法的简单催化转换模型对年龄特异性流行率进行建模，以生成社区血清转化率（SCR）。
结果
塔纳的总血清阳性率分别为恶性疟原虫 MSP-119、AMA-1 和裂殖体提取物的 9.4%、12.4%和 16.6%，间日疟原虫 MSP-119 和 AMA-1 的血清阳性率分别为 12.6%和 15.0%。血清学结果区分了恶性疟原虫或间日疟原虫优势区域，年龄分层结果分析显示，这两个岛屿大约 30 年前出现了血清阳性率的一个转折点，表明此时传播强度发生了变化。安尼托姆的结果表明，自 2002 年间日疟原虫流行以来，可能有几个儿童感染了疟疾。
结论
当寄生虫率较低时，血清流行病学可以为控制规划提供疟疾传播的关键信息。随着瓦努阿图向消除疟疾迈进，监测传播强度的变化和识别残留的疟疾焦点至关重要，以便集中干预措施。
Zotero 插件