Garcia-Longoria Luz, Hellgren Olof, Bensch Staffan, de Lope Florentino, Marzal Alfonso
Departamento de Biología Animal,Universidad de Extremadura,E-06071 Badajoz,Spain.
Department of Biology,Molecular Ecology and Evolution Lab,Ecology Building,Lund University,SE- 22362 Lund,Sweden.
Parasitology. 2015 Aug;142(9):1215-20. doi: 10.1017/S0031182015000487. Epub 2015 May 13.
The identification of the regions where vector-borne diseases are transmitted is essential to study transmission patterns and to recognize future changes in environmental conditions that may potentially influence the transmission areas. SGS1, one of the lineages of Plasmodium relictum, is known to have active transmission in tropical Africa and temperate regions of Europe. Nuclear sequence data from isolates infected with SGS1 (based on merozoite surface protein 1 (MSP1) allelic diversity) have provided new insights on the distribution and transmission areas of these allelic variants. For example, MSP1 alleles transmitted in Africa differ from those transmitted in Europe, suggesting the existence of two populations of SGS1 lineages. However, no study has analysed the distribution of African and European transmitted alleles in Afro-Palearctic migratory birds. With this aim, we used a highly variable molecular marker to investigate whether juvenile house martins become infected in Europe before their first migration to Africa. We explored the MSP1 allelic diversity of P. relictum in adult and juvenile house martins. We found that juveniles were infected with SGS1 during their first weeks of life, confirming active transmission of SGS1 to house martins in Europe. Moreover, we found that all the juveniles and most of adults were infected with one European transmitted MSP1 allele, whereas two adult birds were infected with two African transmitted MSP1 alleles. These findings suggest that house martins are exposed to different strains of P. relictum in their winter and breeding quarters.
确定病媒传播疾病的传播区域对于研究传播模式以及识别未来可能影响传播区域的环境条件变化至关重要。残疟原虫的谱系之一SGS1在热带非洲和欧洲温带地区具有活跃传播。来自感染SGS1的分离株的核序列数据（基于裂殖子表面蛋白1（MSP1）等位基因多样性）为这些等位基因变体的分布和传播区域提供了新的见解。例如，在非洲传播的MSP1等位基因与在欧洲传播的不同，这表明存在两个SGS1谱系群体。然而，尚无研究分析非洲和欧洲传播的等位基因在非洲-古北界候鸟中的分布情况。为此，我们使用了一个高度可变的分子标记来研究家燕幼鸟在首次迁徙到非洲之前是否在欧洲就已感染。我们探究了成年和幼年家燕中残疟原虫的MSP1等位基因多样性。我们发现幼鸟在出生后的头几周就感染了SGS1，证实了SGS1在欧洲家燕中的活跃传播。此外，我们发现所有幼鸟和大多数成年鸟都感染了一种欧洲传播的MSP1等位基因，而两只成年鸟感染了两种非洲传播的MSP1等位基因。这些发现表明，家燕在其越冬地和繁殖地接触到了不同菌株的残疟原虫。
