Bruce M C, Galinski M R, Barnwell J W, Donnelly C A, Walmsley M, Alpers M P, Walliker D, Day K P
Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford.
Parasitology. 2000 Sep;121 ( Pt 3):257-72. doi: 10.1017/s0031182099006356.
We describe the dynamics of co-infections of Plasmodium falciparum and P. vivax in 28 asymptomatic children by genotyping these species using the polymorphic loci Msp2 and Msp3alpha, respectively. The total number of Plasmodium spp. infections detected using 3 day sampling over 61 days varied between 1 and 14 (mean 6.6). The dynamics of P. falciparum and P. vivax genotypes varied greatly both within and amongst children. Periodicity in the detection of P. falciparum infections is consistent with the synchronous replication of individual genotypes. Replication synchrony of multiple co-infecting genotypes was not detected. In 4-year-old children P. falciparum genotype complexity was reduced and episodes lasted significantly longer (median duration > 60 days) when compared to children aged 5-14 years (median duration 9 days). P. vivax genotype complexity was not correlated with age but the episode duration was also longer for this species in 4-year-olds than in older children but was not as long as P. falciparum episodes. Recurrence of P. falciparum and P. vivax genotypes over weeks was observed. We interpret these major fluctuations in the density of genotypes over time as the result of the mechanism of antigenic variation thought to be present in these Plasmodium species.
我们通过分别使用多态性位点Msp2和Msp3α对这些疟原虫进行基因分型，描述了28名无症状儿童中恶性疟原虫和间日疟原虫合并感染的动态情况。在61天内采用3天采样检测到的疟原虫属感染总数在1至14之间变化（平均为6.6）。儿童体内以及儿童之间，恶性疟原虫和间日疟原虫基因型的动态变化差异很大。恶性疟原虫感染检测中的周期性与单个基因型的同步复制一致。未检测到多种合并感染基因型的复制同步性。与5至14岁儿童（中位持续时间9天）相比，4岁儿童的恶性疟原虫基因型复杂性降低，发作持续时间显著更长（中位持续时间>60天）。间日疟原虫基因型复杂性与年龄无关，但4岁儿童中该物种的发作持续时间也比大龄儿童更长，但不如恶性疟原虫发作持续时间长。观察到恶性疟原虫和间日疟原虫基因型在数周内反复出现。我们将这些基因型密度随时间的主要波动解释为这些疟原虫物种中存在的抗原变异机制的结果。
