The risk of malarial infections and disease in Papua New Guinean children
The risk of malarial infections and disease in Papua New Guinean children
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DOI：
10.4269/ajtmh.2007.76.997
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发表时间：
2007-06-01
影响因子：
3.3
通讯作者：
Mueller, Ivo
中科院分区：
文献类型：
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作者：
Michon, Pascal;Cole-Tobian, Jennifer L.;Mueller, Ivo
在一项针对 206 名巴布亚新几内亚学童的再感染治疗研究中，我们检查了不同疟原虫种类引起的再感染和症状性疟疾的风险。尽管在六个月的积极随访中，儿童获得聚合酶链反应可检测的恶性疟原虫和间日疟原虫感染的数量相似（恶性疟原虫= 5.00，间日疟原虫= 5.28），但他们患有症状的恶性疟原虫疟疾（1.17/年）的可能性是间日疟原虫疟疾（0.06/年）的21倍。 9岁以上儿童感染低至中度（> 150/μL）密度间日疟原虫的风险降低（调整后危险率[AHR] = 0.65和0.42），而随着年龄的增长，恶性疟原虫感染风险也有类似的降低，仅在寄生虫血症> 5,000/μL（AHR = 0.49）和有症状发作（AHR = 0.51）。三日疟原虫和卵形疟原虫的感染和症状发作很少见。因此，到九岁时，儿童就获得了对间日疟原虫几乎完全的临床免疫力，其特点是对寄生虫密度的严格控制，而对有症状的恶性疟原虫疟疾的免疫力的获得仍然不完全。这些观察结果表明，不同的免疫机制可能对于预防这些疟疾物种很重要。
In a treatment re-infection study of 206 Papua New Guinean school children, we examined risk of reinfection and symptomatic malaria caused by different Plasmodium species. Although children acquired a similar number of polymerase chain reaction-detectable Plasmodium falciparum and P. vivax infections in six months of active follow-up (P. falciparum = 5.00, P. vivax = 5.28), they were 21 times more likely to develop symptomatic P. falciparum malaria (1.17/year) than P. vivax malaria (0.06/year). Children greater than nine years of age had a reduced risk of acquiring P. vivax infections of low-to-moderate (> 150/mu L) density (adjusted hazard rate [AHR] = 0.65 and 0.42), whereas similar reductions in risk with age of P. falciparum infection was only seen for parasitemias > 5,000/mu L (AHR = 0.49) and symptomatic episodes (AHR = 0.51). Infection and symptomatic episodes with P. malariae and P. ovale were rare. By nine years of age, children have thus acquired almost complete clinical immunity to P. vivax characterized by a very tight control of parasite density, whereas the acquisition of immunity to symptomatic P. falciparum malaria remained incomplete. These observations suggest that different mechanisms of immunity may be important for protection from these malaria species.