1University of Botswana, Department of Biological Science, Gaborone, Botswana.
2University of Namibia School of Medicine, Windhoek, Namibia.
Am J Trop Med Hyg. 2021 May 3;104(6):2159-2164. doi: 10.4269/ajtmh.21-0083.
In 2016, we reported the presence of Plasmodium vivax in Botswana through active case detection. A real-time PCR was used during a similar study in 10 districts to assess changes in the P. vivax prevalence. We assessed 1,614 children (2-13 years of age) for hemoglobin (Hb; g/dL) and Plasmodium parasites. The median age of all participants was 5.0 years (25th percentile, 3 years; 75th percentile, 8 years). The median Hb (g/dL) level was 12.1, but 18.3% of the participants had anemia (Hb < 11.0 g/dL); these participants were clustered in the younger than 5 years age group in all districts (P < 0.001). The risk of anemia decreased with age 5 years or older (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.197-0.34; P < 0.001). The prevalence rates of Plasmodium parasites were as follows: P. vivax, 12.7%; P. falciparum, 12.7%; P. malariae, 0.74%; and P. ovale (P. ovale curtisi), 0.68%. Mixed infection rates were as follows: P. falciparum and P. vivax, 2.35%; P. falciparum and P. ovale curtisi, 0.56%; P. vivax and P. malariae, 0.06%; and P. falciparum and P. malariae, 0.68%. The infections were largely asymptomatic (99.6%). Using logistic regression, the risk of infection with P. vivax was highest in Kweneng East (OR, 6.2; 95% CI, 2.9-13.1), followed by South East (OR, 5.6; 95% CI, 2.5-12.3) and Ngami (OR, 5.1; 95% CI, 2.2-12.0). Compared to the risk of infection for children younger than 5 years, the risk of infection decreased for children 5 years or older in regions with high rates of P. vivax and P. falciparum infections. P. vivax and P. falciparum have expanded within the asymptomatic population in Botswana; therefore, careful attention is required for their elimination.
2016 年，我们通过主动病例检测报告了博茨瓦纳存在间日疟原虫。在 10 个地区进行的一项类似研究中使用了实时聚合酶链反应来评估间日疟原虫患病率的变化。我们评估了 1614 名儿童（2-13 岁）的血红蛋白（Hb；g/dL）和疟原虫寄生虫。所有参与者的中位年龄为 5.0 岁（25%分位数为 3 岁；75%分位数为 8 岁）。中位 Hb（g/dL）水平为 12.1，但 18.3%的参与者患有贫血症（Hb<11.0 g/dL）；这些参与者在所有地区都集中在 5 岁以下年龄组（P<0.001）。贫血症的风险随着年龄 5 岁或以上而降低（比值比[OR]，0.26；95%置信区间[CI]，0.197-0.34；P<0.001）。疟原虫寄生虫的流行率如下：间日疟原虫，12.7%；恶性疟原虫，12.7%；卵形疟原虫，0.74%；和疟原虫（卵形疟原虫 curtisi），0.68%。混合感染率如下：恶性疟原虫和间日疟原虫，2.35%；恶性疟原虫和卵形疟原虫 curtisi，0.56%；间日疟原虫和卵形疟原虫，0.06%；恶性疟原虫和卵形疟原虫，0.68%。感染基本上是无症状的（99.6%）。使用逻辑回归，感染间日疟原虫的风险在东库内内（OR，6.2；95%CI，2.9-13.1）最高，其次是东南（OR，5.6；95%CI，2.5-12.3）和纳米（OR，5.1；95%CI，2.2-12.0）。与 5 岁以下儿童的感染风险相比，高间日疟原虫和恶性疟原虫感染地区 5 岁或以上儿童的感染风险降低。间日疟原虫和恶性疟原虫已在博茨瓦纳无症状人群中传播；因此，需要密切关注以消除这些疾病。
