Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning, 530028, China.
Brown School, Washington University, St. Louis, MO, USA.
Malar J. 2023 Jul 13;22(1):209. doi: 10.1186/s12936-023-04642-y.
The global battle against malaria is facing formidable challenges, particularly in controlling Plasmodium vivax and Plasmodium ovale, whose cases have not been reduced as effectively as Plasmodium falciparum because of their relapse. This study investigates the current situation and underlying factors contributing to relapse or recrudescence of imported cases of P. vivax and P. ovale, and seeks to provide a reference for reducing relapse or recrudescence in malaria-free areas and offers a scientific basis for designing strategies to prevent imported re-transmission.
This study analysed imported P. vivax and P. ovale in Anhui, Zhejiang, Henan, Hubei, and Guangxi provinces during 2014-2021 by retrospective analysis. A case-control study was conducted on patients who experienced relapse or recrudescence.
From 2014 to 2021, 306 cases of P.vivax and 896 cases of P.ovale were included in the study, while 75 cases had relapse or recrudescence, including 49 cases of P. ovale (65.33%) and 26 cases of P. vivax (34.67%). Within less than 5 weeks after returning to the country, 122 cases of P. vivax (39.87%, 122/306) and 265 cases of P. ovale (29.58%, 265/896) occurred. Within less than 53 weeks, the ratio of P. vivax was 94.77% (290/306), and that of P. ovale was 89.96% (806/896). Among the cases experiencing relapse or recrudescence, only 1 case of P. vivax (1/26 3.85%) and 3 cases of P. ovale (3/49 6.12%) occurred within less than 5 weeks after the first onset, whereas 21 cases of P. vivax (21/26 80.77%) and 42 cases of P. ovale (42/49 85.71%) occurred within less than 53 weeks after the first onset. The difference in relapse or recrudescence due to different drugs and medication regimens and medical activities at various levels of medical institutions was statistically significant.
In areas where malaria has been eliminated, routine health screening in a scientific time frame for people returning from at-risk areas can effectively improve the efficiency of preventing re-transmission, thereby reducing prevention costs and disease burden. Preventing patients from self-treating and strengthening medication regulations in health facilities are key measures to reduce relapse or recrudescence.
全球疟疾防治工作面临严峻挑战，特别是在控制间日疟原虫和卵形疟原虫方面，由于其复发，病例并未像恶性疟原虫那样得到有效减少。本研究旨在调查间日疟原虫和卵形疟原虫输入性病例复发或再燃的现状及相关因素，为减少无疟疾地区的复发或再燃提供参考，并为制定策略预防输入性再传播提供科学依据。
采用回顾性分析方法，对 2014-2021 年安徽、浙江、河南、湖北和广西 5 省（自治区）报告的输入性间日疟原虫和卵形疟原虫病例进行分析。对复发或再燃病例进行病例对照研究。
2014-2021 年共纳入 306 例间日疟原虫和 896 例卵形疟原虫病例，其中 75 例出现复发或再燃，包括 49 例卵形疟原虫（65.33%，49/75）和 26 例间日疟原虫（34.67%，26/75）。在回国后不到 5 周内，发生 122 例间日疟原虫（39.87%，122/306）和 265 例卵形疟原虫（29.58%，265/896）。在不到 53 周内，间日疟原虫的比例为 94.77%（290/306），卵形疟原虫的比例为 89.96%（806/896）。在复发或再燃病例中，只有 1 例间日疟原虫（1/26，3.85%）和 3 例卵形疟原虫（3/49，6.12%）在首次发病后不到 5 周内发生，而 21 例间日疟原虫（21/26，80.77%）和 42 例卵形疟原虫（42/49，85.71%）在首次发病后不到 53 周内发生。不同药物和用药方案以及各级医疗机构医疗活动导致复发或再燃的差异有统计学意义。
在消除疟疾地区，对来自高风险地区的人群进行科学时间框架的常规健康筛查，可以有效提高预防再传播的效率，从而降低防控成本和疾病负担。防止患者自行治疗和加强医疗机构的用药规范是减少复发或再燃的关键措施。
