Data from: Modeling the dynamics of Plasmodium vivax infection and hypnozoite reactivation in vivo

The dynamics of Plasmodium vivax infection is characterized by reactivation of hypnozoites at varying time intervals. The relative contribution of new P. vivax infection and reactivation of dormant liver stage hypnozoites to initiation of blood stage infection is unclear. In this study, we investigate the contribution of new inoculations of P. vivax sporozoites to primary infection versus reactivation of hypnozoites by modeling the dynamics of P. vivax infection in Thailand in patients receiving treatment for either blood stage infection alone (chloroquine), or the blood and liver stages of infection (chloroquine + primaquine). In addition, we also analysed rates of infection in a study in Papua New Guinea (PNG) where patients were treated with either artesunate, or artesunate + primaquine. Our results show that up to 96% of the P. vivax infection is due to hypnozoite reactivation in individuals living in endemic areas in Thailand. Similar analysis revealed the around 70% of infections in the PNG cohort were due to hypnozoite reactivation. We show how the age of the cohort, primaquine drug failure, and seasonality may affect estimates of the ratio of primary P. vivax infection to hypnozoite reactivation. Modeling of P. vivax primary infection and hypnozoite reactivation provides important insights into infection dynamics, and suggests that 90–96% of blood stage infections arise from hypnozoite reactivation. Major differences in infection kinetics between Thailand and PNG suggest the likelihood of drug failure in PNG.

间日疟原虫（Plasmodium vivax）感染的动力学特征为休眠子（hypnozoite）在不同时间间隔内发生复燃。目前尚不明确新发间日疟原虫感染与肝内休眠阶段休眠子的复燃，对血液阶段感染起始的相对贡献。本研究通过对泰国患者的间日疟原虫感染动力学进行建模，探究了新发间日疟原虫子孢子（sporozoite）接种所致原发性感染，与休眠子复燃各自的贡献占比；纳入研究的泰国患者仅接受血液阶段感染治疗（氯喹，chloroquine），或同时接受血液与肝脏阶段感染治疗（氯喹+伯氨喹，chloroquine + primaquine）。此外，我们还分析了巴布亚新几内亚（PNG）一项研究中的感染率，该研究纳入的患者分别接受青蒿琥酯（artesunate）单药治疗，或青蒿琥酯+伯氨喹联合治疗。研究结果显示，在泰国疟疾流行区居民中，高达96%的间日疟原虫感染源于休眠子复燃。类似分析表明，巴布亚新几内亚队列中约70%的感染由休眠子复燃引起。本研究还阐明了队列年龄、伯氨喹药物失效以及季节性因素，如何影响间日疟原虫原发性感染与休眠子复燃之比的估算结果。对间日疟原虫原发性感染与休眠子复燃的建模研究，为感染动力学提供了重要见解，并表明90%~96%的血液阶段感染源于休眠子复燃。泰国与巴布亚新几内亚之间感染动力学的显著差异，提示巴布亚新几内亚存在伯氨喹药物失效的可能性。