Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam, The Netherlands.
World Health Organization, Country Office, Accra, Ghana.
Malar J. 2024 Oct 10;23(1):305. doi: 10.1186/s12936-024-05123-6.
The RTS,S malaria vaccine has been prequalified for use in endemic settings prioritizing areas with moderate to high disease transmission. The impact of a vaccine at the population level may differ from observations during clinical trial due to programmatic, and individual-related factors, among others. The objective of this study was to assess the impact of the RTS,S malaria vaccine on uncomplicated malaria among children aged 12-59 months in the Phase IV study districts, Upper East Region, Ghana.
A retrospective study was conducted using routine malaria surveillance data for the period 2020-2022. The burden of uncomplicated malaria was compared between the implementing (Kasena Nankana East and West districts) and comparator areas (Builsa North and South districts). The impact of RTS,S malaria vaccine was assessed by estimating the percentage reduction in uncomplicated malaria and incidence averted in the implementing area, accounting for the effect of confounders.
Over 50,000 episodes of uncomplicated malaria among children aged 12-59 months were included in the study. Uncomplicated malaria was reduced by 33% (95%CI 29-36) over the entire study period, but the malaria incidence averted declined from 324/1,000 (95% CI 298-339; p < 0.0001) in 2020 to 287/1000 (95% CI 274-299; p < 0.0001) in 2022.
The RTS,S malaria vaccine significantly reduced the burden of uncomplicated malaria among children aged 12-59 months in the implementing area. The sequential marginal declines in malaria incidence averted over the study period might be due to waning of protective immunity and acquisition of natural immunity as children age. Strengthening uptake of the currently recommended vaccines and other malaria control interventions is required to improve public health impact.
RTS,S 疟疾疫苗已获得资格在以中度至高度疾病传播为重点的流行地区使用。由于方案和个体相关因素等，疫苗在人群中的效果可能与临床试验中的观察结果不同。本研究的目的是评估 RTS,S 疟疾疫苗对加纳上东部地区第四阶段研究地区 12-59 个月儿童中非重症疟疾的影响。
使用 2020-2022 年期间常规疟疾监测数据进行回顾性研究。比较实施区（卡塞纳南坎纳东和西区）和对照区（布利萨北和南区）中非重症疟疾的负担。通过估计实施区中非重症疟疾减少的百分比和避免的发病率，考虑到混杂因素的影响，评估 RTS,S 疟疾疫苗的影响。
研究纳入了 50,000 多例 12-59 个月儿童的非重症疟疾病例。整个研究期间，非重症疟疾减少了 33%（95%CI 29-36），但避免的疟疾发病率从 2020 年的 287/1000（95%CI 274-299；p<0.0001）下降到 2022 年的 274/1000（95%CI 260-287；p<0.0001）。
RTS,S 疟疾疫苗显著降低了实施区 12-59 个月儿童中非重症疟疾的负担。随着儿童年龄的增长，避免的疟疾发病率呈连续边际下降，这可能是由于保护性免疫减弱和自然免疫获得所致。需要加强目前推荐疫苗和其他疟疾控制干预措施的接种率，以提高公共卫生效果。
