Age of Exposure and Immunity to Malaria in Infants
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 349
- 试验地点
- 1
- 主要终点
- (Clinical) Time to first or only episode of clinical malaria in the second year of life detected by passive case detection
研究概览
简要总结
The overall objective is to evaluate the effect of exposure to Plasmodium (P.) falciparum erythrocytic stage antigens during different periods of infancy on the development of naturally acquired immunity (NAI).
Hypothesis: Exposure to P. falciparum prior to 5 months of age does not result in the development of NAI, while exposure to P. falciparum after 5 months of age leads to the development of NAI. The risks of clinical malaria and anaemia during the second year of life will be compared between cohorts, as well as their correlations with the type and quality of immune responses (antibodies to several P. falciparum antigens, cytokines), oxidative stress markers and host genetic factors. These results should shed light on the determinants of the development of anti-P. falciparum responses early in life and the potential constraints to early life immunisation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- — 至 1 Week（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Inclusion criteria for pregnant women:
- •Healthy HIV-negative pregnant females less than 50 years of age who attend the voluntary counseling and testing (VCT) center at the Maragra or Manhiça antenatal clinic,
- •Permanent residents of the Manhiça area and expecting to be living in the area with their infant for at least 2 years.
- •Inclusion criteria for newborn infants:
- •Healthy infants, weighing >= 2 kg and having an alive mother.
排除标准
- •Exclusion criteria for pregnant women:
- •Plan to leave the area in less than 2 years from the start of the study;
- •Women not willing to get tested for HIV infection at the VCT center;
- •Test positive for HIV;
- •Not willing to provide informed consent;
- •Cannot understand either Portuguese or Changana (consent forms are written in these languages).
- •Exclusion criteria for newborn infants:
- •Any obvious congenital malformation;
- •Any signs of cerebral asphyxia;
- •Any obvious neonatal infection;
- •Same gender Twins;
- •Low birth weight (<2 kg).
研究组 & 干预措施
Late exposure group
Participants received monthly Sulfadoxine-Pyrimethamine (SP) plus Artesunate (AS) from 2.5-4.5 months of age and monthly placebo from 5.5-9.5 months of age.
干预措施: Sulfadoxine-pyrimethamine (SP) + Artesunate (AS) (Drug)
Early exposure group
Participants received monthly placebo from 2.5-4.5 months of age and monthly SP+AS from 5.5-9.5 months of age.
干预措施: Sulfadoxine-pyrimethamine (SP) + Artesunate (AS) (Drug)
Control group
Participants received monthly placebo from 2.5 to 9.5 months of age.
干预措施: Sulfadoxine-pyrimethamine (SP) + Artesunate (AS) (Drug)
结局指标
主要结局
(Clinical) Time to first or only episode of clinical malaria in the second year of life detected by passive case detection
时间窗: from 12 to 24 months of age
Global comparison between the 3 groups of the time to first or only episode of clinical malaria (according to the primary case definition) in the second year of follow up detected by passive case detection in the According-To-Protocol cohort. In addition, pairwise comparisons of the 3 groups are also presented.
次要结局
- (Clinical) Time to first or only episode of malaria (using other case definitions), anaemia and other clinical endpoints.(12 to 24 months of age)
- Oxidative stress markers(multiple time points during the first two years of life (2.5, 5.5, 10.5, 15 and 24 months of age))
- Humoral and cellular immune responses(multiple time points during the first two years of life (2.5, 5.5, 10.5, 15 and 24 months of age))
- Host genetics(2.5 months of age)