MedPath

Age of Exposure and Immunity to Malaria in Infants

Not Applicable
Completed
Conditions
Malaria
Interventions
Registration Number
NCT00231452
Lead Sponsor
Hospital Clinic of Barcelona
Brief Summary

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.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
349
Inclusion Criteria

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.
Exclusion Criteria

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).

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Late exposure groupSulfadoxine-pyrimethamine (SP) + Artesunate (AS)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.
Early exposure groupSulfadoxine-pyrimethamine (SP) + Artesunate (AS)Participants received monthly placebo from 2.5-4.5 months of age and monthly SP+AS from 5.5-9.5 months of age.
Control groupSulfadoxine-pyrimethamine (SP) + Artesunate (AS)Participants received monthly placebo from 2.5 to 9.5 months of age.
Primary Outcome Measures
NameTimeMethod
(Clinical) Time to first or only episode of clinical malaria in the second year of life detected by passive case detectionfrom 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.

Secondary Outcome Measures
NameTimeMethod
(Clinical) Time to first or only episode of malaria (using other case definitions), anaemia and other clinical endpoints.12 to 24 months of age

Global comparison between the 3 study groups of the time to first or only episode of clinical malaria (according to the secondary case definitions) in the second year of follow up detected by passive case detection. Other endpoints include multiple episodes of malaria, time to first or only episode of anaemia, total hospital visits and prevalence of parasitaemia and anaemia at different time points. In addition, pairwise comparisons of the 3 groups are also presented.

Oxidative stress markersmultiple time points during the first two years of life (2.5, 5.5, 10.5, 15 and 24 months of age)

Quantification of the antioxidant/pro-oxidant status over the first two years of life in relation to age of first exposure to infection.

Humoral and cellular immune responsesmultiple time points during the first two years of life (2.5, 5.5, 10.5, 15 and 24 months of age)

Quantification of antibody and cytokine responses to P. falciparum protein antigens and toxins over the first two years of life in relation to age of first exposure to infection

Host genetics2.5 months of age

Analysis of haematological genetic factors, polymorphisms in genes involved in inflammatory or immunological responses to malaria and polymorphisms in genes involved in the Th1/Th2 immunological pathway.

Trial Locations

Locations (1)

Centro de Investigaçao em Saude da Manhiça

🇲🇿

Manhiça, Maputo, Mozambique

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