Impact of Seasonal Malaria Chemoprevention on Immunity Against Malaria Among Children in Northern Benin

NCT ID: NCT05650502

Last Updated: 2022-12-28

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 440 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2021-06-01
• Study Completion Date: 2022-05-30

Brief Summary

This study aims to evaluate the effects of SMC (Seasonal malaria chemoprevention) with Sulfadoxine-Pyrimethamine (SP) and Amodiaquine (AQ) on the evolution of anti-malarial immunity of children and their susceptibility to malarial infection.

This is a cross-sectional study on children aged 6 to 59 months with/without SMC in two villages in northern Benin. Sociodemographic and clinical data as well as repeated blood samples will be collected from 440 children (before, during and after treatment). Samples will be analyzed using a Luminex assay to investigate antibody responses to MSP (merozoite surface protein) , Glurp (Glutamate-Rich Protein) and a panel of PfEMP1. qPCR (quantitative polymerase chain reaction) will be used to detect the prevalence of malaria at this period and parasites infecting children will be characterize during the follow up.

Detailed Description

Study location and population The study was conducted in parallel in two different sites, the health districts of Cobly and Tchaourou (two villages) located in northern Benin. These two districts have been chosen based on the Ministry of Health's programming for the implementation of SMC. The two sites were very similar in terms of malaria transmission characteristics and epidemiology, with the difference that SMC was implemented in Cobly but not in Tchaourou. Participants will be informed on the importance of SMC. A written informed consent was collected from parent or guardian of each child. Participation was entirely voluntary.

Study Design and procedures This is a case control study focuses on the follow-up over 12 months of children aged 6 to 59 months in northern Benin. The study was conducted in collaboration with National Malaria Control Program (NMCP). Demographic data generated by the NMCP had allow us for a random selection of children from random households. In both intervention and control sites, equal numbers of children were included. The study team visited each selected household to inform members. A monthly visit has been set up for monitoring. Children of consenting parents or guardians were recruited and parents/guardians were taken through a questionnaire administered by the researcher or an assistant (clinician). 1 ml of peripheral venous blood was collected into collection tubes and transferred to the Center for Expertise and Enhancing Research in Epidemiology and Public Health (CEEREPH) at the University of Parakou where a blood smear was prepared from each sample. Fifty microliters of blood have been transferred to Whatman 3MM filter paper and stored at room temperature for DNA extraction. The remaining whole blood have been centrifuged. The plasma and red blood cells were aliquoted. Samples was collected at 4 times during the 12 months follow-up period. The first samples were collected at the beginning of SMC implimentation (before children receive the first SMC dose), the second blood sample were collected at the day of the third dose of SMC, the third, at three month after the last dose of SMC and the fourth, six months after the last dose of SMC).

Malaria prevalence Thick and thin blood smears whave been prepared from all samples at all four times. Thick smears will be fixed in methanol. All slides were air dried and stained using Giemsa stain 3% for 45-60 min. Once dry, the stained thick and thin blood films were examined microscopically using a routine procedure. Parasite densities was recorded as the number of parasites/μl of blood assuming an average leukocyte count of 8,000/μl of blood. Dried blood spots were air dried and stored individually in small Ziploc bags with a desiccant. Plasmodium spp detection was performed using a real time polymerase chain reaction (qPCR).

Anti-PfEMP1 antibody response Plasmodium falciparum-encoded variant surface antigens (VSA) are expressed on the surface of infected erythrocytes (IE) and mediate binding to a range of endothelial cell receptors. The best characterized VSA are the var gene-encoded P. falciparum erythrocyte membrane protein 1 (PfEMP1) family in two exon units. Exon I codes for the extracellular and variable part of the protein as well as a transmembrane region and Exon II encodes the intracellular and relatively conserved acidic terminal segment (ATS). The most variable part of the protein contains a N-terminal segment followed by segments composed of three domain types; Duffy binding-like domains (DBL-domains): Cysteine-rich inter-domain regions (CIDRs) and C2. In this study, a panel of plasma antibody was quantified using microsphere bead-coupled proteins comprising 28 P. falciparum-derived antigens and tetanus toxoid, using the Luminex platform. The panel includes VAR2CSA (the VSA associated to placental malaria) and 25 HIS-tagged CIDR proteins representing all three main groups of PfEMP1, merozoite surface protein 1 (MSP1) and apical membrane antigen 1 (AMA1).

Conditions

Plasmodium Malariae Infection; SMC; Immune System Disease

Keywords

Seasonal malaria chemoprevention; Malaria; Children; Anti PfEMP1

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: OTHER

Study Groups

ISC (ISAMIMA children group-Cobly)

This group included children from 6 to 59 months living in Cobly and receiving the SMC treatment. The treatment is administered for three consecutives days for 4 months (from july to october).

For children under 12 months: one dose of SP 250/12.5mg on day 1 AQ 75mg once daily for 3 days For children from 12 to 59 months: one dose of SP 500/25mg on day 1 AQ 150 mg once daily for 3 days A monthly visit was planned for monitoring during the follow up. Sample was collected in jun, september, january and April.

saisonal malaria chimoprevention

Intervention Type: DRUG

Investigate the impact of saisonal malaria chimoprevention on children anti PfEMP1 construction and maintenance and their succeptibility to malaria infection

IST (ISAMIMA children group-Tchaourou)

This group included children from 6 to 59 months living inTchaourou and who did not receiving the SMC treatment.

A monthly visit was planned for monitoring during the follow up. Sample was collected in jun, september, january and April.

saisonal malaria chimoprevention

Intervention Type: DRUG

Investigate the impact of saisonal malaria chimoprevention on children anti PfEMP1 construction and maintenance and their succeptibility to malaria infection

Interventions

saisonal malaria chimoprevention

Investigate the impact of saisonal malaria chimoprevention on children anti PfEMP1 construction and maintenance and their succeptibility to malaria infection

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• Aged between 6 and 59 months
• Have been selected and accepted to receive SMC treatment (SP-AQ) in the intervention site and not in the control site
• Be able to take drugs

Exclusion Criteria

• Child whose parents will no longer consent at some point in the study for one reason or another
• Children suffering from a chronic disease
• Intolerance to certain drugs

• Minimum Eligible Age: 6 Months
• Maximum Eligible Age: 59 Months
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Institut de Recherche pour le Developpement

OTHER_GOV

Sponsor Role: collaborator

University of Copenhagen

OTHER

Sponsor Role: collaborator

University of Ghana

OTHER

Sponsor Role: collaborator

Institut de Recherche Clinique du Bénin (IRCB)

UNKNOWN

Sponsor Role: collaborator

Hôpital Cochin

OTHER

Sponsor Role: collaborator

Université de Parakou

OTHER

Sponsor Role: lead

Responsible Party

Azizath Moussiliou

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Nicaise TIUKUE NDAM, Professor

Role: STUDY_CHAIR

Institut régional de développement IRD (UMR261)

Adrian LUTY, Professor

Role: STUDY_CHAIR

Institut régional de développement IRD (UMR261)

Locations

Azizath MOUSSILIOU

Parakou, , Benin

Countries

Benin

Other Identifiers

University of Parakou

Identifier Type: -

Identifier Source: org_study_id