Correlating Protection Against Malaria With Serum Profiles Against Plasmodium Falciparum Antigen Repertoires

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT01214876

Enrollment

500

Registered

2010-10-05

Start date

2010-08-31

Completion date

2011-03-31

Last updated

2011-03-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hiv Infection, Malaria, Schistosomiasis

Brief summary

A longitudinal study on immune responses in relation to protection against clinical malaria episodes will be conducted in Apac District, Uganda. Three cohorts will be recruited: children 1 to 5 years of age (n=250), children 6 to 10 years of age (n=125) and adults 25 and above (n=125). After finger prick sampling (\ 300µL) and examination at enrolment, participants will be followed up for one year. Follow-up will include fortnightly active case detection and three-monthly cross-sectional surveys. Clinical malaria attacks and the associated clinical and parasitological parameters will be related to immunological profiles determined utilizing a protein microarray as a capture substratum to profile the humoral immune response against a vast number of parasite antigens. For individuals who experience a clinical malaria attack or who are diagnosed with high density parasitaemia (≥15,000 parasites/µL) during cross-sectional surveys, a 5mL blood sample is obtained to determine the diversity of parasite antigens in the population in relation to antigen recognition in the cohort.

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

1 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* age 1-5 years, 6-10 years or 25 yearsand above * written informed consent must be given * the individual must have been resident of the area since birth or for a minimum period of two years * the individual must be willing to submit required information and to participate in repeated sampling (total blood volume \ 2.5 mL over a period of 12 months) * Absence of danger signs (as defined by WHO) or clinical features of AIDS. An HIV-test will be offered to all participants at enrolment and completion of the study.

Exclusion criteria

* unwillingness to sign consent form * unwillingness to reside in the study area during the follow-up period

Design outcomes

Primary

Measure	Time frame	Description
Immune correlates of protection against clinical malaria episodes with plasmodium falciparum	—	IMMUNE RESPONSES: protein array. CLINICAL MALARIA EPISODES: (reported) fever with i) P. falciparum parasites; ii) ... at a density \>=5,000 parasites/ul; iii) ... at a density \>=10,000 parasites/ul IMMUNOLOGICALLY PROTECTED INDIVIDUALS: parasitaemic during follow-up without reporting to the health facility with indicators of a clinical malaria episode

Secondary

Measure	Time frame	Description
Geographical patterns in malaria morbidity	—	Households are geo-located by GPS and hotspots of malaria transmission will be determined and related to serological profiles.
Asymptomatic parasite carriage and immune responses in different age-groups exposed to intense malaria transmission	—	ASYMPTOMATIC PARASITE CARRIAGE will be confirmed by microscopy and PCR.

Countries

Uganda

Outcome results