B50
Conditions
Interventions
Group 1: Study participants with asymptomatic Plasmodium falciparum (Pf) malaria defined as:
- Pf parasitaemia of 500 to 50,000 parasites/µL
- presence of Pf mono-infection
- absence of fever (axilla
After community-based pre-screening and full written informed consent by the participants, in- and exclusion criteria will be assessed according to the protocol. If eligible, participants will remain
Control volunteers will be recruited from surroundings of asymptomatic participants and will be admitted for sleep re
Sponsors
Centre de Recherches Médicales de Lambaréné
Eligibility
Sex/Gender
All
Age
18 Years to 59 Years
Inclusion criteria
Inclusion criteria: - Males or females, aged =18 years to <60 years - Malaria group: Asymptomatic malaria defined as: o Pf parasitaemia of 500 to 50,000 parasites/µL o presence of Pf mono-infection o absence of fever (axillary temperature <38.5 °C and absence of history of fever in the recent 72 hours) o no other symptoms related to malaria - Control group: healthy, negative for Plasmodium falciparum using microscopy, sex- and age-matched to malaria group - Willingness to stay at the sleep unit for up to 72 hours and follow the measurement protocol including standardized food intake - No consumption of prescribed or over-the-counter drugs for at least seven days before the study (except for hormonal contraception) - No consumption of psychoactive substances (e.g., cannabis, ibogaine) and sleep aids, and drugs that affect sleep (e.g., antihistamines) for at least seven days before the study - No consumption of beverages containing caffeine or alcohol for at least 24 hours before the study - Willingness to take part in the study documented by signed informed consent form
Exclusion criteria
Exclusion criteria: - Signs and symptoms of acute malaria (symptomatic participants will be treated by the team, but will not be included in the study) - Working shifts outside daytime working hours in the last four weeks before the study - Active tuberculosis, or history of taking anti-tuberculosis medications within 12 months prior to screening. - Known HIV, HBV and HCV infection - Loa loa or Mansonella perstans infection detected by thick blood smear microscopy - Taking an experimental drug in the last 4 weeks - Antimalarial treatment in the last 4 weeks - Use of systemic antibiotics with known antimalarial activity within 30 days of study enrolment (e.g. trimethoprim-sulfamethoxazole, doxycycline, tetracycline, clindamycin, erythromycin, fluoroquinolones, or azithromycin) - Moderate to severe anaemia (hemoglobin 2) - Participants with any psychiatric or neurological condition including substance abuse - Suspected or known current alcohol abuse as defined by an alcohol intake of greater than 60 g (men) or 40 g (women) per day - Any other finding which, in the opinion of the investigator, may significantly affect the ability to participate in the study or impair interpretation of the study data
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Correlations between sleep, immune and clinical endpoints | — |
Secondary
| Measure | Time frame |
|---|---|
| Sleep endpoints: 1. Duration and proportion of sleep stages as measured by polysomnography. 2. Spectral power and slow-wave activity (SWA) as assessed by electroencephalography (EEG) recordings. 3. Sleep quality measured by the Pittsburgh Sleep Quality Index (PSQI) and the Karolinska Sleep Questionnaire (KSQ), and daytime sleepiness assessed by the Epworth Sleepiness Scale (ESS) . 4. Rest-activity rhythms as assessed by actigraphy Immune endpoints: 1. (Poly)functional, (i.e., expressing IFN-?, IL-2, and/or TNF cytokines) Pf-specific CD4 and CD8 T cells will be assessed by flow cytometry following stimulation of thawed PBMCs with Pf-infected red blood cells. 2. B-cell response and functional characterization of subclasses and avidity of Pf-specific antibodies in serum 3. Plasma cytokines (such as TNF, IFN-?, IL-1, IL-4, IL-6 and IL-10) and chemokines (such as CXCL8, CXCL9, CCL4 and CCL5) in serum 4. Counts of leukocyte subsets (naïve, central memory, effector memory, and terminally-differentiated T cells) in thawed PBMCs 5. Transcriptional immune cell-specific signature in thawed PBMCs Clinical endpoints: 1. Parasite kinetics (peak parasitemia, area under the curve, time to <100 parasites/mL, parasite multiplication rate, gametocytaemia) 2. Fraction and time point of asymptomatic participants developing malaria symptoms, such as fever, chills, headache, arthralgia, myalgia and other non-specific symptoms 3. Neurobehavioral symptoms such as malaise, fatigue and impaired mood and cognition | — |
Countries
Gabon
Contacts
Public ContactJean-Claude Dejon Agobe
Centre de Recherches Médicales de Lambaréné
Outcome results
None listed