MedDataX Logo

Community Dynamics of Malaria Transmission in Humans and Mosquitoes in Fleh-la and Marshansue, Salala District, Bong County, Liberia

NCT ID: NCT04704674

Last Updated: 2025-12-24

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

ACTIVE_NOT_RECRUITING

Total Enrollment

396 participants

Study Classification

OBSERVATIONAL

Study Start Date

2021-09-30

Study Completion Date

2026-02-28

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Background:

Malaria is a disease that affects many people in Liberia. It is caused by germs (parasites) that are spread by mosquito bites. Researchers want to gather data that may help them understand the best way to use a malaria vaccine in Liberia, which will be important in getting rid of the disease.

Objective:

To find out how often people of all ages who live in Fleh-la and Marshansue, Liberia, get malaria.

Eligibility:

Healthy people ages 6 months and older who live in Fleh-la and Marshansue in a household with adults and children.

Design:

Participants will be screened with a physical exam and questions about their health.

Participants will have monthly study visits. They will be asked about any symptoms of malaria and their use of bednets. Their vital signs, such as blood pressure and temperature, will be checked. Blood will be taken from the participant s arm or finger with a needle. If they have a fever, they will get a malaria test. If positive, they will get drugs to treat malaria.

Once a month, participants houses will be examined for mosquitoes. The team will remove all mosquitoes they collect. As part of this collection, participants houses will be sprayed with a chemical to kill mosquitoes and other insects. Participants will not be allowed in their house while the team is inside. The spray will not harm the participants.

Once a year, at the monthly visit, an additional blood sample will be taken.

Some of the participants blood samples will be used for genetic testing.

Participation will last for up to 3 years.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

A vaccine that interrupts malaria transmission is critical to eradicate the disease, but improved assays are needed to measure the efficacy of vaccines. Transmission-blocking vaccines (TBVs) work by inducing antibodies that inhibit parasite development in the mosquito interrupting transmission. Efficacy of vaccines may be estimated by in vitro membrane feeding assays using immune sera and laboratory mosquitoes, but qualified assays that measure transmission in the field are needed to assess transmission-blocking interventions in natura. Clinical trials of TBVs have started elsewhere on the continent in Mali, and we have planned to expand TBV studies here in Liberia soon. This protocol is already being used for a longitudinal cohort to gather information of malaria transmission based on the rates of blood smear positive individuals by month, season and year in Fleh-la and Marshansue, in Salala, Bong County, Liberia. Individuals in the villages were approached first for participation, including permission to contact their household and neighbors of their compound for participation. Households were identified using census data and individuals who consented for participation are being enrolled. Malaria smears are obtained at monthly visits, in conjunction with mosquito collections in/around village residences. Parasite infection rates in locally caught mosquitoes will be assessed longitudinally for differences by season and year. A total of 400 volunteers from Fleh-la and Marshansue will be enrolled. Participants will be followed for at least one year, to collect data that will guide the design of future community-based trials of TBV for which this amendment is being submitted for approval.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Malaria

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

Assays BLOOD SAMPLING Parasites Gametocyte Infection Natural History

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

COHORT

Study Time Perspective

PROSPECTIVE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

0.5 - 5 years

Age bracket for infants/children up to age five years

No interventions assigned to this group

10 - 18 years

Age bracket for children 10 - 18 years

No interventions assigned to this group

19 + years

Age bracket for adults over 19 years

No interventions assigned to this group

5 - 10 years

Age bracket for children ages 5 - 10 years

No interventions assigned to this group

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* 6 months of age and above
* Known resident of Fleh-la and Marshansue or the surrounding villages and planning to remain for duration of study
* Willingness to allow stored laboratory specimens to be used for future research
* Acceptance and signature of the written informed consent and the assent for children aged 12-17 years who are not otherwise emancipated


To be eligible for participation, households must meet the following criteria:

* Household with at least 3 residents eligible for participation.
* Household with at least one compound member who is below 18 years of age whose parents or caretakers are willing to provide informed consent for the child to participate.
* Household members willing to accommodate mosquito sampling in their compound, both indoors and outdoors.

Exclusion Criteria

* Behavioral, cognitive, or psychiatric disease that in the opinion of the investigator affects the ability of the subject to understand and cooperate with the study protocol.
* Other condition that, in the opinion of the investigator, would jeopardize the safety or rights of a volunteer participating in the trial or would render the subject unable to comply with the protocol.
Minimum Eligible Age

6 Months

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Institute of Allergy and Infectious Diseases (NIAID)

NIH

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Jennifer C Hume

Role: PRINCIPAL_INVESTIGATOR

National Institute of Allergy and Infectious Diseases (NIAID)

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

National Public Health Institute of Liberia (NPHIL)

Fleh-la, , Liberia

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Liberia

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

000158-I

Identifier Type: -

Identifier Source: secondary_id

10000158

Identifier Type: -

Identifier Source: org_study_id