Preventing the Spread of Malaria in Mali
- The Malaria Research and Training Center in Mali is involved in research to make a malaria vaccine. The vaccine is being designed to help interrupt the spread of malaria. Researchers want to study the different tests that can determine whether these vaccines will block the development of malaria parasites in the mosquito. To help develop these vaccines, researchers are studying children and adults from a village in Mali. They want to see whether the area will be a good place to test the malaria blocking vaccine in the future.
- To study different tests of malaria spread and malaria blocking vaccines.
- To see how many people in the Mali village have malaria parasites in their blood that can infect other people.
- Healthy people between 3 months and 50 years of age who live in a Mali village.
- Participants will have a physical exam and medical history. They will give a blood sample that will be tested for malaria parasites. Participants who have malaria in the blood that can be transmitted to others will have more blood tests.
- All participants will have regular blood tests and checkups to see if malaria parasites have grown. Their response to malaria infections and treatments will also be tested.
- Participants at least 5 years of age will have tests that involve being bitten by laboratory-grown mosquitoes. These insects have never been infected with malaria or other diseases. Researchers will study the effectiveness of different vaccines meant to block the spread of malaria.
- Researchers may collect mosquitoes from participants' houses to see if these mosquitoes have bitten someone nearby. They will try to learn more about what makes mosquitoes more likely to become infected with malaria when they bite someone. Researchers may also map the house to study the areas where malaria infection is more common.
- Participants will be followed for up to 1 year.
|Study Design:||Time Perspective: Prospective|
|Official Title:||Malaria Transmission Blocking Assay Development and Gametocyte Carriage in a Vaccine Testing Site in Mali|
|Study Start Date:||April 2011|
A vaccine which interrupts malaria transmission is a critical tool to achieve the ultimate goal of eradication of this disease. Transmission blocking vaccines work by inducing antibody in vaccinated individuals that inhibits the development of malaria parasites in the mosquito, thus interrupting the cycle of transmission to the next human host. Efficacy of these vaccines may be estimated by in vitro membrane feeding assays using immune sera and laboratory strain mosquitoes, but these assays need to be qualified to determine to what extent they are predictive of transmission blocking in the field. Clinical trials of transmission blocking vaccines are also anticipated, and data are needed to determine target populations and sample sizes. This protocol will use a nested case-control cohort design to compare results of mosquito feeding assays in a malaria exposed population in Bancoumana and surrounding villages in, Mali. Households will be identified using census data and individuals will be consented for participation. Malaria smears will be obtained at monthly visits, and gametocytemic individuals and age-matched gametocyte negative individuals will be asked to participate in direct feed experiments using insectary-raised mosquitoes. Infectivity in these mosquitoes will be compared against those of mosquitoes fed in membrane feeding assays in Mali and the USA. Data will also be obtained on gametocyte carriage rates through the year. A total of 250 volunteers from Bancoumana, ages 3 months to 50 years, were enrolled in 2011. In 2012, an additional 250 adults from Bancoumana were enrolled and participants older than 5 years of age were continued. A transmission blocking vaccine trial started in May 2013, and had enrolled participants from the adult cohort in this study. Up to 50 adults from Bancoumana and surrounding villages will be enrolled in 2013.
|University of Bamako, Faculty of Medicine, Pharmacy and Odontostomatology|
|Principal Investigator:||Yimin Wu, Ph.D.||National Institute of Allergy and Infectious Diseases (NIAID)|