Blood-Stage Plasmodium Vivax Cell Bank

Background: Malaria is caused by a parasite (a type of germ called P. vivax) that is carried by mosquitoes. The disease is transmitted to people when they are bitten by infected mosquitoes. To make drugs and vaccines for malaria, researchers need malaria-infected blood. Plasmodium vivax cell cultures are currently not cultured in vivo, and thus establishing a blood bank from P. vivax infections will be vital for future research. Objective: The goal of this study is to infect people with early-stage malaria, then collect infected blood samples to store in a cell bank for future use. Eligibility: Healthy adults ages 18-50 who will not be living alone during the study period. Design: Participants will be screened with a physical exam, heart health test, and medical history. They will have blood and urine tests. They will take a mental health survey. They must pass an exam to prove they understand the study. Participants will have red blood cells infected with P. vivax injected into an arm vein. They will be observed for side effects. They will get a thermometer to measure their temperature at home. For the next 3 days, they will be monitored via phone call or text. Starting on day 4 after the infection, they will have daily study visits to give blood samples. They will likely develop symptoms of malaria, such as fever, chills, headache, and muscle pain. Participants will be admitted to the hospital for 2-3 days when either they develop symptoms or the daily blood tests detect a certain amount of parasites. Once malaria is confirmed, a sample of their blood will be collected for the cell bank. Then they will be treated for malaria with oral medication that will cure the infection. Those who do not develop malaria will begin treatment after 15 days. Participants will have follow-up visits 28 and 90 days after infection. Participation will last for 3-5 months.