Markers of T Cell Suppression: Antimalarial Treatment and Vaccine Responses in Healthy Malian Adults

Background: People with malaria often show altered immune responses to many illnesses and vaccines. This means that the malaria might cause immune suppression. It is not clear how or which vaccines are impacted by malaria. It is also not clear if the impacts are such that people should be preemptively treated before they get vaccinations. Researchers want to see if there is a link between taking an antimalaria drug prior to getting vaccines and the immune response to those vaccines. To do this, they will study people who are taking part in certain NIAID studies. Objectives: To compare the proportion of PD1+ CD4 T cells among all T cells in vaccine immune responses in adults who have or have not received antimalarials prior to getting a Menactra vaccine. Eligibility: Healthy Malian adults who: Were previously enrolled in NIAID Protocol 13-I-N109 or 15-I-0044 Reside in Bancoumana and neighboring villages Are not pregnant Design: Participants will be screened with a physical exam. Participants will get the vaccines listed below as part of Protocol 13-I-N109 or 15-I-0044. This study will follow their schedule. At each visit, participants will give a blood sample. They will also have a physical exam. Each visit will last 1 to 2 hours. At visit 1, participants will get a hepatitis vaccine. Two weeks later, participants may get the antimalarial drug Coartem . They will be chosen at random. Two weeks later, participants will get Menactra . Participants will have 5 follow-up visits after they get Menactra . The study will last up to 4 months. ...