This study will examine the natural history of Leishmanial infections and their treatments. It will provide an opportunity for NIAID staff to learn more about leishmaniasis and perhaps to improve diagnostic tests for these infections.

The purpose of this study is to see if fecal microbiota transplantation (FMT) can reduce inflammation in the colon.

The purpose of this study is to evaluate whether Mozobil is safe and effective to treat neutropenia (low white blood cell count) in patients with WHIMS and to determine an appropriate treatment dose of Mozobil, within currently approved dosage levels.

The purpose of this study is to see if signs of inflammation in CSF help predict a persons response to different drugs.

The purpose of this study is to test samples from people with a Primary immunodeficiency disorders (PIDs) or people related to someone with a PID to find out what causes PIDs.

The objective of this study is to collect samples and data from individuals who have been exposed to or have contracted viral infections.

The purpose of the study is to characterize the immune responses during and after SARS-CoV-2 infection and determine if there is any relationship to clinical course and outcome.

The objective of this study is to collect blood and other samples to study the natural history of tuberculosis.

The purpose of this study is to use digital devices to collect data from participants in challenge studies that could indicate subtle changes in health during an infection that might otherwise go unnoticed.

This study will compare tests performed on both healthy volunteers and individuals who have signs or symptoms of immune-related damage to their central nervous system (CNS).