Atopic Disease

This study is about allergic diseases in people living in Mali. Allergic diseases can cause health problems like asthma or skin rashes. In this study, the investigators will look for clues about things that may affect whether people get allergic diseases. The investigators will look at things on or in the body, like germs, and things in the environment, like pollution. To do this, the investigators will collect different types of biological samples, health information, and environmental information from people with allergic diseases and people without allergic diseases. The investigators will compare what is found in each group to look for differences that might be related to allergic disease.