Microbiome and Atopy in Mali

Inclusion Criteria (Study Group): * Aged ≥3 years. * Able to provide informed consent (for ages ≥18 years) or has a parent or guardian who can provide informed consent on their behalf (for ages \<18 years). * Positive Screening questionnaire for asthma or eczema. * Diagnosed with atopic dermatitis or asthma via physician diagnosis and criteria as follows: * Clinical diagnosis of atopic disease, as defined by Hanifin and Rajka criteria, that has been present for ≥3 months before the screening visit. Inclusion Criteria (Healthy Volunteers): * Aged ≥3 years. * Able to provide informed consent (for ages ≥18 years) or has a parent or guardian who can provide informed consent on their behalf (for ages \<18 years). * Negative Screening questionnaire for asthma and eczema. * In good general health as evidenced by medical history and not diagnosed with atopic dermatitis or asthma via physician diagnosis. * Failure to meet Hanifin and Rajka criteria and \<3 on GINA guidelines for asthma diagnosis. * No self-reported history of food allergy. Exclusion Criteria: * Use of antibiotics in the 3 months prior to screening. * Current pregnancy or lactation (determined by self-report). * Treatment with an investigational drug within 12 months prior to screening. * Current smoker or tobacco use within 4 months prior to screening. * Current skin infections other than atopic dermatitis (e.g., scabies). * Active diarrhea as defined by three or more loose stools per day (Bristol stool scale score of 6 or 7). * Presence of current bacterial, viral, or fungal infection, with the exception of isolated onchomycosis, which is not exclusionary. * Any other condition or factor that the investigator determines may significantly influence the results of testing.