Epidemiology and Clinical Characteristics of Emerging and Re-emerging Infectious Diseases With Epidemic Potential in Mali

Participants referred or managed by the National Disease Surveillance Committee, primary healthcare facilities, level-3 hospitals, or other facilities Adults and children of any age Unexplained fever (temperature greater than or equal to 38°C), recorded or reported, within 24 to 48 hours, regardless duration with at least one of the following signs or symptoms: * Unexplained bleeding * One or more generic symptoms (headache, tiredness, myalgia, arthralgia, diarrhea, anorexia, weight loss, rash) * Jaundice * One or more respiratory symptoms (cough, dyspnea, pharyngitis, rhinorrhea) * Guillain-Barré syndrome * Newborns with microcephaly or other brain defects * Agree to have samples collected and stored for further studies Exclusion criteria \- Participants may be excluded from enrolling in the study if they have any known medical disorders or other circumstances which, in the opinion of the investigator, might make participation unsafe or difficult (e.g. inability to obtain necessary samples, mental illness).