Following the decline of malaria in Sub-Saharan Africa, clinicians face febrile patients in whom an alternative diagnosis has to be made. This situation has led to an overuse of antibiotics by clinicians. It is crucial to increase knowledge on etiologies and risk factors of outpatient febrile illness in order to improve their management.

This present proposal aims to investigate the etiologies of fever among adult patients attending an outpatient department in urban Tanzania. It also aims to assess the clinical significance of nasopharyngeal (NP) respiratory viruses and bacteria documentation in this setting. Third, it aims to compare the spectrum of infections in this population with that of children included in the same setting in a previous study. The last objective is to assess diabetes mellitus (DM) as a risk factor for infection and exposure to indoor air pollution (IAP) as a risk factor for acute respiratory infections (ARI) in adults in Tanzania.

The investigators hypothesize that acute respiratory infections are the main cause of adult febrile illness in a urban low-income setting and that use of quantitative molecular assays on naso-oropharyngeal samples can improve the diagnosis of pneumonia. The investigators also think that the spectrum of infections is different between children and adults, mainly due to a high HIV prevalence in adults. The investigators also hypothesize that experiencing IAP and/ or DM is a risk factor for infections in adults.

Inclusion Criteria:

• Temperature >=38°C
• History of fever for less than 8 days
• First consultation for the present problem

Exclusion Criteria:

• Refusal of HIV screening
• Main complaint is injury or trauma
• Antibiotic treatment in the last 7 days
• Within 6 weeks after delivery
• Hospitalization during the last month

Every consecutive adult with temperature ≥38°C attending the outpatient department of Mwananyamala Hospital will be screened for inclusion. Additional inclusion criteria are fever of ≤1 week duration and first consultation for the present problem. Exclusion criteria are refusal of HIV screening, main complaint is injury or trauma, antibiotic treatment during the previous week (apart from cotrimoxazole prophylaxis), delivery within the previous 6 weeks and hospitalization during the last month. Medical history will be taken (including exposure to IAP) and clinical examination will be done in a standardized way.