Diagnostic biologique de la dengue

Dengue is the most important disease caused by an arbovirus worldwide. Its clinical manifestations are very large from asymptomatic infections to severe diseases with fatal outcome. No effective antiviral treatment or vaccine is available. Thus, a rapid and accurate diagnosis is of paramount importance both for better clinical case management and surveillance. Diagnosis methods depend on the time clinical signs appeared. Within the 7 first days of fever, direct tests are preferred. RT-PCR methods are sensitive, specific, and can identify viral serotypes. Conventional RT-PCR will probably be replaced by real time PCR as soon as standardised and accurate assays for the four serotypes will be available. Serology (EIA) is used only after 7 days of disease, i.e. late in the course of dengue; it is accurate, specific but not discriminatory for serotypes and high cross-reactive. NS1 antigen detection still lack of clinical sensitivity and viral isolation is too fastidious. Even though ameliorations are necessary, viral detection by RT-PCR remains the best tool in clinical settings for a rapid diagnosis of severe dengue infections.