Duration of Zika Viremia in Serum

International audienc

Concurrent Dengue and Malaria in Cayenne Hospital, French Guiana

Dengue–malaria co-infection reports are scarce. Of 1,723 consecutive febrile patients in Cayenne Hospital, 238 had dengue (174 early dengue fever cases) and 393 had malaria (371 acute malaria); 17 had both. Diagnosis of 1 of these 2 infections should not rule out testing for the other infection

Kinetics of Zika Viral Load in Semen

International audienceTo the edito

Early clinical and biological features of severe clinical manifestations of dengue in Vietnamese adults.

International audienceSeveral severe manifestations of dengue were observed in Vietnamese adults. These manifestations were associated with early clinical and biological indicators. This information may be useful for clinicians to better monitor adult dengue patients, particularly in tropical areas where health resources may be limited

Propriétés virologiques et sérologiques de l’infection à virus Chikungunya : bilan de l’épidémie dans les DFA

International audienc

Techniques de routine et approches innovantes pour le diagnostic biologique de la dengue

International audienceDengue fever is a major public health problem in intertropical regions due to the concomitant increases in the frequencies of epidemics and of severe forms of the disease. In the absence of a vaccine, control methods are limited to vector-targeting approaches and early rapid differential diagnosis to improve disease surveillance in populations. Various techniques can be used to diagnose dengue virus infection, depending on the clinical phase during which samples are taken. However, some of these techniques have major disadvantages, ranging from the need to collect venous blood samples from children to serological cross-reactivity between the dengue virus and related viruses, making it difficult to interpret the results. Innovative diagnostic approaches have been developed to overcome these problems and to enlarge the range of available technical tools available: early, rapid detection of the viral NS1 antigen by immunocapture, capillary blood sampling as an alternative to venous blood sampling for diagnosis, the use of IgG avidity to discriminate between primary infection and re-infection and the use of recombinant proteins derived from the viral envelope protein to improve the sensitivity and specificity of immunoenzymatic techniques.La dengue constitue un problème majeur de santé publique dans les régions intertropicales du fait de l’augmentation concomitante des épidémies et des formes sévères de la maladie. Dans l’attente d’un vaccin, les moyens de contrôle restent la lutte anti-vectorielle et la mise en œuvre d’un diagnostic d’infection précoce, rapide et différenciel pour un meilleur suivi des populations. À ce titre, différentes techniques, dépendant de la phase clinique au cours de laquelle le patient est prélevé, peuvent être réalisées pour poser un diagnostic d’infection par le virus de la dengue. Cependant, certaines d’entres elles présentent des inconvénients majeurs allant de la simple réalisation d’un prélèvement veineux chez un enfant à l’existence de réactions sérologiques croisées entre le virus de la dengue et d’autres virus apparentés qui compromettent l’interprétation des résultats. Pour pallier à ces contraintes et élargir par là même l’éventail des outils techniques, de nouvelles approches diagnostiques ont été mises en œuvre : la détection précoce et rapide d’un antigène viral NS1 par immunocapture, le prélèvement de sang capillaire comme alternative au prélèvement veineux pour le diagnostic, l’avidité des IgG pour discriminer une infection primaire d’une réinfection par DENV ou encore l’utilisation de protéines recombinantes issues de la protéine d’enveloppe du virus pour une meilleure sensibilité et spécificité des techniques immuno-enzymatiques

Kinetics of Dengue Non-Structural Protein 1 Antigen and IgM and IgA Antibodies in Capillary Blood Samples from Confirmed Dengue Patients

International audienceLarge-scale epidemiological surveillance of dengue in the field and dengue patient management require simple methods for sample collection, storage, and transportation as well as effective diagnostic tools. We evaluated the kinetics of three biological markers of dengue infection-non-structural protein 1 (NS1) antigen, immunoglobulin M (IgM), and IgA-in sequential capillary blood samples collected from fingertips of confirmed dengue patients. The overall sensitivities and specificities of the tests were 96% and 100%, respectively, for NS1, 58.1% and 100%, respectively, for IgM, and 33% and 100%, respectively, for IgA. During the acute phase of the disease, NS1 was the best marker of dengue infection, with a sensitivity of 98.7%, whereas from day 5, all three markers exhibited relevant levels of sensitivity. This first descriptive study of the kinetics of biological markers of dengue in capillary blood samples confirms the usefulness of this biological compartment for dengue diagnosis and argues for its exploitation in community-level and remote settings