Dr Audrey Dubot-Peres from our LOMWRU unit in Laos and IRD (Institut de Recherche pour le Développement, Marseille, France) tells us about her research on viral infections in Laos. Infections such as dengue and Japanese encephalitis are important problems in Laos but confirmed data are lacking, particularly from outside the capital Vientiane. Rapid diagnostic tests that can be kept at tropical room temperature help better diagnosis and treatment, and also inform policy to implement vaccination programmes.