Sir, in a patient with the complaint of a strange or bad taste, the cause is typically difficult to diagnose, and treatment challenging. As always, the history is of paramount importance to diagnosis, and must always include exploration of lifestyle and environmental factors. A 70-year-old British woman complained of a strange persistent metallic taste since her summer holiday in Thailand 2012, although it was slowly spontaneously resolving. The medical history was non-contributory, except that she had contracted dengue haemorrhagic fever (DHF) in 2012 and been hospitalised; further questioning revealed this was just before the onset of the oral complaint. Extraoral and oral examinations revealed nothing of significance. The taste perversion was attributed to the dengue and treated with reassurance and B complex vitamins. Taste abnormalities in dengue, though unmentioned in most publications on dengue or oral disease, were first reported after the Second World War1 with sparse reports thereafter.2,3 Dengue fever has re-emerged since 1950 with an ever expanding geographic distribution of both the viruses (dengue virus [DENV] serotypes 1-4) and the mosquito vectors (Aedes aegypti and Aedes albopictus), and the emergence of DHF in new geographic regions. It is currently the most important tropical infectious disease after malaria. About 40% of the world's population live in areas at risk for dengue transmission, such as endemic areas which include many popular tourist destinations in at least 100 countries in Asia, the Pacific, the Americas, Africa, and the Caribbean – though the mosquitoes can be found worldwide. Most cases seen in the developed world have been acquired elsewhere, by travellers or immigrants. The principal features of dengue fever are fever, headache, retro-ocular pain, joint pain, muscle and bone pain, rashes, and mild bleeding (eg from nose or gingivae) and easy bruising. DHF is a more severe form of infection, which can be fatal if unrecognised and not properly treated. There is, however, no specific treatment, only symptomatic care and attention to fluids and haemostasis. The most effective protective measures for dengue are those that avoid mosquito bites.4 The case illustrates the importance to dental professionals of taking a full travel and lifestyle history, and using the literature; and, to the public, due consideration of both the opportunities and potential challenges of global travel.