The disease is spread through mosquito bites and causes symptoms including fever, headache, nausea, vomiting, rash, and pain in the eyes, joints and muscles. Following a mosquito bite, symptoms can take up to two weeks to develop and tend to last less than a week. However, in severe cases symptoms can include haemorrhage, shock, organ failure and death. The key measures travellers can take to avoid dengue revolve around preventing mosquito bites by using insect repellant and covering skin.
Dengue is also causing concern in Singapore where, according to the National Environment Agency, the ‘persistently high Aedes aegypti mosquito population increases the risk of transmission of the dengue virus’ and active clusters have more than doubled over the past five weeks.
In Vietnam, meanwhile, this year dengue fever cases have tripled in the capital, Hanoi, compared with the same period last year. This is largely to do with the weather providing ideal conditions for mosquitos to proliferate.