Worldwide, there are an estimated 50–100 million cases of dengue virus infection each year. Far North Queensland has experienced dengue epidemics, with deaths reported in outbreaks in 2004 and 2008–2009. 1

A 38-year-old man presented one day after returning from Colombo, Sri Lanka. He was a Sri Lankan-born Australian resident with no significant past medical history. He was admitted 10 days after the onset of a biphasic febrile illness: fever, chills, and generalised myalgia for 4 days, resolution of symptoms, then recurrence of symptoms on Day 7. On the day of admission, he developed diarrhoea and bloodstained vomiting. Dengue non-structural protein 1 (NS1) antigen was detected, and results of tests for dengue immunoglobulin (Ig) M and dengue IgG antibody were positive, suggesting secondary dengue virus infection.