People suffering from dengue fever are at two times higher risk of stroke, especially during the first two months following infection, a study warns. Dengue is a mosquito-borne viral infection that infects at least 100 million people every year around the world, with about four billion people at risk of the illness, which includes dengue hemorrhagic fever that can lead to spontaneous bleeding, organ failure and death.

"Clinicians in dengue-endemic areas should be aware of this association, especially for patients with dengue who have neurologic deficits or for patients with stroke who have unexplained fever," said Chia-Hung Kao, China Medical University Hospital in Taiwan. The study, published in the Canadian Medical Association Journal (CMAJ), looked at data on 13,787 patients, most between 31 and 60 years of age, with newly diagnosed dengue between 2000 and 2012.