In what could arguably be the greatest immunological breakthrough in decades, French drugmaker Sanofi SA announced that a vaccine against Dengue fever had shown clinical efficacy in recently completed trials. Additional testing is necessary, but the vaccine could be available as early as 2015. Although not a household name, dengue fever is one of the most common mosquito-borne viral illnesses in the world, infecting anywhere from 50-100 million people per year. Also known as “breakbone fever”, more severe cases can result in high temperatures, severe joint and muscle pain, and even death when blood leaks into the body’s tissues from a loss of clotting
cells called platelets. Indeed, over 20,000 deaths occur annually from this “hemorrhagic” form of dengue fever, many more than from the more widely recognized Ebola virus. Dengue fever is spread by the bite of the Aedes aegypti mosquito. The insect thrives in large cities of tropical regions with the result that almost three billion people are at risk of catching the disease, including unsuspecting travelers to Asia, Africa, and parts of South America. Experts estimate that the incidence of dengue fever is probably under-reported, as the infection mimics flu symptoms. Physicians in endemic areas commonly hospitalize tourists who are diagnosed with dengue fever for five to six days to make sure that the hemorrhagic form of the illness does not manifest. HTH urges travelers to countries where dengue fever is endemic to protect themselves against mosquito bites with netting, insecticides and the proper clothing. There is currently no treatment for the disease, making the 70 year quest for an effective vaccine all the more relevant. Photo by Sanofi Pasteur.