Since the mosquitoes that carry the virus travel only a few hundred feet from where they are hatched, the best way to control the spread of disease is to eliminate standing water around the house where mosquito eggs hatch, such as rain barrels, discarded containers, old tires, and birdbaths, he advised. Adequate screening on windows can also help, because mosquitoes look for a place to hide during the day and may be present in dark areas like closets, bathrooms, behind curtains, and under beds. Although mosquito activity is greatest in the early morning and in the late afternoon, they may feed at any time during the day, especially indoors, in shady areas, or during overcast periods, he noted. Dengue fever is an acute viral illness with severe flu-like symptoms often accompanied by a rash on the feet or legs beginning 3 to 4 days after onset of fever. More severe forms are dengue hemorrhagic fever and dengue shock syndrome.
Virologic surveillance is the most important component in an early warning system.