The biggest hope for prevention lies with a vaccine, Margolis said.
"There is a lot of effort on dengue vaccines going on, but it's going to be another three or four years before a vaccine is approved," he said. There are vaccines currently in clinical trials, he added.
Trying to control the mosquitoes to curb infections has not proven to be all that effective, he said. People who have air conditioning or screened windows may be at lower risk, since a closed house keeps the flying insects at bay.
Infectious disease expert Dr. Marc Siegel, an associate professor of medicine at New York University in New York City, agreed with the experts' warnings. "I wouldn't be surprised to see more cases," he said.
The problem is that the mosquitoes in Key West are now carrying the disease, which makes it more likely that there will be more outbreaks, Siegel said.
For more information on dengue, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Carina Blackmore, Ph.D., Florida Department of Health, Tallahassee; Hal Margolis, M.D., chief of the dengue branch, U.S. Centers for Disease Control and Prevention; Marc Siegel, M.D., associate professor, medicine, New York University, New York City; January 2012, Emerging Infectious Diseases
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