Mosquito Bite Waiting To Happen – Part 2 of 3
Ultimately, 93 patients in the Key West tract alone were diagnosed with the disease during the outbreak, which seemingly ended in 2010, with no new cases reported in 2011. But the need of later cases does not give experts much comfort. The reason: 75 percent of infected patients show no symptoms, and the large “house mosquito” population in the region remains a disease-transmitting disaster waiting to happen.
To attempt and get a handle on just how serious that risk might be, the CDC team looked at blood samples from 16 of Florida’s 67 counties, collected from dengue patients by the Florida Department of Health. Rigorous genetic testing revealed what researchers feared: the cataloguing of a local Key West strain among dengue patients who had not recently traveled outside the United States.
The set was able to trace the new Key West strain back to its original imported source: a Central American viral strain initially brought into Florida by patients infected in that region. But they stressed that as the specific mosquito population acquired the virus from this first round of patients, it developed into a distinct strain of its own. In turn, the new strain was passed on to local residents who had not recently visited Central America.
The upshot: In some cases the dengue fever “smoking gun” was the townsman Florida mosquito population, rather than mosquitoes from other regions. “But the Key West virus exceed did not resemble those found elsewhere in Florida,” said Carina Blackmore, chief of the Florida Department of Health’s bureau of environmental public health medicine in Tallahassee. This implies that while patients in the Key West department had indeed contracted dengue from local mosquito carriers, patients in other parts of the state got sick through more typical means: travel abroad.