LA County sees unprecedented cluster of locally acquired dengue fever in people bitten by mosquitoes

LOS ANGELES (KABC) -- For the first time, L.A. County health officials have identified a cluster of dengue fever cases that are not travel-related. Could we be seeing more of this disease in places it's not usually found. Experts say it's important for residents to protect themselves.

We've grown accustomed to these aggressive ankle-biting insects. But the presence of the Aedes mosquito is giving dengue fever a chance to establish a new home.

"The cluster of locally acquired dengue cases is unprecedented because it has never occurred before in L.A. County or in California, " said Dr. Aiman Halai, Director, Vector-Borne Disease Unit, Acute Communicable Disease Control Program with the Los Angeles County Department of Public Health

Health officials identified three cases between September 9th and now. All in the city of Baldwin Park.

"These residents have no history of travel to areas where dengue is commonly transmitted," said Barbara Ferrer, Ph.D., M.P.H., M.Ed., Director, Los Angeles County Department of Public Health.

The dengue virus spreads through mosquito bites not from person-to-person. While the risk remains low, symptoms occur in about one in four people infected

"Fever, rash, muscle aches, bone pain, headache and pain behind the eyes," said Halai.

One in twenty can go on to develop more serious life-threatening complications.Treatment is supportive care. Mosquitoes can carry four different types of dengue.

"A person infected once can get infected again. A second infection with Dengue is a risk factor for severe disease," she said.

"We remind residents that mosquitoes breed in standing water," said Jason Farned, MPA, District Manager of the San Gabriel Valley Mosquito and Vector Control District

Mosquito samples so far remain dengue free. San Gabriel Valley Vector Control staff are going door-to-door in areas where the cases occurred to show residents how to protect themselves and rid their homes of mosquitoes.

"Granting access to your backyards will significantly enhance our ability to reduce mosquito populations and prevent potential infections," said Farned.

Dengue vaccines are not approved for U.S. residents nor travelers. Instead, health officials encourage use of bug repellents containing at least one of these four ingredients: Oil of Lemon Eucalyptus, DEET, Picaridin or IR3535.

"We have a lot of good options now with insect repellent. Everyone should be using it," said Ferrer.

So when will mosquito season end? Vector control officials say it's starting early and ending later. But when the temperatures drop below 50 degrees at night, that's good for us and bad for mosquitoes.