Pasadena confirms rare case of locally-acquired dengue

Amy Powell Image
Saturday, October 21, 2023
Pasadena reports rare case of locally acquired dengue virus
The Pasadena Public Health Department confirmed a case of dengue in a Pasadena resident who did not recently travel outside the United States.

PASADENA, Calif. (KABC) -- An illness that is usually found on the other side of the world has been discovered in Southern California, and it did not involve travel.

The Pasadena Public Health Department on Friday confirmed a case of dengue in a Pasadena resident. They said it is the first confirmed case of the illness in California not associated with travel and is "instead an extremely rare case of local transmission in the continental United States."

The public health department affirms that the risk of exposure to dengue, which is spread through mosquitoes, for residents is very low, but asks everyone to take standard precautions.

The San Gabriel Valley Mosquito and Vector Control District says it has deployed traps to assess the mosquito population. Mosquitos only need a small amount of stagnant water to breed, which can quickly result in mosquito breeding sites around your home and yard.

A person can be infected with the dengue virus from an infected Aedes mosquito.

"Although Pasadena is home to the Aedes mosquito, the disease is not established (endemic) in California. In the U.S., dengue cases are typically seen in travelers who have visited countries where dengue is found," said the PPHD in a press release.

READ | After wet winter, LA County health officials preparing for 'heavy' mosquito season

Officials conducted an emergency-response training exercise in Whittier to encourage residents to "tip and toss" stagnant water to prevent invasive Aedes mosquitoes.


The Pasadena Public Health Department urges the community to follow standard precautions to reduce mosquito populations and the risk of mosquito-borne diseases.

Eliminate standing water in clogged rain gutters, rain barrels, discarded tires, buckets, watering troughs, or anything that holds water for more than a week.

Ensure that swimming pools, spas, and ponds are properly maintained.

Change the water in pet dishes, birdbaths, and other small containers weekly.

Report neglected swimming pools in your neighborhood to your vector control district.

To prevent mosquito bites, PPHD recommends:

Wear insect repellent containing CDC and EPA approved active ingredients: DEET, picaridin, IR3535, or oil of lemon eucalyptus.

Wear loosely fitted, light-colored, long-sleeved shirts and long pants.


Symptoms may be mild or severe and include fever, nausea, vomiting, rash, and body aches. Symptoms typically last two to seven days and although severe and even life-threatening illness can occur, most people recover after about a week. There are no specific medicines or vaccines to prevent this disease. Treatment is supportive and may include rest, fluids, and monitoring for early signs.

For additional information, visit, California Department of Public Health, and the Centers for Disease Control and Prevention websites.