For Immediate Release:

October 30, 2024

Public Health Confirms Two Additional Cases of Locally Acquired Dengue

Healthcare providers urged to be vigilant for dengue

The Los Angeles County Department of Public Health is investigating two additional cases of locally acquired dengue. One additional case has been identified in Baldwin Park, marking the seventh case of dengue confirmed in this area of the County. The increase in the number of locally acquired cases in Baldwin Park indicates continued circulation of dengue in the area due to infected mosquitoes. The second additional case is a resident of Hollywood Hills who had no history of recent travel prior to developing symptoms. It is crucial for people living and working in areas where cases of locally acquired dengue are identified to prioritize mosquito control and prevention measures to reduce the risk of spread.

There have now been eleven confirmed cases of locally acquired dengue this year in Los Angeles County. Public Health urges healthcare providers to consider dengue in patients with acute febrile illness, regardless of travel history, and order appropriate dengue testing if indicated. Providers should also routinely discuss mosquito bite prevention with patients, particularly those planning travel to areas where dengue is known to occur. Residents experiencing symptoms should see their healthcare provider and mention their exposure to mosquitoes.  Dengue symptoms mimic other viruses and include high fever, severe headache, pain behind the eyes, joint and muscle pain, rash and possibly, mild bleeding.

Dengue spreads through the bite of infected Aedes mosquitoes. Sustained spread of dengue in a neighborhood occurs when infected mosquitoes bite and spread dengue to people, who are then bitten by other mosquitoes. Those mosquitoes become infected and continue the cycle. As new cases continue to be identified, there is increasing concern about the potential for spread of dengue to other areas of Los Angeles County especially as people travel throughout the County.

“These two additional cases raise concerns about the potential for continued local spread of dengue in our community. Healthcare providers play a critical role in promptly identifying and managing patients infected with dengue,” said Muntu Davis, MD, MPH, Los Angeles County Health Officer. “Providers should consider dengue in any patient with fever and signs and symptoms of dengue including headache, eye pain, muscle, bone or joint pain, nausea and vomiting and order testing for dengue regardless of travel history.”

Residents and businesses are strongly encouraged to take advantage of free vector control services including inspection and abatement of mosquito breeding sites at their homes. This is essential to helping identify and reduce the risk of further local spread of dengue.

Some additional important steps residents can take include:

• Wearing Mosquito Repellent: Mosquito repellents can prevent mosquito bites. EPA-registered repellents containing DEET, picaridin, IR3535, 2-undecanone, and oil of lemon eucalyptus are the longest lasting and most effective. They are available as sprays, wipes, and lotions. Consider wearing long-sleeved clothes and pants when outside.
• Keeping mosquitoes out of homes: Make sure that doors and windows have tight-fitting screens to keep out mosquitoes. Repair or replace screens with tears or holes.
• Preventing mosquito breeding:
  • Eliminate standing water where mosquitoes can lay eggs.
  • Clear standing water in flowerpots, saucers, birdbaths and other outdoor containers. Empty items that hold water inside and outside your home once a week. Mosquito eggs only need a thimbleful of water to hatch.
  • Cover water storage containers such as buckets and rain barrels. For containers with no lid, use wire mesh with holes smaller than an adult mosquito.
  • Clean and maintain swimming pools, spas and drain water from pool covers.
  • Throw away old items in your patio or yard that can hold water, e.g., old car tires and children’s toys. Call 2-1-1 or your local vector control agency to report persistent problems to your mosquito control district.

Public Health continues to work closely with vector control districts on enhanced surveillance and active engagement with the community to help with mosquito control. Outreach teams are visiting residents in the area where cases are identified to provide information on dengue, offer dengue testing, and encourage residents to take protective measures against mosquitoes. The San Gabriel Valley Vector Control District and the Greater Los Angeles Vector Control District have increased mosquito trapping for identification and testing and abatement operations to reduce the risk of additional spread in the affected areas.

Public Health’s first confirmed case of locally acquired dengue was reported September 9, 2024. Panorama City and El Monte have each seen one and two cases respectively suggesting the virus has infected the local mosquito population in those cities. So far, none of these people have developed severe disease. For the most up to date case counts of locally acquired dengue in LA County visit: publichealth.lacounty.gov/acd/VectorDengue.htm

• Cases of locally acquired dengue were previously confirmed by Long Beach and Pasadena in fall 2023.

About Dengue

Dengue is a viral infection that spreads from mosquitoes to people. It is common in tropical and subtropical regions, like the Caribbean (including Puerto Rico), Central and South America, Southeast Asia, and the Pacific islands. In the United States, the types of mosquitoes that spread dengue are found in many areas, which means local spread of dengue can happen. However, dengue is not commonly spread by mosquitoes in LA County. Most cases in LA County have been linked to travel to areas where dengue is more common.

About one in four people infected have symptoms of the infection, which can be mild or severe. Symptoms of dengue typically last two to seven days. Most will recover after about a week. About one in twenty people with symptoms can develop severe disease with severe bleeding, shock, trouble breathing, and organ damage, which can be life threatening.

The most common symptoms of dengue are fever and any of the following:

• Aches and pains (headache, eye pain, muscle ache or joint pain)

• Nausea or vomiting

• Rash

Warning signs that severe disease may develop include any of the following:

• Severe, constant stomach pain or pain when touching the stomach
• Vomiting a lot (3 times in 1 hour or 4 times in 6 hours)
• Bleeding from the gums, nose, or vagina, or blood in urine
• Changes in how a person acts (like being very irritable or sleepy)

There are no antiviral medicines approved to treat dengue. Treatment is supportive and may require carefully managing fluid levels. There is a vaccine for dengue, but it is NOT approved for use in U.S. travelers who are visiting but not living in an area where dengue is common.

For more information, visit: publichealth.lacounty.gov/acd/VectorDengue.htm

For questions or to find a nearby clinic or doctor, call the Public Health InfoLine at 1-833-540-0473, open every day from 8 a.m. to 8 p.m.