Greater LA Vector Control outlines dengue risk, field services and sterile-insect test program

Maritza (Marissa) Olmos, operations manager for the Greater Los Angeles County Vector Control District, told the Bellflower City Council on March 24 that the district provides mosquito surveillance and control services to Bellflower residents as part of a tax-supported program and that residents may request inspections and treatments at no additional charge.

"Our current assessment per single family home is $18.97 annually," Olmos said, adding the district responds to service requests, conducts door-to-door inspections in affected neighborhoods, treats public sources such as underground storm drains and flood-control channels, and operates a swimming-pool inspection program for inoperable pools.

Olmos warned the council that dengue has emerged as a growing threat in the region. "So mosquito borne diseases in Bellflower, we actually have a new growing threat, which is dengue fever," she said, noting recent travel-associated cases and three locally acquired cases within the district. She also described ongoing surveillance for West Nile virus and, occasionally, St. Louis encephalomyelitis.

The district described a three-pillar integrated vector management approach: scientific surveillance (trapping and mosquito identification, dead-bird testing), operational control (inspections, source reduction and treatments) and communications/education (outreach at the farmers market, youth education in schools and requests for a district tab on the city website).

Olmos described a pilot sterile-insect technique (SIT) program that sterilizes male mosquitoes with X-ray irradiation and releases them so matings with wild females produce unviable eggs. She said SIT is nonchemical and aims to reduce mosquito populations without pesticides. "We're in the very, very early stages of this program," she said, adding that the program requires space and equipment to rear insects and that the district has seen encouraging results in test areas.

Councilmembers asked logistical questions about the district's data and resources. Olmos clarified counts mentioned during the presentation: the district tracks roughly 1,347 "residential and public sources" (a category that includes containers, tires and other small sources) and separately monitors 88 ponds and pools. She said last year the district inspected and treated nearly 3,000 sources in Bellflower. She also said the district generally responds within three business days to service requests.

On funding and capacity, district staff said the annual assessment covers services; Olmos said the district's projected budget for fiscal year 2024'25 is roughly $24 million and that the district employs about 100 full-time staff plus roughly 36 seasonal staff during peak season.

Olmos asked the council to consider adding a district tab to the city website to make services easier to access and to continue to encourage residents to call for inspections after rain events. The council discussed coordination for community events; Olmos said the district's outreach bus and youth education programs are available for festivals and school visits.

Council members and staff thanked the district for the briefing and encouraged the city to post district contact information on city platforms. No formal action was taken at the meeting on this presentation.