All articles tagged with #vector control
Los Angeles County has confirmed its first West Nile virus–related death of 2026 amid a rise in local infections (15 cases so far this year, above the five-year average). Statewide activity is also at a five-year high, prompting officials to urge residents to use insect repellent, remove standing water, and ensure window screens are intact to prevent mosquito bites, especially for older adults and the immunocompromised.
New York City is seeing a surge in West Nile virus in mosquitoes, with 612 West Nile virus–positive mosquito pools detected by July 25—nearly double last year’s 326—prompting expanded mosquito surveillance and four targeted control operations. No human cases have been reported yet. Health officials remind residents to use EPA‑registered repellents, limit outdoor activity at dawn and dusk, repair screens, and remove standing water as part of the ongoing June–October transmission season.
Orange County is on track for the most West Nile virus activity in its history, with the Orange County Mosquito and Vector Control District reporting 102 West Nile–positive mosquito pools so far this year (186 in all of 2025) and the heaviest activity in Anaheim, Buena Park and Fullerton; no human infections have been reported yet this year, though warmer weather is accelerating mosquito breeding. The district is spraying and releasing sterilized male mosquitoes while urging residents to remove standing water, use repellents, keep screens intact, and report dead birds to help track the spread.
In Mukalla, health workers comb slum areas for stagnant water to curb a dengue outbreak that has strained Yemen’s already fragile health system, finding both dengue and malaria larvae and facing limited funding, delayed care, and uneven public cooperation as residents store water and hinder control efforts.
Australian field trials releasing Wolbachia-infected male mosquitoes dramatically reduced Aedes aegypti populations and provided proof-of-principle that large-scale male releases can work with minimal ecological impact, offering important lessons for Google's planned 32 million sterile/incompatible-male releases in California and Florida—emphasizing community engagement, regulatory approvals, and robust sex-separation technology.
Southern California is in peak mosquito season as West Nile–infected mosquitoes rise and invasive Aedes aegypti populations are targeted with Sterilized Insect Technique (SIT) releases. Authorities emphasize eliminating standing water to curb breeding, note SIT programs in the San Gabriel Valley and other areas as promising but still experimental, and report two human West Nile cases so far with no vaccine available.
San Gabriel Valley Mosquito and Vector Control District is releasing about 480,000 sterile male Aedes aegypti mosquitoes over 16 weeks in a 25-acre Bassett area to prevent wild females from producing offspring, using Wolbachia bacteria; since these are males, they don’t bite, and the program aims to reduce mosquito bites and dengue risk as peak season arrives.
West Nile‑carrying mosquitoes are spreading rapidly through Los Angeles and Orange counties, with LA County reporting 27 positive samples and Orange County detecting West Nile in 38 mosquito pools. Nationally, human cases are at a mid-year high not seen since 2004, though California has only one reported human case so far this year. There is no specific treatment; most infections are mild or asymptomatic, but about 1% can progress to neuroinvasive disease, which can be severe and sometimes fatal. Prevention focuses on reducing breeding sites and avoiding bites: use EPA‑recommended repellents (DEET, IR3535, oil of lemon eucalyptus, or Picaridin), wear long sleeves/pants at dawn/dusk, remove standing water, maintain screens, and report dead birds or large breeding sites to local vector control.
The United States plans to combat a flesh-eating screwworm outbreak in the southern states using flies and detection dogs, marking its first appearance in the country since 1966 (as of June 6, 2026).
In Washington, DC, Michelle Mingrone rallied 1,800 homes into the Itty Bitty Mosquito Population Committee to tackle mosquitoes without spraying, using standing-water elimination, larvicides in larger ponds, lure-and-trap devices, plant choices, and community outreach. The effort, supported by 220 block captains, reflects broader climate-driven mosquito spread and gaps in municipal control, while experts caution that eradicating all mosquitoes isn’t feasible, though reducing human-biting species is possible with targeted tools.
Berkeley health officials confirmed the city's first human leptospirosis cases in more than a decade, including a May death of a man living in a severely rat-infested RV near the Harrison Street encampment; his companion also fell ill but recovered after a lengthy hospitalization. The couple trapped and bred wild rats inside the RV, delayed seeking care, and nearly 200 rats were removed before the vehicle was destroyed. Two dogs also tested positive. The city had previously set a buffer zone for rodent eradication and is now focusing on enhanced sanitation, vector suppression, and outreach, noting that the general public risk remains very low while those living near rats face higher exposure.
Google seeks EPA approval to release up to 64 million Wolbachia-infected sterile male Aedes aegypti in California and Florida over two years to reduce disease-carrying mosquito populations. The effort would involve advanced sex-sorting tech, monitoring tools, and strategic releases, building on earlier trials that showed substantial drops in female mosquitoes, though cost and expansion hurdles remain as California faces ongoing dengue risk.
Google is seeking EPA approval to release 32 million lab-bred sterile male mosquitoes in Florida and California over two years as part of its Debug initiative, using a Wolbachia bacterial strain to ensure eggs don’t hatch when these males mate with females, thereby reducing the overall mosquito population and the spread of diseases; the plan, which entails 16 million releases in year one and 16 million in year two, is awaiting regulatory approval and details on host locations, reflecting a long history of sterile-insect techniques.
With Cayman’s rainy season underway, the Mosquito Research and Control Unit is intensifying efforts, conducting island-wide daytime aerial larviciding to kill mosquito larvae before they become biting adults, alongside surveillance and biological controls. Scientists identify 36 species on the islands, notably Aedes aegypti, which spreads dengue, Zika and chikungunya. Mosquito bites are more likely in people with higher body heat and carbon dioxide output, skin bacteria, or sweat chemistry, and ankles, wrists, and neck are common bite sites. Residents are urged to remove standing water and support integrated pest management, including Gambusia fish, to curb emergences.
Costa Rica confirmed its first chikungunya case in nine years—a 24-year-old man from Esparza, Puntarenas—after lab confirmation, prompting fumigation across Esparza and planned follow-up spraying to curb transmission. Authorities emphasize vector control, urge residents to remove standing water, use repellent, and seek medical care if symptoms appear, as surveillance continues; the virus last appeared in the country in 2017, with ongoing dengue activity in the region.