Hillsborough extended its dengue emergency to Oct. 29 with 346 locally acquired cases. Where planes sprayed Tampa last week and how to get spray alerts.
Hillsborough County has extended its dengue state of local emergency for a fifth week, to Thursday, Oct. 29. The state’s count of locally acquired dengue cases in the county stands at 346.
County Administrator Bonnie Wise signed the new executive order Oct. 22. The county’s announcement said mosquito surveillance in many neighborhoods is still showing dengue virus in the mosquito population. It asked residents to look for and get rid of standing water after recent heavy rains.
Updated Oct. 25: the county extended the emergency Oct. 22 to Thursday, Oct. 29, and last week’s airplane spraying of Tampa neighborhoods has ended. The state’s week 42 count had not been published by Sunday evening.
Updated Oct. 22: the emergency was extended Oct. 15 to Oct. 22, the state count for Hillsborough had reached 346, and airplanes were treating Tampa neighborhoods through Friday night. Earlier versions of this story reported the Oct. 8 extension and a count of 259.
The outbreak is the largest in Florida this year by a wide margin. The Florida Department of Health’s latest weekly surveillance report counts 346 locally acquired dengue cases in Hillsborough County through Oct. 17. That is 346 of the 425 cases caught inside Florida so far in 2026.
Airplane spraying, Oct. 20-23
Contractors for Hillsborough County Mosquito Management Services sprayed Dibrom insecticide from airplanes at 300 feet. The flights ran between sunset and midnight, Tuesday through Friday, Oct. 20-23. They covered about 225,000 acres from Carrollwood to FishHawk Ranch, the county’s Oct. 20 notice said.
The areas in and around Tampa on the county’s list are:
- South Tampa
- Downtown Tampa
- Davis Islands and Harbour Island
- Seminole Heights
- East Tampa
- the USF area
- Town ‘N Country and Carrollwood
Low-flying helicopters also dropped a larvicide called Bti on standing water by day, Oct. 19-23. In the city, that covered East Tampa and East Lake between North 22nd Street and the Tampa Bypass Canal, from the Hillsborough River south to I-4. The county’s Oct. 19 notice warned of “significant and readily noticeable helicopter noise.”
How fast the count has grown
Locally acquired means the person caught dengue here, not while traveling. The state’s count for Hillsborough rose by 53 cases in the week to Sept. 26, from 170 to 223. It rose by another 36 in the week to Oct. 3, to 259. Then it rose by 51 in the week to Oct. 10, to 310, and by 36 in the week to Oct. 17, to 346.
The county said Oct. 22 that cooler, drier weather generally slows mosquitoes but will not stop them. Sprinklers, leaking faucets, clogged gutters and containers still give them places to breed.
The state’s weekly reports give these running totals for Hillsborough:
| Report covering the week ending | Hillsborough cases | Source |
|---|---|---|
| Aug. 29 | 59 | Week 34 report |
| Sept. 5 | 95 | Week 35 report |
| Sept. 12 | 134 | Week 36 report |
| Sept. 19 | 170 | Week 37 report |
| Sept. 26 | 223 | Week 38 report |
| Oct. 3 | 259 | Week 39 report |
| Oct. 10 | 310 | Week 40 report |
| Oct. 17 | 346 | Week 41 report |
The week 41 report also says:
- 322 of the Hillsborough cases were typed as DENV-2. The type of the other 24 is unknown.
- 10 of the Hillsborough cases had onset in October, 177 in September.
- Pinellas County has 51 locally acquired cases and Miami-Dade County has nine.
- Statewide, 57 new locally acquired cases were reported in the week of Oct. 11-17.
- As of Oct. 17, Hillsborough is one of eight counties under a mosquito-borne illness alert, with Pinellas and Pasco. Ten others are under an advisory.
City staff go door to door
City of Tampa staff and the Florida Department of Health went door to door from 8 a.m. Friday, Oct. 9. They talked to residents about lowering the risk of infection, the symptoms of dengue and what to do if you have them. The city’s announcement said the teams were visiting neighborhoods where the state has reported cases, including:
- Southeast Seminole Heights
- North Hyde Park
- West Tampa
- Forest Hills
- Sulphur Springs
The city’s Neighborhood Enhancement Department, better known as Code Enforcement, is also going after illegally dumped tires, which hold rainwater. The city said crews removed 23 tons of tires in the past three months. The department is monitoring 85 locations, and two have been cited.
What the emergency does
The county first declared the emergency on Thursday, Sept. 24. Under state law it lasts only seven days unless it is extended, which is why it needs renewing each week.
The county said the declaration lets the county administrator and emergency managers act quickly. It also opens a path to federal reimbursement of some costs. Mosquito Management Services is increasing treatments from the air and on the ground. It is working with the Florida Department of Health in Hillsborough County.
Where helicopters have sprayed in Tampa
The county has flown repeated nights of adult-mosquito spraying over Tampa neighborhoods. Each run used Dibrom insecticide from a helicopter at 150 feet, from 7:30 p.m. to 6 a.m.
- Tuesday, Sept. 29: a large area of central Tampa. It ran from Busch Boulevard south to State Road 60, and from the Veterans Expressway east to the Hillsborough River, I-275, North 21st Street and the Tampa Bypass Canal. Tampa International Airport was excluded. Read the Sept. 29 notice.
- Wednesday, Sept. 30: Palmetto Beach, Channelside and Water Street, plus Palm River just east of the city. Read the Sept. 30 notice.
- Thursday, Oct. 1: South Tampa from I-275 to Gandy Boulevard, plus Davis Islands and Harbor Island. Oct. 2 and 3 were set as backup dates. Read the Oct. 1 notice.
- Monday, Oct. 5: South Tampa, Davis Islands and Palm River. Read the Oct. 5 notice.
- Wednesday, Oct. 7: the University area and Temple Terrace, from Fowler Avenue south to Sligh Avenue and the Hillsborough River, between Armenia Avenue and U.S. 301. Manatee County Mosquito Control District flew with the county that night. Read the Oct. 7 notice.
The Friday, Oct. 9 flight treated Apollo Beach, Ruskin and Wimauma in south Hillsborough, not the city. Read the Oct. 9 notice.
Low daytime helicopter flights are a different job. The county explained on Oct. 2 that daytime crews drop a larvicide called BTI on breeding water. They sometimes fly a few feet off the ground near the coast, so they can be loud.
What it means for you
The county asked people to follow its “3 Ds”:
- Dress in light-colored, long-sleeved clothing and closed-toe shoes.
- Defend with a repellent containing DEET, picaridin, IR3535 or oil of lemon eucalyptus.
- Dump or cover standing water around your home.
To know when spraying is coming to your street:
- Sign up for the county’s spray alerts for your neighborhood.
- Check the county’s mosquito operations page, which shows where treatments are happening.
- Call Hillsborough County Mosquito Management Services at 813-635-5400.
Old tires hold water and breed mosquitoes. The county’s free disposal of up to 12 tires a year is for unincorporated residents only. The county said Tampa residents should check with the city for tire disposal.
The emergency order is due to expire Thursday, Oct. 29, unless the county extends it again. We will update this story when it does. For more on who runs what locally, see our guide to Tampa, Hillsborough County and the neighbors.
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