Zika Poses a Challenge to Florida's Solid Waste Departments

With both travel- and non-travel-related cases of the virus found in southern Florida, it is a boots on the ground mentality for both solid waste and public works departments, which are out in neighborhoods looking to destroy possible mosquito-breeding grounds.

While prime mosquito season has passed, the threat of the bloodsucking pest and the spread of Zika virus is still viable in the Sunshine State. In Miami-Dade County, the Mosquito Control Division, which falls under the county’s department of solid waste management, continues to be aggressive in its efforts. The work addresses both residential service requests and referrals from the Florida Department of Health (FDOH) related to suspect and actual Zika cases. 

Less than 24 hours after the announcement of a new Zika zone in Miami-Dade County, where new transmission was verified, mosquito control went to work in the area deploying trucks spraying adulticide, which targets adult mosquitoes when they are most active. Additional truck larvicide treatments happened in the early morning hours beginning around 3 a.m. to eliminate mosquito larvae. The department will continue performing alternating treatments of adulticide and larvicide to reduce the mosquito counts in the area as necessary. Mosquito Control also has deployed BG Sentinel traps in the one-square-mile area to obtain daily mosquito counts to provide data for the most effective treatment plan. The Zika virus is spread through the bite of the Aedes aegypti mosquito, which is often found in stagnant water.

In addition to the truck spray treatments and traps, crews completed more than 200 inspections in the area looking for mosquito breeding and adult mosquito activities around properties. 

Code Enforcement officers from Miami-Dade County and the City of Miami also are making sure that property owners and businesses are eliminating mosquito-breeding conditions. 

“From our experience in treating other areas with locally acquired Zika, we’ve found mosquito breeding in unique spots like elevator shafts, in decorative landscaping where bromeliads are used, at storage yards and at construction sites,” Miami-Dade County Mayor Carlos Gimenez said in a press release. “For example, the jersey barriers used for construction sites are typically filled with water. If that water is not routinely drained, the standing water inside the barriers is the perfect mosquito breeding location,” he said.  

Miami-Dade County is working closely with the Centers for Disease Control and Prevention and the Florida Departments of Health and Agriculture, which are providing guidance and expertise in the areas of medical entomology and vector management in response to Zika. Gimenez has praised their support and recommendations in conjunction with the work of Mosquito Control.

Funding the Zika fight has come mostly from the local level. After stalling for months, Congress recently approved $1.1 billion in federal funding for combating the virus. However, the Centers for Disease Control and Prevention has said the funding may not be readily available and likely will be spent over the coming months.

In the meantime, with the number of non-travel Zika cases in Florida on the rise, Hillsborough County also is among those municipalities taking steps to fight mosquitoes.

The Hillsborough County Solid Waste Division recently hosted several tire amnesty days to rid the county of discarded tires and, at the same time, reduce the mosquito population, by eliminating the potential breeding areas.

“We’ve allowed residents to bring up to 10 tires for free for disposal and we’ve located those throughout the county,” said Kimberly Byer, Hillsborough County solid waste director.

Residents of Hillsborough County, which includes the City of Tampa, took advantage of the tire amnesty collections, dropping off approximately 30 tons of tires, which were disposed of at the county waste-to-energy facility, Byer says.

“We are finding some of the largest hotspots for mosquitoes are around large tire piles. So those are breeding grounds for mosquitoes. So we’ve tried to get as many of those as we can off the streets.”

It can be expensive to recycle tires, says Byer. At the county, it’s nearly $110 per ton for tire recycling and ranges anywhere from $75 to $110 per ton in the area. She adds the county suspects that a lot of the illegal tire dumping is done by commercial businesses, not by residents. The county allows the disposal up to 12 tires per residence, which is included in residential disposal fees.

Byer says the agency continues to do outreach across the county, especially pushing the concept of “drain and cover.”

“Anything as small as a teaspoon can be a breeding ground for mosquitoes,” she says. “So drain and cover any standing water.”

The solid waste division also has done several Fight the Blight events, where illegal dumping of bulky waste is cleaned up by various county departments. Eliminating the waste piles in blighted areas, decreases breeding areas for mosquitoes, Byer says.

Operations this year have made an impact on illegal dumping in Thonotosassa, Lucy Dell and Green Ridge Estates. Combined, the three operations removed more than 32 tons of trash that may otherwise have been discarded illegally.

Among those involved in the event were Hillsborough County Code Enforcement, solid waste and public works. And the Mosquito Control and Aquatic Weed Unit used the cleanup as an opportunity to warn residents of the connection among accumulated debris, standing water and mosquito breeding grounds.

Broward County, home to Fort Lauderdale, also is working to clean up breeding grounds and spray to reduce the risk of Zika transmission to residents. Under the county’s public works department and under supervision of the Highway and Bridge Maintenance Division, the county’s Mosquito Control Section continues to work closely with the Florida Department of Health and Code Enforcement partners in Broward's 31 municipalities to eliminate mosquitoes and their habitats.

Mosquito control is conducting door-to-door backpack spraying, draining standing water where possible, treating standing water with long-lasting larvicide, setting up mosquito traps and sampling adult mosquitoes to gauge effectiveness of those treatments.