Honeybees were dropping like flies in South Carolina last week.

As applicators sprayed insecticide to combat Zika virus-carrying mosquitoes, millions of honeybees were exposed to the toxic chemicals and died, leaving many asking how this could have happened.

While this mass killing of bees occurred in another state, it’s a situation that officials try to prevent all over the country.

Stacey Harris, environmental health specialist with the Beaufort County Public Health Department, said Beaufort County officials work to avoid these unintended consequences by alerting the public to any spraying, as well as spraying at night when bees are in their hives. Hive caretakers are given the opportunity to cover their hives as a precaution, and officials also avoid spraying around ponds and aquaculture areas.

Harris said the chemicals used work best at night because the heat of the sun lessens their effectiveness, as the chemical becomes suspended in the air like fog instead of settling.

“Any spraying with the products we use must be done at night to gain maximum effectiveness, and therefore, pose little risk to the bee population. Our product would have to come into direct contact with the bee,” he said. “Additionally, any chemical residual left behind from spraying becomes inert within 24 hours.”

The state has also worked to keep open lines of communication between beekeepers and pesticide sprayers, according to Gene Fox, area consumer horticulture agent for the North Carolina Cooperative Extension. Beekeepers can sign up for a registry, alerting pesticide applicators of the locations of beehives and alerting beekeepers to upcoming sprays.

Besides the local honey producers, honeybees play a large role as far as pollinating crops and gardens, according to Fox. Growers rely on honeybees to keep crops thriving and reproducing.

“Pollinators carry pollen from one flower to another, and in the process, fertilize the flowers to produce fruits, vegetables and nuts that we consume every day,” Fox said. “In North Carolina, we need pollinators for crops such as apples, blueberries, cucumbers, squash, pumpkins, watermelons, strawberries, peaches … and many others.”

The North Carolina State Beekeepers Association is the largest beekeeping organization in the country and has more than 2,000 members. The Beaufort County Beekeepers Association lists about 40 members.

Harris said environmental health officials have not had to spray a lot in the past few years and haven’t sprayed this summer because the high temperatures kept mosquitoes at bay.

He said the latest rain from Tropical Storm Hermine could cause a mosquito population spike, but the health department is constantly monitoring conditions with weekly light traps and testing.

The Zika virus, which can cause microcephaly, or undeveloped heads, in infants, is spread through Asian tiger mosquitoes that breed and lay eggs in standing water, especially in residential areas.

Although the health department remains vigilant, Harris said there is still little cause for concern about the Zika virus in Beaufort County, despite one confirmed case in Nash County.

He said the department works with Extension agents to make sure both residents and other species are protected when spraying is necessary. By doing that, Beaufort County officials hope to avoid the South Carolina disaster.

For more information, call the Extension office at 252-946-0111. To register a beehive location, visit www.ncagr.gov/plantindustry/plant/apiary/index.htm or https://nc.drfitwatch.org.