By Tad Helmstetler

Rowan County Health Department

With the 2016 Summer Olympics soon to start in Brazil, renewed fears of Zika virus transmission to spectators and athletes has led to the formation of a rapid response team to respond to active Zika cases. The chances of North Carolina having local transmission of Zika has been rated as low, due to the low numbers of Aedes aegypti mosquitos in the state. The chances of a widespread outbreak in North Carolina are rated as very low.

Since Zika infection in North Carolina is likely going to be acquired elsewhere and brought back to the state, the North Carolina Department of Health and Human Services has assembled a team of mosquito professionals from industry, academia and public health to respond to confirmed or suspected Zika cases in the state. This team of professionals is called the N.C. Public Health Entomology Response Team (NC PHERT) and can be activated by the local health director to stop active Zika cases from leading to local transmission through mosquitos.

The initial stage of an investigation will involve collecting adult mosquitos and immature mosquitos from a radius of 150 meters from the residence of the Zika case. This allows rapid identification of the species of mosquitos which inhabit that area. By determining species, we can determine the types of control measures required to reduce or eliminate the mosquito population before local virus transmission can occur.

After the mosquito populations have been identified, appropriate control measures, such as “tip and toss,” larviciding dunks and barrier spraying for adults can be initiated. Since Aedes mosquitos are container breeders, “tip and toss,” and larvicide treatment of larger water containers would be most helpful in mosquito population reduction. If adulticiding measures are required, the applicator must be licensed in the appropriate category by the Department of Agriculture and Consumer Services.

Local public health personnel are utilized by the PHERT for their familiarity with the location and their ability to secure permission from neighbors to access adjoining properties. Surveillance activities can be established using a variety of mosquito traps that work in various ways to monitor mosquito populations over time to confirm that habitat reduction has effectively reduced or eliminated the adult mosquito population in the target area. Long-term population control is the goal of any effective mosquito control program.

Rapid response to confirmed or suspected Zika cases is key to preventing local transmission to others or widespread transmission to the wider community. Trained professionals working together can stop the Zika virus from becoming established in this state.

For more information or for Zika/mosquito handouts, including a homeowners checklist to prevent mosquitos, visit Rowan County Environmental Health at 402 N. Main St. or call 704-216-8525.

Helmstetler is environmental health supervisor with the Rowan County Health Department.