Mosquitoes are abundant in Tennessee, thriving due to the state’s consistently warm and humid climate. The presence of numerous waterways, lakes, and high humidity provides the necessary moisture for these insects to complete their life cycle. Mosquito activity varies throughout the year, with numbers increasing sharply as temperatures rise.
Peak Seasonality and Common Species
Mosquito season in Tennessee generally begins in early spring, typically starting when overnight temperatures consistently remain above 50°F, which often occurs in late March or early April. This initial emergence is fueled by overwintering female mosquitoes seeking a blood meal to develop their first batch of eggs. Spring rainfall contributes significantly by creating numerous temporary pools of standing water, which are perfect breeding sites for the first generations of the year.
Activity escalates rapidly through late spring, but the peak mosquito period is during the hot, humid summer months, generally from June through September. During this time, high temperatures shorten the mosquito life cycle, allowing eggs to mature into biting adults in as little as a week. Two of the most common mosquito genera found in the state are Aedes and Culex.
Aedes species, such as the Asian tiger mosquito (Aedes albopictus), are aggressive daytime biters that breed readily in small containers of water around homes. Culex species are typically more active at dusk and dawn and are known to be vectors for certain diseases.
Health Risks and State Surveillance
Mosquitoes can transmit several diseases monitored by public health agencies. The primary concern in Tennessee is West Nile Virus (WNV), transmitted by infected mosquitoes that have fed on infected birds. The Tennessee Department of Health (TDH) monitors WNV activity closely, tracking human cases and the virus’s presence in collected mosquito samples and deceased birds.
Eastern Equine Encephalitis (EEE) is less common but carries a higher fatality rate in humans. Although EEE cases are rare, the TDH maintains surveillance due to its severity. The risk level for these diseases fluctuates annually based on weather patterns and the size of the mosquito population.
The TDH’s Vector-Borne Diseases program plays a central role in state surveillance efforts by collecting and testing mosquito samples across various counties. This proactive monitoring allows the department to investigate reported cases and issue public health advisories when disease activity increases. Local health departments often collaborate with the state to conduct control measures, such as larviciding standing water to kill mosquito larvae before they mature.
Personal Protection Strategies
Personal bite prevention and source reduction around your property are key strategies. Bite prevention centers on applying EPA-registered insect repellents to exposed skin. Effective active ingredients include DEET, picaridin, or oil of lemon eucalyptus.
When spending time outdoors during peak activity hours, which are typically at dusk and dawn, wearing long sleeves and pants can provide a physical barrier against bites. Additionally, check that all window and door screens are intact and properly sealed to prevent mosquitoes from entering indoor spaces.
Source reduction focuses on eliminating standing water where mosquitoes lay their eggs. This practical step removes the tiny habitats necessary for mosquito reproduction.
Source Reduction Steps
- Drain water from containers such as flowerpots, old tires, and buckets.
- Regularly change the water in bird baths and wading pools.
- Clean out clogged gutters.