2025 Vector-Borne Disease Season: What’s Emerging Across the U.S.

By: Richard Rich

As mosquito season stretches later into the fall of 2025, public-health agencies are reporting an unusually active year for several vector-borne diseases—those spread by mosquitoes and ticks. R&R Lotion is taking a closer look at what’s happening nationwide and how to protect yourself, your team, and your community.

West Nile Virus: Still the Leading Mosquito Threat

West Nile Virus (WNV) continues to dominate mosquito surveillance in the U.S. This year’s numbers are tracking higher than normal, with the CDC confirming more than 700 human cases across 39 states—nearly two-thirds of them severe, neuroinvasive infections.

Local health departments from Texas to Pennsylvania are detecting record mosquito-trap positives:

Hays County, TX recently confirmed WNV in mosquito pools for the first time this season.
Luzerne County, PA found more than double the number of positive traps compared with 2023.

The virus thrives in the warm, stagnant water left after summer rains, and the warm early-fall weather many regions are seeing means mosquitoes—and risk—linger well past Labor Day.

Chikungunya Makes a Rare U.S. Appearance

In October 2025, New York State confirmed its first locally acquired chikungunya case in six years. The infected resident had not traveled abroad, signaling that the Aedes mosquitoes capable of transmitting the virus are now established enough to sustain limited domestic spread.

While the CDC stresses that risk remains low, the case highlights a broader reality: climate shifts and global travel are expanding the reach of mosquito species once confined to the tropics.

Other Vector-Borne Diseases to Watch

Beyond West Nile and chikungunya, surveillance networks have picked up activity for several other mosquito- and tick-borne infections:

Dengue – Dozens of U.S. travel-associated cases and isolated local events in Florida and Texas.
Eastern Equine Encephalitis (EEE) – Detected in horses in Michigan, signaling regional virus circulation.
Jamestown Canyon and St. Louis Encephalitis – Positive mosquito pools in multiple Midwestern states.
Tick-borne illnesses such as Lyme disease and Rocky Mountain Spotted Fever remain widespread through autumn, especially after this year’s wet spring created lush tick habitat.

Together, these detections paint a picture of a longer, more complex vector season—one that challenges both individuals and organizations to rethink year-round protection.

Prevention: The Human Factor Matters

Because there are no vaccines or antiviral treatments for most of these viruses, prevention still comes down to personal and workplace habits:

Remove standing water around homes, jobsites, and storage areas.
Wear long sleeves and light-colored clothing outdoors at dawn and dusk.
Use a repellent with a proven active ingredient—and apply it properly.

The R&R Lotion Response: I.C. Insect Repellent Lotion and Spray

R&R Lotion’s I.C. Insect Repellent line was developed to meet exactly this challenge. Formulated with IR3535®, a gentle yet highly effective repellent molecule recognized by the EPA and World Health Organization, our lotion and spray provide durable protection against mosquitoes, ticks, and biting flies—without the odor or harshness of traditional DEET products.

Why IR3535 Matters

Scientifically proven efficacy against the vectors that spread West Nile, chikungunya, dengue, and tick-borne diseases.
Skin-friendly formulation developed to pair with R&R Lotion’s history of industrial-grade, skin-safe products.
Compliance-ready packaging for workplace safety programs that value both protection and comfort.

Whether you’re safeguarding outdoor crews, travelers, or families, I.C. Insect Repellent Lotion and Spray deliver a reliable layer of defense in an increasingly unpredictable vector season.

Stay Protected, Stay Productive

Vector-borne disease risks will continue to evolve as climates and ecosystems change. This year’s rise in mosquito and tick activity reinforces one simple message: prevention is the best protection.

R&R Lotion will continue to share science-based updates and provide products that help keep your people safe—because healthy skin and a healthy workforce go hand in hand.