For the sixth year in a row, Los Angeles has been ranked the top U.S. city for mosquito activity, according to the 2026 Mosquito Cities List released by Orkin.

Once concentrated in the Southeast—where cities like Atlanta previously dominated—mosquito activity has now spread across the country. Today, cities in every region are experiencing increased mosquito pressure, signaling a shift in environmental and public health dynamics.

Mosquitoes are not just a seasonal nuisance. They are widely considered the deadliest animal in the world, responsible for more than 600,000 malaria-related deaths annually, according to the Centers for Disease Control and Prevention. In the United States, they can transmit serious illnesses including West Nile virus, Eastern Equine Encephalitis, Zika virus, and increasingly, dengue fever.

Recent trends show notable increases in mosquito activity in Midwestern cities, while new regions—including places not traditionally associated with high mosquito populations—are emerging as hotspots. Experts attribute this shift in part to climate conditions and the expanding range of species like Aedes aegypti, commonly known as the yellow fever mosquito.

How to Protect Yourself: The “BITE” Method

Public health officials recommend four key prevention strategies:

• Block access to skin using long sleeves, pants, and EPA-approved repellents
• Install tight-fitting screens on windows and doors
• Trim vegetation to reduce resting areas
• Eliminate standing water where mosquitoes breed

As mosquito season intensifies, awareness and prevention remain critical to protecting both individual and community health.