For years, people have wondered: Can mosquitoes spread Lyme disease? Many patients who don’t remember a tick bite have questioned whether a mosquito might be to blame. Now, groundbreaking new research has delivered a clear, science-backed answer — mosquitoes cannot transmit Lyme disease.

🧬 The Study That Settles the Debate

A major international study published in June 2025 in the open-access journal Parasites & Vectors — led by researchers from Florida International University (FIU) — provides the most definitive evidence to date.

The research team, including FIU biologist Dr. Fernando Noriega, investigated whether mosquitoes could acquire, maintain, or transmit Borrelia burgdorferi sensu lato, the group of spiral-shaped bacteria responsible for Lyme disease. After extensive laboratory testing involving multiple mosquito species, the answer was clear:

“Mosquitoes do not have the biological capacity to efficiently acquire and maintain the bacteria that cause Lyme disease, and they are unable to transmit them naturally or mechanically.” — Dr. Fernando Noriega, FIU

You can also read a plain-language summary of this discovery on The Cool Down.

🔍 What Scientists Discovered

Researchers tested several mosquito species to see if they could acquire or pass along Borrelia. They found that mosquitoes:

• Rarely acquire Borrelia when feeding on infected hosts.

• Rapidly destroy the bacteria inside their gut thanks to an enzyme called trypsin.

• Cannot transmit Lyme, either naturally or mechanically, even when experimentally infected.

The study’s conclusion is simple but powerful: ticks remain the sole competent vectors for Lyme disease.

🕒 Why Ticks Can — and Mosquitoes Can’t

The difference comes down to feeding time and biology.

• Ticks feed for days, giving Borrelia time to activate, multiply, and migrate to the bite site for transmission.

• Mosquitoes feed for minutes, and their digestive system — rich in trypsin — wipes out the bacteria before it can survive.

The mosquito digestive system actually helps protect us. The enzyme trypsin quickly breaks down Borrelia, making transmission impossible. Even when scientists inhibited that enzyme, the bacteria survived only briefly and still couldn’t infect another host.

💬 Why People Think Mosquitoes Spread Lyme

Many people with Lyme disease don’t recall ever being bitten by a tick. Nymphal ticks — the stage most likely to transmit Lyme — are the size of a poppy seed and often go unnoticed. Because mosquito bites are memorable and visible, it’s easy to assume a connection. This study finally explains why that belief persists — and why it’s scientifically incorrect.

That confusion highlights why education and preparation are so important. Knowing what to do after a tick bite can make all the difference. Tick Boot Camp created the Tick Bite Blueprint — a free, science-based guide that walks you through every step of tick safety. It covers how to safely remove a tick, what symptoms to watch for, and when to seek testing or medical care. It’s an empowering tool for every household navigating tick exposure and Lyme prevention.

🌍 Public Health Impact

This discovery is a major win for public health and Lyme awareness. For decades, speculation about mosquitoes, flies, and other biting insects has created confusion. Now, health officials can confidently focus prevention and education efforts on ticks, where the true risk lies.

With rising temperatures expanding tick habitats and extending their active seasons, this clarity is crucial. Misattributing Lyme risk to mosquitoes could distract from the real preventive actions people need to take — such as tick checks, repellents, and early removal.

By ruling out mosquitoes, researchers have narrowed the focus for both scientists and the public, strengthening Lyme prevention and awareness worldwide.

🎙️ Keep Learning with Tick Boot Camp

At Tick Boot Camp, our mission is to educate, empower, and connect the Lyme community through stories and science. To explore more breakthroughs like this one, tune in to our podcast interviews with leading researchers and doctors advancing the field of Lyme disease and tick-borne illness.

You can also listen to our main Tick Boot Camp Podcast, featuring patients, advocates, celebrities, clinicians, and scientists sharing real experiences and expert insights. Every episode is designed to help you believe that healing is possible — and to give you the knowledge to make it happen.

💡 The Takeaway

Mosquitoes can carry dangerous diseases like West Nile, Zika, and dengue — but Lyme disease isn’t one of them. The science is clear: ticks = yes, mosquitoes = no.

Accurate information saves time, reduces fear, and helps people protect themselves and their families with confidence.