In the spring of 2024, Hannah, 12, was spending three to four hours a day catching insects in a local New York City community garden. Hannah would bring her catch home to feed Perry and Terry — her pet praying mantises.

When Hannah started complaining of tiredness, headaches, and leg pain, her mom, Lee Kim — a Pfizer employee — didn’t initially connect her symptoms to a more serious underlying problem. After all, Hannah was an otherwise active, healthy kid.

“Up until this point, the only time we went to see her pediatrician was for her annual health check,” says Lee, a design and change management lead at Pfizer. “I’d never made a sick appointment before.” 

But while on a walk in June, Lee realized only half of Hannah’s face was moving when she smiled. After researching her symptoms on the internet, Hannah and her mom found information that suggested Bell’s palsy, and they should go to the doctor’s office. There, a blood test identified the cause of her progressive symptoms: Lyme disease.

Shining a light on Lyme

Lyme disease is a bacterial infection which is caused by the bite of a black-legged ticks carrying bacteria called Borrelia. Symptoms vary but include fever, headache, fatigue, and a skin rash near the site of the bite. If left untreated, the infection can spread to the joints, heart, and nervous system and cause a range of health concerns.

“Although it was scary to see [Hannah’s] face paralyzed, I’m glad that symptom showed up,” Lee says, adding that it gave them an opportunity to treat it.

After a two-week treatment of antibiotics, Hannah’s symptoms subsided. But she had to release Perry and Terry during her illness, and she has become more cautious about playing in the community garden for fear of another tick bite. 

“For her, it was a traumatic experience,” Lee says. At its worst, “She couldn’t sleep because of the joint ache. She couldn’t drink or eat that well … I can only imagine how people deal with it when they have [persistent symptoms] from Lyme disease because, even for two weeks, it was painful.”

Hannah is looking at the silver lining of her experience, telling Lee that she now appreciates what a blessing it is to be able to smile. Both Hannah and Lee want to share their experience in order to bring awareness to Lyme disease and the importance of proactivity in health.

The potential future of Lyme prevention

The incidence of Lyme disease has increased dramatically over the past 10 years. According to the Centers for Disease Control and Prevention, about 476,000 people may be diagnosed and treated for Lyme disease each year in the United States, and the geographic footprint of cases is growing.

 As Borrelia, the bacteria that causes Lyme disease, spreads through a person’s skin, it often causes a rash around the bite site, though the rash may not be readily visible depending on its location (e.g., under the hairline,) and can be more difficult to detect on certain skin tones. If left untreated, the bacteria can enter and travel through the bloodstream, producing more severe Lyme disease symptoms like inflammation of the brain and spinal cord or arthritis with severe joint pain.

Together with its partner Valneva, a French biotech company, Pfizer is in clinical trials for an innovative Lyme disease vaccine that could prevent Borrelia from being transmitted. The vaccine targets a protein on the surface of Borrelia that the bacteria need to stay alive inside a tick.

“The way this vaccine works is when you immunize people, you get antibodies against a protein on the outside of the bacterium that causes Lyme disease,” explains Raphael Simon, senior director of vaccines research and development at Pfizer and the research lead for the Lyme disease program. When the tick starts to feed on a person, it also takes in the antibodies against the protein, a sort of Trojan horse neutralizing the bacteria in the tick’s gut before it has the chance to transfer to the person.

While precautions for preventing tick bites and checking for ticks after you’ve been outside are important measures, they have limited effectiveness.

“Realistically, a vaccine has the potential to have much greater impact than the current approaches to prevent Lyme,” Raphael says. “That’s really what keeps me and the team motivated — the potential to deliver something that’ll have an impact on people’s health.”

Scientists’ mission and parents’ compassion

Lee visited Pfizer’s office in Pearl River, N.Y., to share Hannah’s story with Raphael and learn about the progress Pfizer is making toward Lyme disease prevention.

Hannah was at school during the conversation, but had prepared a letter for Raphael. The letter, which Lee read aloud in Hannah’s place, ends with two poignant questions: “What are you doing to help prevent Lyme disease? Will there ever be a way for us to enjoy nature without the fear of tick bites?”

Raphael answers Hannah’s questions thoughtfully, with detailed descriptions of how the vaccine may prevent Lyme disease and his hopes for its potential.

“Your story certainly hit home with me,” Raphael notes to Lee. “I also have young kids. They play in the yard. You know, they enjoy time outside. I think about that often. Kids should be free to be kids and enjoy nature and enjoy being a kid without necessarily worrying about things like this happening.” 

At the end of the conversation, Lee thanks Raphael for sharing insight into his work. “I’ll try to translate what we have learned here to Hannah,” she says. “Listening to you and thinking about what you’re doing and what your team is doing makes me feel a little bit safer in the future. And I’m just here to say thank you.”

Raphael responds with a thank you of his own. “Please thank Hannah for all of us as well for being willing to share her story. For all of us working to develop a potential vaccine to prevent Lyme disease, these sorts of stories are very important.”