Participants will receive three doses of the vaccine, called VLA15 or a placebo, followed by a booster dose.
“As rates of Lyme disease rise globally, it’s more important than ever to provide people with a new option to help protect themselves from the disease,” Annaliesa Anderson, Pfizer’s senior vice president and head of vaccine development, said in a release. more important.” .
VLA15 is the only Lyme vaccine in clinical development, Pfizer said in a statement. The bacterium it targets, Borrelia burgdorferi, is a major cause of tick-borne disease and “has so far demonstrated strong immune responses and a satisfactory safety profile in preclinical and clinical studies”.
Pfizer said it could submit applications for approval from the U.S. Food and Drug Administration and the European Medicines Agency in 2025 if trials show the vaccine is safe and effective.
What is Lyme disease?
Lyme disease is the most common vector-borne disease in the U.S. and is becoming more common in more areas, according to the Centers for Disease Control and Prevention.
An estimated 476,000 Americans are diagnosed and treated for Lyme disease each year, although the CDC says that may be an excess because people are sometimes treated without official confirmation that they have the disease.
The only vaccine previously available in the United States was discontinued in 2002.
Lyme disease symptoms
Fever, chills, body aches, swollen lymph nodes, stiff neck, shortness of breath, headache, fatigue, and rash are all typical symptoms of Lyme disease.
When you are bitten by a tick, you usually see a small red bump that looks like a mosquito bite. But after 3 to 30 days, if the rash develops and expands from the red area and looks a bit like a bullseye, you may have Lyme disease.
Doctors call this rash erythema migrans. Usually, it expands slowly. It’s usually not itchy or painful, but the area may feel a little warm when you touch it.
This rash occurs in 70 to 80 percent of people with Lyme disease, and some people have it on more than one area of their body.
According to the CDC, if left untreated, the infection can spread to the joints, heart and nervous system. This can cause joint pain and swelling.
After a few weeks to months, the membranes around the brain may also swell, temporarily numb one side of the face and “brain fog”: forgetfulness or confusion.
How people get Lyme disease
Most commonly, the black-legged tick, also known as the deer tick, carries Lyme disease. They live in the Northeastern United States, the Mid-Atlantic and the upper Midwest. Lyme disease-carrying western blacklegged ticks can be found along the Pacific coast.
Most people develop Lyme disease in the spring and summer. That’s when immature ticks, called nymphs, are most actively feeding, and it’s also when most people are walking around outside, through areas of grass and dense trees where the bugs like to hang out.
What to do if bitten
Ticks can be small: Deer ticks can be as small as a needle, so look for them carefully.
Removing ticks within 24 hours reduces the risk of Lyme disease. The longer the tick is attached to the body, the more likely the person is to become infected. Use tweezers to pull down the tick carefully and steadily, grabbing it by the mouth or near the neck. Then apply an antiseptic to the infected area.
If you are bitten and develop symptoms, call your doctor right away. Even if your symptoms go away, you should still see your doctor.
Lyme disease treatment
The standard treatment for early-stage Lyme disease is oral antibiotics. According to the Mayo Clinic, 14- to 21-day courses are generally recommended, but some studies show that 10- to 14-day courses are just as effective.
If the central nervous system is affected by disease, antibiotics can be given intravenously for 14 to 28 days. This treatment clears up the infection, but it may take more time for you to recover from symptoms. Side effects of this treatment may include low white blood cell counts, diarrhea, or infection with other antibiotic-resistant organisms not related to Lyme disease.
According to the Mayo Clinic, people who are given antibiotics early in the disease usually make a full recovery. Patients who are treated later in the infection may take longer to respond to treatment.
The CDC recommends using repellants with at least 20% DEET and avoiding tall grass forest areas where ticks are most common.
Check for ticks daily and shower often if you spend a lot of time outdoors. A towel can help remove unattached ticks.
When you’re outside, cover up. Wear long sleeves, long pants, and a hat when walking or hiking in the woods.
Your dogs and cats can also bring pests indoors, so check them out and keep your yard tick-proof. Clear leaves and brush away where ticks like to hide. Keep your lawn mowed.
More facts about ticks
These arachnids cannot fly or jump, but wait for their hosts—whether mammals, birds, reptiles or amphibians—to feed while resting on the tips of grasses and shrubs. They grab leaves and grass with their shins, a pose called “exploration.”
When the host passes by, the tick climbs up to find a place to bite.
In addition to Lyme disease, tick bites cause at least 20 known diseases.
CNN’s Elizabeth Landau contributed to this report.