Wilderness hikes are a summertime favorite, but in regions where Lyme disease is present, one tick bite can have lifelong health impacts. Even with preventative measures such as wearing full-coverage clothing and scanning skin for ticks regularly, around 475,000 people contract the disease each year. As deer ticks, the ticks which carry Lyme disease, increase in prevalence across the US, researchers are working to develop appropriate vaccines to combat contraction. While a vaccine is not yet available, researchers from the University of Massachusetts Medical School are seeing promise in single-dose antibody shots.

Rather than prompting the body to develop its own antibodies like traditional vaccines, the new method delivers a single anti-Lyme antibody to prevent disease. Called Lyme PrEP, the shot would be a once-a-year seasonal immunization delivered in April at the beginning of tick season. In phase 1 clinical trials, the shots appeared to be effective in preventing disease for the whole typical nine-month tick season.

Previous attempts to create a Lyme vaccine were largely unsuccessful due to the number of booster shots required and questions regarding efficacy, but the new method’s approach doesn’t seek to prompt antibodies but rather uses a single introduced antibody to kill harmful bacteria in the tick’s gut after they bite. This prevents the bacteria from getting into the human host in the first place. In tests on animals, it proved to be 100 percent effective at preventing illness. Essentially, it’s a defense mechanism that prevents potential infection from ever reaching the human bloodstream.

More human trials are required to ensure efficacy, but researchers are confident that they will have a treatment available for the public by 2023 or 2024.