Pfizer Lyme Vaccine Prevents 70% of Cases in Late-Stage Study as Tick Bites Hit 2017 High
Updated
Updated · The Santa Rosa Press Democrat · Jul 2
Pfizer Lyme Vaccine Prevents 70% of Cases in Late-Stage Study as Tick Bites Hit 2017 High
3 articles · Updated · The Santa Rosa Press Democrat · Jul 2
Summary
Pfizer said in March 2026 that its Lyme disease vaccine prevented infection in 70% of people who received it in a late-stage study, marking a potential new tool against a growing U.S. health threat.
CDC data underscore that need: emergency-room visits for tick bites reached their highest level since 2017 on April 23, while experts estimate nearly 500,000 Americans get Lyme disease each year.
More than 89,000 Lyme cases were reported by state health departments in 2023, though the disease is believed to be undercounted because tick bites often go unnoticed and early symptoms can be missed.
About 90% of U.S. cases occur in the Northeast, mid-Atlantic and Upper Midwest, and incidence has nearly doubled since 1995 as warmer weather, rainfall shifts and expanding deer habitats help ticks spread.