Maryland Lyme Cases Double Since 2020, Sparking State Awareness Push

Maryland's Department of Health has launched a statewide Lyme disease awareness campaign following a dramatic surge in cases, with infections nearly doubling since 2020, according to the latest state data. The initiative, rolled out as spring tick season begins in April and peaks in May-June and September-October, urges outdoor enthusiasts to adopt preventive measures like using insect repellent, wearing long sleeves and pants, and conducting thorough tick checks after hikes in grassy or wooded areas. Lyme, caused by the bacterium Borrelia burgdorferi and spread by blacklegged ticks, remains the state's most prevalent tick-borne illness, with Maryland ranking among the nation's highest in cases.

Emergency room visits for tick bites are spiking across Maryland and the Northeast, hitting levels not seen in nearly a decade, per new CDC data. The region reports more than triple the typical cases for this time of year, prompting warnings about Lyme alongside Rocky Mountain spotted fever. Nationally, Lyme affects an estimated 476,000 patients annually, with 31 million Americans bitten by ticks each year; prompt removal of attached ticks within 24 hours significantly reduces transmission risk.

University of Maryland researchers warn that rising temperatures could shift Lyme hotspots westward, easing risks in densely populated central areas while elevating them in cooler western counties like Garrett and Allegany. A March 25, 2026, study in Royal Society Open Science used two decades of data to model blacklegged tick lifecycles under warming scenarios, predicting western Maryland as a new primary hot spot under high-emission paths. State health leaders emphasize vigilance statewide, aligning the campaign with national Lyme Disease Awareness Month in May.