See the incidence of Lyme disease across all 50 states in 2023

See the total number of Lyme cases per state in 2023

New York, Pennsylvania, and Massachusetts had the highest total number of Lyme disease cases in 2023. New York had more than 22,000 cases that year. Maine had one of the highest Lyme incidence rates of disease that year—213 per 100,000 people—but only 2,942 cases overall.

Search Lyme disease incidence in your county

The searchable database at the bottom of this webpage allows users to check the reported incidence of Lyme disease in US counties and Canadian health regions. In 2022, for example, Baltimore County in Maryland had a rate of about 34 probable and confirmed cases per 100,000 people. Arlington, County in Virginia was less than half of that for the same time period.

Lyme disease is the most common vector-borne illness in the US

In the US, ticks account for 90% of all disease transmission from bites, including mosquitoes. And Lyme disease is the most common vector-borne disease in the US overall, with estimates suggesting there are about 475,000 Lyme cases annually across the nation.

Lyme disease was first identified in Lyme, Connecticut in 1975

A cluster of 51 children and adults in the town all began experiencing uncommon arthritic symptoms and the cases were reported to the state health department. A quarter of the cases were preceded by a skin lesion. The patients tended to live near the woods.

More than 1 in 7 people worldwide have had Lyme disease

Research published in 2022 suggests that 14.5% of the world's population has contracted Lyme disease. Researchers arrived at that estimate by analyzing the presence of Lyme disease antibodies (indicating prior infection) across 89 studies conducted between January 1984 and December 2021. The works collectively included blood samples from more than 150,000 people. (Some user may encounter a paywall.)

Lyme disease may cost about $1B annually in the US

The economic burden of the disease in this estimate includes direct medical costs and societal costs, including productivity losses. It does not include suspected, undiagnosed, or nonacute cases, which would push that figure upward.

Read a study about racial differences in Lyme disease diagnosis

The research published in September 2025 examined differences in Lyme disease diagnosis among Medicaid and Medicare beneficiaries using data from 2016 to 2021. It notes that though US Lyme disease surveillance data indicates more than 90% of diagnosed Lyme cases are among white people, people of color—particularly those who identify as Black or African American—have higher rates of more severe disease of Lyme, with symptoms including arthritis and neurologic impacts.

See MS prevalence by region in the United States

This map underscores that people in the northeastern United States have more cases of the disease as compared to the south, west, and midwest. On an individual level, these numbers may still differ based on genetic makeup and other factors irrespective of where people live.

10 locally acquired malaria cases were reported in the US in 2023—a surprise

The cases, reported in Florida, Texas, Maryland, and Arkansas, broke a 20-year streak since there had been no reported locally acquired mosquito-transmitted malaria in the country since 2003, when there was a case in Florida.

Two Lyme disease vaccines were in development in 2026

As of early 2026, there was no vaccine for Lyme disease available. One candidate vaccine, VLA15, was in later-stage clinical trials. Another designed to provide seasonal protection was licensed to a pharmaceutical company in 2025, and was planned for human clinical trials.

Erythema migrans rash is common in Lyme—but it often doesn't look like a bull's-eye

The US Centers for Disease Control and Prevention states that this rash occurs in roughly 70% or more of Lyme disease patients, and typically occurs at the site of a tick bite. The rash may expand slowly over several days and feel warm to the touch, but it's rarely itchy or painful. As it grows, areas of it may clear—creating a target or "bull's-eye" appearance.

81% of Florida's leprosy cases occur in central Florida, raising concerns

Researchers noted in 2023 that about one-fifth of new US leprosy cases were reported in the central part of the Sunshine State. What's more, about a third of the new US cases overall appear to have been acquired locally, raising questions about whether the disease is now naturally occurring in parts of the southeastern US.

See Virginia's spike in HFMD cases in 2025

The state's own tracking showed a significant jump in HFMD cases in July 2025 as compared to the prior few years, and that more people were visiting the emergency room and urgent care centers for the disease, but epidemiologists could not explain why the numbers were so high.

Wearing tick repellent, covering up, and performing tick checks are the best Lyme prevention

Spraying repellents onto your clothes—and reapplying them—or donning impregnated bug-repelling clothes can help keep ticks away. Effective sprays include DEET, picaridin, or permethrin. Bug spray applied to the body should be applied on top of sunscreen, and only after the sunscreen has dried.

Genetic engineering mice is one idea to reduce Lyme disease transmission

Wild white-footed mice are the main carriers of Lyme. A research team is hoping to genetically engineer mice, using CRISPR, to make the animals immune to Lyme. They're proposing a field trial where they would insert a gene with an antibody to Lyme infection to break the disease transmission cycle on a private island and then try it in Nantucket if that goes well. Simply killing the mice isn't an option because it would upend food webs. Unlike traditional vaccines, this "heritable immunization" would pass from one generation of mice to the next.

As of 2026, the majority of US states have unsafe radon exposure levels

Alaska, South Dakota, Pennsylvania, Ohio, and Washington top the list of states with exposure levels above 4 picocuries per liter for this naturally occurring radioactive gas. While these state-level averages vary from one county, municipality, and home to another, the EPA encourages those in the highest-risk states to test their homes.

Between 2006 and 2021, 444 people died from lightning strikes in the US

The National Oceanic and Atmospheric Administration reports that the odds of being struck by lightning in one's lifetime are one in 18,864. Participation in outdoor activities during the summer months in Florida, Texas, and Colorado increases one's risk of exposure.

The 10 best US states to retire in, ranked

Out of all 50 states, Delaware was recently deemed the number one state for a happy retirement. That ranking is based on a few factors, including weather, affordability, healthcare, crime, and more. Want to know what other states ranked in the top 10 as of 2024? Click here to find out.

Browse a list of the most important scientific breakthroughs from each state

Although scientific discoveries involve experimentation, analysis, and collaborations among many individuals across a variety of locations, some observations, advancements, and breakthroughs have their origins in facilities within the US. These include the polio vaccine in Pennsylvania, the breathalyzer in Indiana, the observation of Pluto in Arizona, and the invention of nylon and Teflon in Delaware. (Some readers may experience a paywall.)

Murder rates spiked in the US after COVID-19, and then declined in 2023

Criminologist and former investigator Jillian Peterson says whether a murder is solved in the US is nearly up to the flip of a coin, with the clearance rate for murder cases being about 50%. The US, which has more guns than citizens, has about roughly five gun homicides per 100,000 residents, resulting in the 28th-highest rate of deaths from gun violence compared to the rest of the world.

Explore more statistics about cancer

The American Cancer Society's Cancer Statistics Center estimates there will be more than 2 million new cancer cases and almost 620,000 cancer deaths in the US during the course of 2025. Breast, prostate, and lung cancers remain the most prevalent. This interactive tool provides detailed statistics on cancer incidence, mortality, and survival rates, allowing users to explore data by state, cancer type, demographics, and risk factors.

To be in Connecticut's 1%, you'd need to earn more than $1M per year

That makes Connecticut the most competitive state in the country when it comes to joining the 1%. This map outlines how much it takes in the other states.

25% of US households had no regular income as of 2024

Some states had higher shares of no-income households than others: West Virginia, for instance, had a national high of 34% of households with no income. These states tend to have older populations, higher rates of disability, and lower median incomes overall. In such contexts, a larger portion of households rely on non-earned income sources or report no income during the survey period.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

Missouri had the fastest job growth rate in 2025

Between 2024 and 2025, Missouri had a 1.7% job growth rate—representing the percent increase in jobs in a particular state over the course of a year. North Carolina and South Carolina trailed Missouri with annual job growth rates of 1.5% and 1.3% respectively.

Rhode Island plans to impose a ‘Taylor Swift tax’ on second homes

Starting in the summer of 2026, the state will impose a new property tax surcharge on second homes valued at, or over, $1M that aren’t used as primary residences. Some are calling it the “Taylor Swift tax,” given that Rhode Island is home to the pop star’s gargantuan historic beach house.

This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

View the ten deadliest tornadoes in US history.

Between 10 million and 50 million people in the US develop rashes from poison ivy, poison sumac, and poison oak each year.

Experimental hantavirus vaccines and therapies, still under development, have long been funded by the US military.

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

The USPS spent $3.97B in 2024, accounting for .058% of the federal budget.

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

Ebola species have historically been named after where they were discovered, stigmatizing residents who live there, including Bundibugyo, in Uganda.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

Massive blooms of microscopic plankton called dinoflagellates produce the neon blue light seen in glowing tides.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

About 2,000 US babies are born annually without some portion of their limbs, potentially leading to a lifetime of pricey prosthetics.

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

A century of Billboard issues documenting the evolution of popular music.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Elk Cloner, the first computer virus to spread in public, was written as a practical joke by Richard Skrenta, a Pittsburgh high school student.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'