When it comes to Lyme disease, where you live matters.
"Your home—and by that I mean the surrounding geography, including the environment, demographics, and your behavior—all can have an impact on exposure to Lyme," says Frank Curriero, a professor of epidemiology in the Johns Hopkins Bloomberg School of Public Health and director of its Spatial Science for Public Health Center.
Lyme disease, a serious infection transmitted by the bite of a blacklegged tick, is the most common vectorborne illness in this country. Initial symptoms include fever, headache, fatigue, and a characteristic bull's-eye rash called erythema migrans. At this stage, which lasts from a few days to several weeks, treatment with antibiotics is important to prevent such chronic complications as joint inflammation and neurological issues.
What has become most worrisome, experts say, is that these creatures (they aren't insects but rather arachnids, relatives of spiders and scorpions) are traveling to locations where they were unheard of in previous years.
Inspired by the popularity of the JHU COVID-19 dashboard, scientists from the Bloomberg School and the JHU School of Medicine teamed up to design a Lyme disease dashboard, hoping to draw public attention to this pervasive and often debilitating illness and to encourage additional research. The researchers introduced their tool in PLOS One in December 2021.
"It's a great example of how we can collaborate across the university," says John Aucott, an associate professor of medicine and director of the Johns Hopkins Lyme Disease Research Center, who is part of the project. "I know nothing about spatial analysis, and they know nothing about the care of people with Lyme disease. We can do something together that neither one could do alone."
While the COVID-19 dashboard provides the public with real-time data on global coronavirus infections and deaths, the Lyme tracker can't do that because federal health officials release statistics about the disease just once a year. Thus, its creators decided to focus on Lyme through a series of maps that illustrate factors influencing its spread, including geography, environment, and socioeconomics. A color-coded map depicts Lyme rates by county, with pale yellow representing near-absence of the disease and deep red for areas with the highest incidence.
Aucott points out that Lyme is a geographically expanding disease, and "this dashboard will allow people to see that Lyme is coming their way," he says. "That way, doctors and patients will consider this as a possible diagnosis, whereas 10 years ago they wouldn't have."
Lyme-carrying ticks are moving north into Canada and south and west from the East Coast, Aucott says. Rising temperatures from climate change and forest clearing for suburban development are disturbing the delicate eco-balance, widening the range of conditions favorable to Lyme. Among other things, it's causing an increase in the population of white-footed mice, the primary host of ticks early in their life cycle.
Because the Centers for Disease Control and Prevention only releases Lyme disease surveillance numbers annually, it's difficult to track trends or post numbers in real time. Thus, the dashboard's initial launch in May 2021 only used available data from the United States and Canada. The researchers are currently seeking information from additional sources, including Google Trends, a free data exploration tool that suggests where Lyme is moving based on public searches, insurance claims, and diagnostic laboratory test results.
"There is a huge thread throughout the Lyme disease world that it is greatly underrepresented because we don't have the best data for it," says Cara Wychgram, a research data analyst in the spatial science center.
About 35,000 cases are reported to the CDC annually, though both the federal agency and Lyme experts believe this is a dramatic underestimate. "It's at least 10 times higher," Aucott says. "We know this from looking at insurance claims," he says. "Doctors don't always submit CDC reports, but they always submit their bills," he says.
The dashboard also includes environmental and sociodemographic information culled from the U.S. Geological Survey, the National Oceanic and Atmospheric Administration, the Department of Agriculture, the U.S. Census, and several Canadian sources.
"We didn't want to just build a dashboard but rather a website that contains other information that helps you understand and interpret the information," Curriero says. Instead of a map that shows only cases, the site also includes map layers that explain the data, including where it comes from and how to interpret it.
Ultimately, the researchers plan to expand the site into a global resource for researchers, policymakers, public health officials, and the general public. "There's a plethora of data sources, and we want them all," Curriero says. "Taken together, they can make a surveillance system that is unique and better than anything we have now."