In May, the Centers for Disease Control and Prevention said cases of tick-borne diseases, such as Lyme disease, have been exploding across the U.S. But a new study out Thursday, using a different research method, indicates that the problem is even greater than previously thought.
It found 83 counties, located in 24 states, where ticks carrying disease-causing bacteria had not been documented before.
“Her whole life has changed now, and she’s 6.”
The researchers found this out with a little help from their friends — an army of "citizen scientists" across 49 states who pulled over 16,000 ticks off their bodies, packed them in plastic bags and sent them in for testing.
“The amount of data we were able to collect in two years is equaling some of the data in public health and state health departments that they have been collecting for over 50 years,” said Nathan Nieto, the lead author of the study and associate professor of microbiology at Northern Arizona University. “The sheer numbers have made it so that this is a powerful data set.”
Researchers at Colorado State University and Northern Arizona University set out to assess the realistic, real-time risk of tick-borne disease in the U.S. They worked with the Bay Area Lyme Foundation, which put out the calls for tick submissions. Americans who pulled a tick off themselves, their child or their pet were asked to bag them up and send them in, and report their location and activity at the time they found the tick.
The submissions showed a variety of species of tick, including some that carry pathogens for Lyme disease, which the CDC reports 300,000 cases of a year. Some carried other pathogens that need to be studied further to determine their risk, the researchers said, and some were clean.
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Nieto said the study showed that scientists don't fully understand the tick threat, and that using citizen scientists is a valuable tool in gaining more data. In contrast to the 16,000 ticks sent in by volunteers, researchers like Nieto often pick up only 100 ticks apiece when out in the field collecting them for study.
But Nieto noted that there are limitations to citizen scientists. Researchers can't assume that the tick was picked up in the same geographical area the volunteers were in when they first spotted it, because they may not know how long the tick was on them.
This was the case for Ashley Collins’ 6-year-old daughter, Brooklyn. Ashley, who was not part of the citizen scientists study, noticed about a year ago that her daughter was having unusual symptoms, including an inability to concentrate and a loss of appetite, and was getting sick frequently. “She’s a very sick girl,” Collins told NBC News recently.
She took Brooklyn to doctors for a variety of tests, none of which gave answers. After several months, a doctor asked about tick exposure.
“I said, 'Sure, we live in Arkansas, we’re outdoors all the time,' ” Collins said. “The doctor said, ‘This is Lyme.’” According to the CDC's 2016 map of tick-borne diseases, Arkansas has a moderate risk of Lyme, with 7,094 tick-borne diseases reported from 2004 to 2016.
Lyme often announces itself with a bull's-eye rash and feverish symptoms. But for roughly 25 percent of cases, it’s less obvious and takes many doctors and tests to diagnose.
Collins said it never occurred to her that it could be Lyme disease. “I thought it was rare,” she said. “Mowing the grass and the garden and all that typical stuff and the number of ticks we had all over us, it never crossed my mind at all."
A variety of factors contribute to the rise of tick-borne diseases, Nieto said, including changing migration patterns of people and animals who are carrying them to new areas, and warming temperatures from climate change, which creates favorable conditions for ticks to spread.
Better awareness of the threat can help families like the Collinses. Nieto said families who see ticks should “remove them in a careful way, get them tested and get themselves tested.”
Collins wants other families to be aware of the risk so they might be spared what her daughter is going through. Doctors told her that because the tick bite came probably months before the diagnosis, the infection caused brain inflammation and is harder to treat and cure.
“I feel like I could not keep her safe, like I failed her in a lot of ways,” she said, noting that Brooklyn could even pass the infection on to her future children. “Her whole life has changed now, and she’s 6.”
Alvaro Toledo, assistant professor of entomology at Rutgers University in New Jersey, was encouraged by the study. He said the huge number of submissions shows that it can be a critical front in combating tick-borne illness.
“I’m impressed at the volume of the response,” he said. “It shows this approach is a great complement to what local officials and researchers are doing.”