When ticks burrow their tiny little heads into your flesh, their backwash can transfer a bacterium into your blood. If you’re particularly unlucky, the tick that just lanced your skin could be packing Borrelia burgdorferi—the bacteria that cause Lyme disease. As a recent release from the Centers for Disease Control and Prevention makes clear, however, there are a whole lot of unlucky Americans out there: the incidence of Lyme disease in the U.S. is ten times higher than we thought, and it’s probably higher still.
Each year, more than 30,000 cases of Lyme disease are reported to CDC, making it the most commonly reported tick-borne illness in the United States. The new estimate suggests that the total number of people diagnosed with Lyme disease is roughly 10 times higher than the yearly reported number. This new estimate supports studies published in the 1990s indicating that the true number of cases is between 3- and 12-fold higher than the number of reported cases.
Normally, if a Lyme disease-packing tick bites into you and you promptly, but gently, take it out (head and all) you’ll be safe from Lyme disease. But if you don’t get it in time, you could face a rash, fever, fatigue and pain. If it gets this far, a course of antibiotics normally clears everything right up.
“Scientists have long suspected that Lyme disease, the number one vector-borne illness in the U.S., is significantly underreported,” says Chemical and Engineering News.
“We know that routine surveillance only gives us part of the picture and that the true number of illnesses is much greater,” says Paul S. Mead, chief of epidemiology and surveillance activity for CDC’s Lyme disease program. Previous estimates of disease incidence have been based only on cases reported by doctors.
There’s still some uncertainty about how Lyme disease occurs and recurs. But heightened incidence of Lyme disease infections plays well with the idea that so-called Chronic Lyme Disease is actually just a case of people becoming reinfected with the disease.
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