One of the most basic pieces to the Lyme puzzle in the Hoosier State is the presence of the blacklegged tick. According to Dr. Robert R. Pinger from Ball State University, the blacklegged tick population expanded from 4 counties in 1987 to 59 counties in 2007. There are 92 counties in Indiana.

In 1993, Dr. Pinger discovered an established population of blacklegged ticks in Jasper County after a resident, who had been diagnosed with Lyme Disease in 1985, sent a vial of ticks that had been collected from a site just south of the resident’s home. Once the larger population was studied, Dr. Pinger found that 33% of the adult ticks and 9% of the nymphs were infected with spirochetes – the bacteria that causes Lyme.

In 2018, researchers at Indiana University also reported a rise in the number of blacklegged ticks in the state. These same researchers also stated that the fact that the blacklegged tick populations were rising could also mean more cases of Lyme in humans in the coming years.

The number of CDC-confirmed human cases of Lyme nearly tripled between 2012 and 2016 from 64 to an estimated 152, but this CDC figure has been on a steady rise since, at least, 2006. And, in reality, 2016 figure could be as high as 1,520 Lyme cases, when factoring in the CDC’s margin of error.

The Indiana Department of Health statistics do not record an increase in Lyme cases, though, because the agency ceased keeping accurate records of confirmed cases in 2003 – just as the upward trend was beginning.

The available statistics and studies seem to point to increased chances of infection, and actual cases of Lyme disease, in Indiana. However, the full scope of the problem in the Hoosier State is clouded by faulty diagnostic testing and narrow CDC guidelines, making harder for well-meaning physicians to recognize the signs and symptoms of this elusive, often debilitating disease.

To bridge this knowledge gap, Indiana Lyme Connect promotes CME courses and other resources to enhance physicians’ understanding of Lyme Disease. For more information on courses, research, and other resources, please visit our CME & Resources page.

For more information on current diagnostic tests and the CDC guidelines, please visit our Diagnosis page.