This article has been updated to correct an earlier inaccuracy. As the outdoor season begins across Indiana, there is both good and bad news regarding ticks. The concerning news is that many individuals are discovering ticks on themselves and their pets. However, the positive aspect is that, so far, there have not been significant reports of illnesses or diseases linked to these ticks. This situation, however, may change if proper precautions are not taken, as even a single tick bite can lead to serious infections or viruses.
Lee Green, a senior medical entomologist at the Indiana Department of Health (IDOH), has reported a surge in tick populations this year. "We have received numerous calls, and our field staff are collecting a significant number of ticks," Green stated. Currently, most ticks are in their nymph stage, which makes them smaller and more challenging to detect on both humans and pets. While adult ticks have a higher infection rate, nymphs are known to transmit a greater number of diseases because they are often overlooked due to their size. Green emphasized, "We see the most Lyme disease cases in humans during the nymph season, which is now underway."
Indiana has recently seen the emergence of new tick species, such as the Gulf Coast tick, first identified in the state around 2017-2018. These ticks can now be found in 14 counties, stretching from central Indiana to the southwestern region. "The more we search for Gulf Coast ticks, the more we find them in various areas," Green noted.
Another newcomer is the Asian longhorned tick, which is the first tick to invade the U.S. in the past 80 years. So far, it has only been identified in Dubois, Spencer, and Switzerland counties. While these ticks typically do not bite humans, they pose a significant threat to livestock by transmitting parasites detrimental to cattle. Green highlighted that, although lab conditions show these ticks can carry human pathogens, no cases have been reported yet.
According to Dr. Robert Adams, an emergency medicine physician with IU Health Bloomington, Indiana sees between 300 and 400 tick-related cases annually. While this number may seem high, Adams described it as relatively low. Lyme disease is one of the most common tick-borne illnesses, especially prevalent in the northwest part of the state. A typical symptom of Lyme disease is a target-shaped rash: a red center surrounded by a white circle and then another red circle.
In southern Indiana, illnesses such as Rocky Mountain spotted fever and ehrlichiosis are more frequently reported. Additionally, there’s an emerging concern about ticks carrying two types of viruses that can affect humans: the Bourbon virus and the Powassan virus. These viruses can lead to symptoms like fatigue, headache, and rash, and antibiotics are ineffective against them.
Another serious issue associated with tick bites is alpha-gal syndrome, an allergy to red meat. After a bite from an infected tick, a sugar molecule enters the bloodstream that triggers an immune response, leading to allergic reactions when consuming mammalian products. Symptoms can range from mild issues like hives to severe anaphylaxis. Dr. Adams noted that some individuals may unknowingly have this allergy and may experience unexplained symptoms such as heartburn.
Alpha-gal is primarily transmitted by lone star ticks, which are becoming more common in Indiana. There are two key populations of lone star ticks: one near Lake Michigan and a larger one in southern Indiana. These populations are merging, making them more prevalent around Monroe County.
Indiana is home to six tick species that can transmit diseases to humans, each carrying multiple pathogens:
American dog tick: Spreads Rocky Mountain spotted fever and tularemia. Black-legged tick: Responsible for Lyme disease, anaplasmosis, babesiosis, and Powassan virus. Brown dog tick: Transmits Rocky Mountain spotted fever. Gulf Coast tick: Spreads Rickettsioses, including Rocky Mountain spotted fever. Lone star tick: Carries ehrlichiosis, tularemia, Bourbon virus, and alpha-gal syndrome. Asian longhorned tick: Currently found in four southern Indiana counties, with no reported human disease transmission.Kody Clark from the Monroe County Health Department reported that as of May 8, 20 American dog ticks and 18 lone star ticks were documented through their Citizen Tick Reporter Web app. Most American dog ticks were found indoors, while lone star ticks were often discovered on people’s skin. Clark expects more reports as the season progresses and encourages the public to utilize the reporting app.
Green and Adams agree that the best way to prevent tick-related illnesses is to minimize exposure to ticks. Adams emphasized the urgency of implementing prevention measures now. Recommended strategies include wearing long pants and long-sleeved shirts treated with 0.5% permethrin, and applying repellents containing DEET, picaridin, or oil of lemon eucalyptus on exposed skin. Green also suggests using boot gaiters soaked in permethrin to keep ticks from making contact with clothing.
Conducting thorough tick checks after outdoor activities, even in your own yard, is crucial. Black-legged ticks often attach in hard-to-see areas, making it even more important to check areas like the back of the knees.
Even if a person does not contract a disease from a tick bite, infections can still arise, leading to potential long-term health issues. To deter ticks from your yard, consider landscaping modifications that reduce humidity, as ticks thrive in moist environments. Mow grass regularly to allow sunlight to dry it out and eliminate ground cover that retains moisture. Place play areas in sunny locations and create physical barriers using gravel or wood chips to discourage tick migration.
If you discover a tick attached to your skin, Dr. Adams advises careful removal to ensure the entire tick is extracted. If the tick has been attached for less than 48 hours, the risk of disease transmission is low. However, symptoms may take one to two weeks to manifest. If you experience symptoms such as a rash, fever, or swelling at the bite site, seeking medical attention is recommended. Early treatment with antibiotics can mitigate the impact of transmitted diseases, while it’s important to note that alpha-gal syndrome and the new viruses cannot be treated with antibiotics.
For further questions or reports about ticks, please reach out to Carol Kugler at ckugler@heraldt.com.
