Tick-borne illnesses like ehrlichiosis, Lyme disease and Rocky Mountain spotted fever are on the rise in Illinois, and outdoor workers like farmers are at higher risk than those who spend more time indoors. University of Illinois Urbana-Champaign Ph.D. candidate Sulagna Chakraborty and her colleagues at Illinois led a new study on the subject that surveyed 50 Illinois farmers to learn about their awareness of the problem and engagement in tick-prevention efforts. Chakraborty spoke to News Bureau life sciences editor Diana Yates about what they found.
What are the trends in tick abundance and tick-borne disease in Illinois?
Ticks have been present in Illinois since at least 1905, but in recent times there has been an exponential increase in ticks and tick-borne diseases in the state. The geographic expansion of ticks is driven by changes in climate and the movement patterns of hosts such as birds, small mammals and white-tailed deer. Land-use changes also affect the availability of suitable habitats and strongly influence tick abundance. In particular, the tick species that can cause the most harm – such as the blacklegged tick, American dog tick, lone star tick and the Gulf coast tick – have expanded into new areas in Illinois and across the Midwest.
How might farm animals and wildlife be affected?
Ticks are known to parasitize domestic animals, livestock, companion animals and wildlife. Ticks are considered vectors because they can pick up an infection during a blood-meal from one host and transmit it to another in their next meal. Among livestock, ticks can cause bovine anaplasmosis, bovine babesiosis, theileriosis, cattle fever and other diseases. Ticks can be a nuisance and are known to cause infections in cats, dogs and other companion animals.
If cattle and wildlife interact in nature – for example, during grazing – this can promote the transmission of several zoonotic and vector-borne diseases such as anaplasmosis, tick-borne encephalitis and tularemia. If farm animals are not regularly protected with safe-to-use acaricides and groomed for ticks, they are at risk of becoming infested and can pass those ticks to their human handlers.
How informed were the farmers you surveyed about the risks to them and their animals?
Awareness of ticks and the diseases they transmit varied. Beef producers and mixed-commodity farmers were more knowledgeable on this topic than crop producers. All of the farmers we surveyed knew that ticks can spread diseases to humans and a majority knew that ticks also spread diseases to animals.
Farmers who reported being bitten by ticks in 39 counties in Illinois had moderate knowledge about the tick species that are present in the state. Fewer respondents said they could identify the medically important tick species. They also were aware of the types of habitats where they might be exposed to ticks but did not know which animals act as reservoirs of infection or help move the ticks around. Depending on the farm type, the sources of information used by farmers for ticks and tick-borne diseases were not always accurate and reliable. We also found that farmers were not very concerned about contracting tick-borne diseases.
Did the farmers know how to protect themselves?
Most farmers said they performed regular tick checks on themselves after spending time outdoors and sometimes take one or more preventive measures. About half of the respondents believed that following tick-prevention measures was helpful but only 8% respondents were satisfied with the precautionary measures currently taken.
Interestingly, we found that farmers implement more preventive measures against ticks for their pets than for themselves. Those with cattle were even less likely to use prevention measures on their livestock.
Did you identify significant gaps in their understanding of the risks?
We found several critical gaps in their understanding. First, farmers were not knowledgeable about the main vectors of tick-borne illness in their counties. Second, they were not aware of tick-prevention measures for themselves such as wearing permethrin-treated clothing. Third, farmers were not taking enough measures to protect their cattle with tick repellents or topical acaricides. Fourth, they were not aware of where they would go to seek treatment if they had a tick-borne illness. And finally, as stated before, they had very low concern about contracting a tick-borne disease. The level of knowledge also varied depending on the main commodity produced by the farmer.
What kinds of programs would help fill those gaps in knowledge?
We recommend basic tick and tick-borne disease training for all residents of Illinois because everyone is at risk of being exposed to tick bites depending on their occupations, leisure and outdoor habits. For farmers, providing farm-specific training on ticks, tick-borne diseases and their risks of exposure would bolster their knowledge of the necessary measures to take – not just for their companion animals but also for themselves and their livestock.
Increasing the reliance of farmers on reliable sources of information on ticks and tick-borne diseases – such as Extension educators and veterinary and medical professionals – instead of conventional media and family and friends will allow farmers to keep up with the latest scientifically valid information on the subject. This will allow them to better protect their farm, their animals and their families.