Ottawa, IL – Last week, LaSalle County Health Department Environmental Health staff was notified by the
Illinois Department of Public Health that a Lone Star tick was collected during a tick drag conducted earlier this
year. All ticks that are collected during the drags are submitted to the University of Illinois – Illinois Tick
Surveillance Program for identification and disease surveillance data collection. The tick, which was collected
in May, is the first Lone Star tick to be identified in LaSalle County.
Tick drags help determine which ticks of public health concern can be found in the county. LaSalle County
The Health Department plans to conduct additional tick drags in 2024. Future tick drags will focus on looking for
additional Lone star ticks to determine if there is an established population. The Centers for Disease Control
and Prevention’s (CDC) criteria for “established” ticks is at least six ticks or two life stages (larvae, nymphs,
adults) collected in a single year. Criteria for “reported” ticks is the identification of one to five ticks of the same
life stage.
While this information comes at a time of the year when the risk is minimal, it is important to keep in mind that
the weather begins to warm up next year and individuals are spending more time outdoors. According to the
IDPH Tick Surveillance website, Lone star ticks can transmit Ehrlichia chaffeensis and Ehrlichia ewingii (which
cause human Ehrlichiosis), Francisella tularensis (tularemia), Heartland virus (Heartland Virus disease),
Bourbon virus (Bourbon virus disease), and Southern tick-associated rash illness (STARI). Lone star ticks are
very aggressive ticks that bite humans. The adult female is distinguished by a white dot or “lone star” on her
back. The nymph and adult females most frequently bite humans.
Growing evidence suggests that alpha-gal syndrome (AGS) may be triggered by the bite of lone star ticks;
however, other tick species have not been ruled out. The lone star tick is most active from April through the
end of July. The lone star tick is not believed to transmit the bacteria that causes Lyme disease (Borrelia
burgdorferi). Anyone experiencing a rash or any unexplained illness accompanied by fever following a
tick bite should consult their physician.
The Illinois Department of Public Health (IDPH) has an interactive map where this data can be found at:
https://idph.maps.arcgis.com/apps/MapSeries/index.html?appid=976061db733441eb977ef5cf2facd5c4&fbcl
id=IwAR2_Na7k-1wCC1KelnkuArMznHc6voaZvkZ-sehe_eI1xGwx_aDwr6PyytI.