Lyme Disease in Texas and the Southern United States
Blacklegged ticks have been identified in Texas.
Researchers continue to study Lyme disease in the South.
Tick-borne illnesses may be underrecognized in southern states.
Lyme disease has traditionally been associated with the Northeast and Upper Midwest. However, investigators continue to report evidence of tick-borne illnesses in parts of the southern United States, including Texas.
Researchers have identified blacklegged ticks (Ixodes scapularis) and western blacklegged ticks (Ixodes pacificus) in multiple Texas counties. Both species are capable of transmitting Borrelia burgdorferi, the bacterium associated with Lyme disease.¹
Blacklegged Ticks Identified in Texas
According to Rebecca Eisen and colleagues, blacklegged ticks were identified in 71 of 254 Texas counties.¹
The investigators reported that:
- 26 counties had established I. scapularis populations
- 45 additional counties reported detected populations
- Surveillance limitations may underestimate actual distribution
The authors emphasized that the absence of records does not necessarily mean ticks are absent.
“Lack of tick records from a county does not imply that ticks are absent from that county.”¹
Lyme Disease Exposure in White-Tailed Deer
Meanwhile, investigators led by Adetunji from Texas A&M University examined the seroprevalence of B. burgdorferi antibodies in 1,493 white-tailed deer collected during the 2001–2015 hunting seasons in Texas.²
Using ELISA testing, approximately 4.7% of deer samples were seroreactive for B. burgdorferi.²
The authors noted that positive samples correlated with years in which Texas reported higher numbers of human Lyme disease cases to the CDC.
Only 0.5% of samples were positive by IgG western blot.²
The investigators also cautioned that standardized western blot interpretation in white-tailed deer remains limited.
Surveillance Challenges in the Southern U.S.
The authors highlighted an important public health concern: surveillance of ticks and tick-borne illnesses remains inconsistent across many regions of the United States.
According to Eisen and colleagues:
“The lack of routine systematic surveillance across the continental United States of ticks of public health importance hampers our ability to define their current geographic distributions.”¹
These surveillance gaps may make it more difficult to fully define the distribution of tick-borne illnesses in parts of the South.
STARI and the Lone Star Tick
An additional tick-borne illness in the South is southern tick-associated rash illness (STARI), sometimes referred to as Masters disease.
STARI is associated with the Lone Star tick (Amblyomma americanum) and can resemble Lyme disease clinically.⁵
Unlike Lyme disease, there is currently no standardized diagnostic test for STARI.
This distinction is important because some patients in southern states may develop Lyme-like symptoms following tick exposure even when standard Lyme testing is negative.
Emerging Tick-Borne Illnesses in the South
The investigators concluded that tick-borne illnesses deserve continued attention in the southern United States.
“It’s important for people to be aware that there may be ticks in areas where they haven’t seen them previously,” Eisen stated.⁶
As tick habitats expand and surveillance improves, clinicians may increasingly encounter Lyme disease and Lyme-like illnesses outside traditionally recognized endemic regions.
FAQ: Lyme Disease in the South
Is Lyme disease present in Texas?
Studies have identified blacklegged ticks and evidence of B. burgdorferi exposure in parts of Texas, though Lyme disease rates remain lower than in highly endemic northeastern states.
Can blacklegged ticks live in the South?
Yes. Investigators have identified Ixodes scapularis ticks in multiple southern states, including Texas.
What is the difference between STARI and Lyme disease?
STARI is associated with the Lone Star tick and can resemble Lyme disease clinically. However, the exact cause of STARI remains uncertain and no standardized diagnostic test currently exists.
Related Articles:
References:
- Eisen RJ, Eisen L, Beard CB. County-Scale Distribution of Ixodes scapularis and Ixodes pacificus in the Continental United States. J Med Entomol. 2016.
- Adetunji SA, Krecek RC, Castellanos G, et al. Seroprevalence of Borrelia burgdorferi antibodies in white-tailed deer from Texas. Int J Parasitol Parasites Wildl. 2016;5(2):168-174.
- Feder HM Jr., Gerber MA, Luger SW, Ryan RW. Persistence of serum antibodies to Borrelia burgdorferi in patients treated for Lyme disease. Clin Infect Dis. 1992;15(5):788-793.
- Fallon BA, Keilp JG, Corbera KM, et al. A randomized, placebo-controlled trial of repeated IV antibiotic therapy for Lyme encephalopathy. Neurology. 2008;70(13):992-1003.
- Masters EJ, Grigery CN, Masters RW. STARI, or Masters disease: Lone Star tick-vectored Lyme-like illness. Infect Dis Clin North Am. 2008;22(2):361-376.
- Rapaport L. Ticks Carry Lyme Disease in Almost Half of U.S. Counties. Scientific American. January 19, 2016.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
I would like to thank you for writing this and studying Lyme disease in Texas. I am a chronic Lyme disease sufferer who has lived in Texas my whole life. I have had Lyme for decades, but it was only recently diagnosed in 2017, after 8 years of searching for an answer. I have been told by several doctors including neurologists, rheumatologists, etc. that “There is no Lyme in Texas.” Even when I presented charts that said otherwise. I also supplied a chart that showed the presence of Lyme in dogs in Texas and they still said no, no Lyme in humans in Texas! Too much money is to be made by big pharma treating all the symptoms and not treating the people whose lives are being ruined with simple antibiotics. That would be too inexpensive and not enough money for pharmaceutical companies. And let’s face it, we know those companies are in our elected officials pockets on both sides of the isle!
So, thank you, thank you, for doing what you are doing and please do not stop!
Thanks for sharing your frustration.