Managing Ixodes pacificus bites

1.0 CME. This presentation provides physicians with clinically useful information that will help them assist patients with known blacklegged tick bites.


Elizabeth Maloney, MD
Education Co-Director, Invisible International


Tick-borne diseases are increasingly common in many portions of the United States. Blacklegged ticks are expanding their ranges and tick bites are increasingly common. This presentation provides physicians with clinically useful information that will help them assist patients with known blacklegged tick bites.

Learning objectives

  1. Distinguish black-legged ticks from other tick species
  2. Understand facts about disease transmission
  3. Understand details regarding the use of antibiotic prophylaxis

This session, Managing Ixodes pacificus bites, is approved for 1.0 enduring AAFP Prescribed credit.

AAFP Prescribed credit is accepted by the American Medical Association as equivalent to AMA PRA Category 1 credit(s)™ toward the AMA Physician’s Recognition Award. When applying for the AMA PRA, Prescribed credit earned must be reported as Prescribed, not as Category 1.

The AAFP has reviewed One Health Medical Education for a Changing Climate and deemed it acceptable for AAFP credit. Term of approval is from 01/02/2024 to 01/01/2025. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Evidence-based bibliography for further study


• Lane RS, Quistad GB. Borreliacidal factor in the blood of the western fence lizard (Sceloporus occidentalis). J Parasitol. 1998 Feb;84(1):29-34. 

• Swei A, Ostfeld RS, Lane RS, Briggs CJ. Impact of the experimental removal of lizards on Lyme disease risk. Proc Biol Sci. 2011 Oct 7;278(1720):2970-8. doi: 10.1098. spb.2010.2402. 

• des Vignes F, Piesman J, Heffernan R, Schulze T, Stafford K, Fish D. Effect of tick removal on transmission of Borrelia burgdorferi and Ehrlichia phagocytophila by Ixodes scapularis nymphs. J Infect Dis. 2001;183:773-778. 

• Falco RC, Fish D, Piesman J. Duration of Tick Bites in a Lyme Disease-endemic Area. Am J Epidemiol 1996;143(2):187 -192. 

• Shih CM, Spielman A. Topical prophylaxis for Lyme disease after tick bite in a rodent model. J Infect Dis. 1993 Oct;168(4):1042-1045. 

• Peisman J, Schneider BS, Zeidner NS. Use of quantitative PCR to measure density of Borrelia burgdorferi in the midgut and salivary glands of feeding tick vectors. J Clin Microbiol. 2001 Nov;39(11):4145-4148. 

• Marques A, Telford SR 3rd, Turk SP, et al. Xenodiagnosis to detect Borrelia burgdorferi infection: a first-in-human study. Clin Infect Dis. 2014 Apr;58(7):937-945. 

• Frank C, Fix AD, Peña CA, Strickland GT. Mapping Lyme Disease incidence for diagnostic and preventive decisions. Emerg Infect Dis. 2002;8(4):427-429. 

• Hojgaard A, Eisen RJ, Piesman J. Transmission dynamics of Borrelia burgdorferi s.s. during the key third day of feeding by nymphal Ixodes scapularis (Acari: Ixodidae). J Med Entomol. 2008; 45(4):732-736. 

• Piesman J, Mather TN, Sinsky RJ, Spielman A. Duration of tick attachment and Borrelia burgdorferi transmission. J Clin Microbiol. 1987 Mar;25(3):557-558. 

• Eisen L. Pathogen transmission in relation to duration of attachment by Ixodes scapularis ticks. Ticks and Tick-borne Diseases 2018;9:535-542. 

• Magid D, Schwartz B, Craft J, Schwartz JS. Prevention of Lyme disease after tick bites. A cost- effectiveness analysis. N Engl J Med. 1992 Aug 20;327(8):534-541. 

• Thomas RJ, Dumler JS, Carlyon JA. Current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and Ehrlichia ewingii ehrlichiosis. Expert Rev Anti Infect Ther. 2009 Aug;7(6):709-22. doi: 10.1586/eri.09.44. 

• Pritt BS, Sloan LM, Johnson DK et al. Emergence of a new pathogenic Ehrlichia species, Wisconsin and Minnesota, 2009. N Engl J Med. 2011 Aug 4;365(5):422-429. 

• Belongia EA. Epidemiology and impact of coinfections acquired from Ixodes ticks. Vector Borne Zoonotic Dis. 2002 Winter;2(4):265-273. 

• Adelson ME, Rao RVS, Tilton RC, et al. Prevalence of Borrelia burgdorferi , Bartonella spp., Babesia microti , and Anaplasma phagocytophilum in Ixodes scapularis ticks collected in northern New Jersey . J Clin Microbio 2004; 42: 2799-2801. 

• Thompson C, Spielman A, Krause PJ. Coinfecting Deer-Associated Zoonoses: Lyme Disease, Babesiosis, and Ehrlichiosis. Clin Infect Dis 2001; 33:676-685. 

• Breitschwerdt EB, Maggi RG, Nicholson WL, Cherry NA, Woods CW. Bartonella sp. Bacteremia in Patients with Neurological and Neurocognitive Dysfunction. J Clin Microbio 2008;46(9):2856- 2861. 

• Lucey D, Dolan MJ, Moss CW, et al. Relapsing illness due to Rochalimaea henselae in immunocompetent hosts: implication for therapy and new epidemiological associations. Clin Infect Dis 1992; 14:683-688. 

• Eskow E, Rao RV, Mordechai E. Concurrent infection of the central nervous system by Borrelia burgdorferi and Bartonella henselae: evidence for a novel tick-borne disease complex. Arch Neurol 2001; 58:1357-63. 

• Birge J, Sonnesven S. Powassan Virus Encephalitis, Minnesota, USA. Emerg Infect Dis. 2012 Oct; 18(10): 1669-1671. 

• Krause PJ, Narasimhan S, Wormser GP, Rollend L, Fikrig E, Lepore T, et al. Human Borrelia miyamotoi infection in the United States. N Engl J Med. 2013;368:291-310. 

• Nadelman RB, Nowakowski J, Fish D, Falco RC, Freeman K, McKenna D et al. Prophylaxis with single-dose doxycycline for the prevention of Lyme disease after an Ixodes scapularis tick bite. N Engl J Med 2001; 345:79-84. 

• Maloney EL. The management of Ixodes scapularis bites in the upper Midwest. WMJ. 2011 Apr;110(2):78-81; quiz 85. 

• Zeidner NS, Brandt KS, Dadey E, Dolan MC, Happ C, Piesman J. Sustained-release formulation of doxycycline hyclate for prophylaxis of tick bite infection in a murine model of Lyme borreliosis. Antimicrob Agents Chemother 2004; 48:2697-2699. 

• Zeidner N, Massung R, Dolan M, Dadey E, Gabitzsch E, Dietrich G, Levin M. A sustained-release formulation of doxycycline hyclate (Atridox) prevents simultaneous infection of Anaplasma phagocytophilum and Borrelia burgdorferi transmitted by tick bite. J Med Microbio 2008; 57:463-468. 

• Knauer J, Krupka I, Fueldner C, Lehmann J, Straubinger RK. Evaluation of the preventive capacities of a topically applied azithromycin formulation against Lyme borreliosis in a murine model. J Antimicrob Chemother 2011;66(12):2814-2822. 

• Piesman J, Hojgaard A, Ullmann AJ, Dolan MC. Efficacy of an experimental azithromycin cream for prophylaxis of tick-transmitted lyme disease spirochete infection in a murine model. Antimicrob Agents Chemother. 2014;58(1):348-351. 

• Schwameis M, Kündig T, Huber G, von Bidder L, Meinel L, Weisser R. Topical azithromycin for the prevention of Lyme borreliosis: a randomised, placebo-controlled, phase 3 efficacy trial. Lancet Infect Dis. 2017 Mar;17(3):322-329. doi: 10.1016/S1473-3099(16)30529-1. 

• Wormser GP, Daniels TJ, Bittker S, Cooper D,Wang G, Pavia CS. Failure of Topical Antibiotics to Prevent Disseminated Borrelia burgdorferi Infection Following a Tick Bite in C3H/HeJ Mice. J Iinfect Dis 2012; 205:991-994. 

• Rudenko N. Golovchenko M, Grubhoffer L, et al. Updates on Borrelia burgdorferi sensu lato complex with respect to public health. Ticks Tick Borne Dis. 2011; 2(3):123-128 

• Stromdahl EY, Williamson PC, Kollars TM Jr, Evans SR, Barry RK, Vince MA, Dobbs NA. Evidence of Borrelia lonestari DNA in Amblyomma americanum (Acari: Ixodidae) removed from humans. J Clin Microbiol. 2003 Dec;41(12):5557-5562. 

• Clark K. Borrelia species in host-seeking ticks and small mammals in northern Florida. J Clin Microbiol. 2004 Nov;42(11):5076-5086. 

• Clark KL, Leydet B, Hartman S. Lyme Borreliosis in Human Patients in Florida and Georgia, USA. Int J Med Sci 2013;10(7):915-931. 

• Stromdahl EY, Nadolny RM, Gibbons JA, et al. Borrelia burgdorferi not confirmed in human- biting Amblyomma americanum ticks from the southeastern United States. J Clin Microbiol. 2015 May;53(5):1697-1704.

About Instructor

Elizabeth L. Maloney, MD

Dr. Elizabeth Maloney is a Minnesota family physician. She received her medical degree from the University of Minnesota in 1986 and completed her residency in family medicine at the University in 1989. Early in her career, she practiced in Guam, where lab and other testing modalities were often unavailable. It was here that she honed her clinical skills and learned to translate history and exam findings into clinical diagnoses and treatment plans. Dr. Maloney began reviewing the scientific literature on tick-borne diseases in earnest in 2006. Her initial review was an attempt to understand why some patients did not present or respond as described in review articles and conference lectures. When she discovered that Borrelia burgdorferi, the agent of Lyme disease, is a complex organism, the immune response to it is nuanced and there are gaps in the clinical understanding of Lyme disease, Dr. Maloney changed her focus towards educating medical professionals about tick-borne illnesses. Dr. Maloney began providing accredited continuing medical education courses on Lyme disease for physicians in 2007 and continues to do so. She has also developed similar education for nurses and mental health providers. She has published several papers in peer-reviewed medical journals and is frequently invited to speak to medical professionals across the US. She has served as a consultant to private organizations and government agencies in the US and Canada. In February 2018 she was selected to serve on the Pathogenesis, Transmission and Treatment subcommittee of the federally mandated Tick-borne Disease Working Group. Additionally, she recently accepted an invitation to serve on a peer review committee for the Canadian Institutes of Health Research.

12 Courses

Not Enrolled

Course Includes

  • 1 Lesson
  • 2 Quizzes
  • Course Certificate