Sweet Lyme Home, Chicago...

Da Bears are playin like dey got summa dat post-Lyme syndrome stuff...



Volume 13, Number 11–November 2007
Letter
Lyme Disease in Urban Areas, Chicago
Dean A. Jobe,* Jeffrey A. Nelson,† Michael D. Adam,‡ and Stephen A.
Martin, Jr.§
*Gundersen Lutheran Medical Center, La Crosse, Wisconsin, USA; †North
Park University, Chicago, Illinois, USA; ‡Lake County Department of
Public Health, Waukegan, Illinois, USA; and §Cook County Department of
Public Health, Oak Park, Illinois, USA

Suggested citation for this article

To the Editor: Lyme disease is a multisystem illness caused by
infection with the tickborne spirochete Borrelia burgdorferi. Most
infections in the United States occur in the Northeast and upper
Midwest, and the midwestern focus now includes Illinois (1,2).
Previously, the greatest risk of contracting Lyme disease in the
Midwest was confined to the northernmost states (Wisconsin and
Minnesota) and did not encroach into heavily populated areas around
the city of Chicago. However, we showed recently that B. burgdorferi–
infected Ixodes scapularis ticks were recovered from sites in Cook and
DuPage counties (3), but the percentages of infected ticks were low
(<5%). Since that time, however, reports of Lyme disease in Cook
County have been reviewed and individual I. scapularis tick
submissions from Lake County, north of Chicago, have been received. We
therefore surveyed new areas north of Chicago (closest was <1 mile
from the city limits; farthest was ≈25 miles from the city limits) and
examined additional ticks for infection with B. burgdorferi.


From December 2006 to May 2007, we collected 172 adult I. scapularis
ticks from sites to the north and northwest of Chicago (Figure). Adult
ticks were collected because nymphal ticks are more difficult to
obtain, and the infection rate in adult ticks is similar (1). The tick
midguts were removed aseptically, inoculated into tubes containing 1
mL of modified Barbour-Stoenner-Kelly medium (4), incubated at 35°C,
and examined for spirochetes for up to 3 weeks. Spirochetes were
recovered from 21 (32%) of 65 ticks and 40 (37%) of 107 ticks
collected from sites in Cook and Lake counties, respectively. In
addition, PCR using primers specific for outer surface protein A (5)
confirmed that the spirochetes were B. burgdorferi.

The findings demonstrate that the midwestern endemic focus of B.
burgdorferi–infected I. scapularis now includes northern Cook and Lake
counties. More importantly, the high percentage of B. burgdorferi–
infected ticks in this region confirms a newly recognized significant
risk of Lyme disease in suburban areas adjacent to Chicago (population
≈7 million). Recently, the Infectious Diseases Society of America
recommended that clinicians consider prescribing a single prophylactic
dose of doxycycline (200 mg) when patients have received tick bites in
areas where the percentage of B. burgdorferi–infected I. scapularis
exceeds 20% (6,7). The high percentage of infected adult ticks
identified in this survey highlights the need for physicians in the
Chicago area to become familiar with this recommendation, especially
considering the high likelihood that nymphal I. scapularis ticks are
similarly infected (1). Moreover, confirmation of the increasing risk
of contracting Lyme disease near metropolitan Chicago should provide
impetus for more comprehensive studies to completely define the risk
of this potentially serious illness.

Acknowledgments
We thank Joan Bestu*** and Linn Haramis for initiating the studies;
Joshua J. Nelson, K. Adam Nelson, Mark Hurley, and the North Park
University parasitology class for tick collections; Steven Callister
and Steven Lovrich for laboratory assistance; and Maria Vastis for
secretarial support.

References
Nelson JA, Bouseman JK, Kitron U, Callister SM, Harrison B, Bankowski
MJ, et al. Isolation and characterization of Borrelia burgdorferi from
Illinois Ixodes dammini. J Clin Microbiol. 1991;29:1732–4.
Callister SM, Nelson JA, Schell RF, Jobe DA, Bautz R, Agger WA, et al.
Survey for Ixodes spp. and Borrelia burgdorferi in southeastern
Wisconsin and northeastern Illinois. J Clin Microbiol. 1991;29:403–6.
Jobe DA, Lovrich SD, Nelson JA, Velat TC, Anchor C, Koeune T, et al.
Borrelia burgdorferi in Ixodes scapularis ticks, Chicago area. Emerg
Infect Dis. 2006;12:1039–41.
Callister SM, Case KL, Agger WA, Schell RF, Johnson RC, Ellingson JLE.
Effects of bovine serum albumin on the ability of Barbour-Stoener-
Kelly medium to detect Borrelia burgdorferi. J Clin Microbiol.
1990;28:363–5.
Nocton JJ, Dressler F, Rutledge BJ, Rys PN, Persing DH, Steere AC.
Detection of Borrelia burgdorferi DNA by polymerase chain reaction in
synovial fluid from patients with Lyme arthritis. N Engl J Med.
1994;330:229–34.
Wormser GP, Dattwyler RJ, Shapiro ED, Halperin JJ, Steere AC, Klempner
MS, et al. The clinical assessment, treatment, and prevention of Lyme
disease, human granulocytic anaplasmosis, and babesiosis: clinical
practice guidelines by the Infectious Diseases Society of America.
Clin Infect Dis. 2006;43:1089–134.
Nadelman RB, Nowakowski J, Fish D, Falco RC, Freeman K, Mc Kenna D, et
al. Prophylaxis with single-dose doxycycline for the prevention of
Lyme disease after Ixodes scapularis tick bite. N Engl J Med.
2001;345:79–84.
Figure
Figure. Sites surrounding Chicago from which Borrelia burgdorferi–
infected Ixodes scapularis ticks were recovered in 2005–2006 (n) and
2006–2007 (l).

Suggested Citation for this Article
Jobe DA, Nelson JA, Adam MD, Martin SA. Lyme disease in urban areas,
Chicago [letter]. Emerg Infect Dis. [serial on the Internet]. 2007 Nov
[date cited]. Available from http://www.cdc.gov/EID/content/13/11/1799.htm

.

Quantcast