Determining the Location and
Seasonality of Clinically Important
Tick Species in Maryland
Sean M. Bialosuknia
PHASE Symposium, 2013
Preceptors
• Maryland Department of Health and Mental
Hygiene
– Center for Zoonotic and Vector Borne Disease
Erin Jones, MS – Epidemiologist
Katherine Feldman, DVM, MPH—State Public Health
Veterinarian
Clinically Important Tick Species in Maryland
Disease
Pathogen
Babesiosis
Babesia microti
Lyme disease
Borrelia burgdorferi
Anaplasmosis
Anaplasma
phagocytophilum
Ehrlichiosis
Ehrlichia chaffeensis,
Ehrlichia ewingii
Rocky Mountain
spotted fever (RMSF)
Rickettsia rickettsii
Tularemia
Francisella tularensis
Tick Vector
Ixodes scapularis
(Black-legged tick)
Amblyomma
americanum
(Lone star tick)
Dermacentor
variabilis
(Dog tick)
Background
• Seasonality and life stage is important to consider
in each species of tick
– A. americanum can feed on humans at any stage of its
life cycle, and is most active in late spring through
summer
– D. variabilis only feeds on humans in its adult form,
and is active in late spring through summer
– I. scapularis can feed on humans as a nymph and as an
adult. Nymphs seek bloodmeals in the spring, and
adults seek bloodmeals in the fall
• No formal tick surveillance system in Maryland
Maryland Department of Agriculture
Tick Identification Service (MDATIS)
• Passive surveillance, convenience sample
• Started in late 1990s, has been continuous
though 2012
• Can be submitted year round
• Submitter notified of the tick species
• The submission form has a user-completed
portion which is used to determine the
geographic location where the tick was
collected.
Purpose
• To expand the understanding of the
geographic distribution and seasonal
abundance of ticks that humans are likely to
encounter in Maryland
– Characterize data submitted through the MDATIS
– Tick submissions data will be compared to a
literature search for documented tick location
Methods
• Entered 2012 data into the MS Access
database
• Analyzed MDATIS records from 2005 – 2012
• Determination of county of collection from
the (MDATIS) records
• Literature search
Results
• 1027 submissions from 2005 through 2012
– 17 (2%) ticks submitted not from the species studied
– 47 (5%) non-tick submissions
• 916 tick submissions
– 583 (64%) A. americanum
– 165 (18%) D. variabilis
– 213 (23%) I. scapularis
MDATIS tick submissions by year of collection
(2005-2012)
250
MDATIS Tick Submissions
Amblyomma americanum
200
Dermacentor variabilis
Ixodes scapularis
150
Total Submissions
100
50
0
2005
2006
2007
2008
2009
2010
2011
2012
A. americanum by year of collection (2005-2012)
80
Amblyomma americanum Adult
MDATIS Tick Submissions
70
Amblyomma americanum Nymph
60
Amblyomma americanum Larvae
50
Amblyomma americanum Unknown
40
30
20
10
0
2005
2006
2007
2008
2009
2010
2011
2012
D. variabilis by year of collection
70
Dermacentor
variabilis Adult
MDATIS Tick Submissions
60
Dermacentor
variabilis Nymph
50
Dermacentor
variabilis Larvae
40
Dermacentor
variabilis Unknown
30
20
10
0
2005
2006
2007
2008
2009
2010
2011
2012
I. scapularis by year of collection
30
Ixodes scapularis Adult
MDATIS Tick Submissions
25
Ixodes scapularis Nymph
Ixodes scapularis Larvae
20
Ixodes scapularis Unknown
15
10
5
0
2005
2006
2007
2008
2009
2010
2011
2012
Total I. scapularis submissions by month (2005-2012)
MDATIS Tick Submissions
45
40
2012
35
2010
30
2009
25
2007
20
15
10
5
0
2011
2008
2006
2005
Results
• 160 ticks of indeterminable geographic location
omitted
• 756 tick submissions used in my analysis
– 429 (57%) A. americanum
– 146 (19%) D. variabilis
– 181 (24%) I. scapularis
MDATIS Tick Submissions
County of
A. americ. D. variab.
Collection
Allegany
Anne Arundel
Baltimore
Baltimore City
Calvert
Caroline
Carrol
Cecil
Charles
Dorchester
Frederick
Garret
Harford
Howard
Kent
Montgomery
Prince George's
Queen Anne's
Somerset
St. Mary's
Talbot
Washington
Wicomico
Worcester
Found in literature
Total Ticks
Submitted
I. scap.
1
179
1
19
1
44
3
242
3
0
15
7
2
4
18
13
8
7
0
10
0
2
0
1
0
0
6
0
15
10
7
2
8
3
2
0
6
0
2
2
0
3
1
33
35
0
0
0
5
1
31
29
1
10
3
10
2
70
64
3
11
6
12
29
86
13
12
9
2
2
0
0
0
24
29
0
20
1
1
2
0
2
2
3
0
0
27
32
5
20
11
1
0
12
111
13
A. americ. D. variab.
Xxii
I. scap.
Xxii
Xxii
Xxiii
Xxiii
Xxii
Xxii
Xxii
Xxiv
Xxiv
Xxiv
Xxii
Xxii
Xxii
Xxiv
Xxv
Xxiv
Xxii
Xxii
Xxii
Xxii
Xxii
Xxii
Xxv
Xxii
Xxii
Xxii
Xxv
Xxv
Xxv
Anderson, Jennifer M. et al. (2006). Mammal diversity and infection prevalence in the maintenance of enzootic Borrelia burgdorferi along the western coastal plains of Maryla
XIII Hofmeister, Erik K. et al. (1999). Longitudinal study of infection with Borellia burgdorferi in a population of Peromyscus leucopus at a lyme disease-enzoonotic site in Marland.
XIV Schmidtmann, E. T. et al. (1994). Host-seeking of blacklegged tick (acari: Ixodidae) nymphs and adults at the woods-pasture interface. Journal of Medical Entomology, 31(2), 2
XIV Swanson Katherine I, & Norris, D. E. (2007). Co-circulating microorganisms in questing Ixodes scapularis nymphs in Maryland. Journal of Vector Ecology, 32(233-51).
XII
A. americanum found in literature
A. americanum found in literature
No A. americanum found in literature
A. americanum submitted to MDATIS
A. americanum submitted
No A. americanum submitted
I. scapularis found in literature
I. scapularis found in literature
No I. scapularis found in literature
I. scapularis submitted through
MDATIS
I. scapularis submitted
No I. scapularis submitted
Limitations & Suggestions
• Tick identification service is a convenience
sample, dependent on the public awareness
of the service
– Better advertising would help boost public
awareness of the program
• Quality of data from user submitted form,
errors associated with this type of data
– Suggest modification of submission form “County
of collection” field
Policy and Practice Implications
• Additional advertising for the MDATIS would allow for
more counties with high tick prevalence to be
identified
– Counties that have particularly high numbers of
submissions can be targeted for primary prevention
campaigns
• Continued collaboration between the PHASE program,
the Maryland DHMH, and the Maryland Department of
Agriculture
– Supplies an intern to the DHMH to work on projects that
need attention, protected time
– Helps intern complete requirements for the masters
program
References
Magnarelli, L. Global Importance of Ticks and Associated Infectious Disease Agents. Clinical Microbiology Newsletter. 2009;31:33-37.
Feldman, KA. Tickborne Diseases in Maryland. Center for Zoonotic and Vector Borne Diseases. Maryland Department of Health and Mental Hygiene, Baltimore Maryland. November 15, 2012.
Centers for Disease Control and Prevention. Reported Cases of Lyme Disease by state or locality, 2002-2011. [Internet] 2012 Oct [cited 2013 Apr 15]. Available from:
http://www.cdc.gov/lyme/stats/chartstables/reportedcases_statelocality.html.
Bacon, R. M., Kugeler, K. J., Mead, P. S. Surveillance for Lyme Disease --- 1994—2006. Retrieved November 15, 2012, from the Centers for Disease Control and Prevention, Morbidity and Mortality
Weekly Report [Internet]. 2008, October 3 [cited April 15, 2013]. Available from (http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5710a1.htm).
Heilpern, K. Human Erlichiosis--Maryland and Wisconsin. Annals of Emergency Medicine, 1998;39:109-110.
Childs, J. E., & Paddock, C. D. The ascendancy of Amblyomma americanum as a vector of pathogens affecting humans in the United States. Annual Review of Entomology, 2003;48:307-37.
Centers for Disease Control and Prevention. Tularemia--United States, 1990-2000. MMWR, 2002;51(9):182-4.
Stafford, K. C. Ticks. The Connecticut Agricultural Experiment Station [Internet]. 2001, April [cited April 15, 2013]. Available from
(http://www.ct.gov/caes/lib/caes/documents/publications/fact_sheets/ticks.pdf).
Chan, WH. Kaufman, PE. Featured Creatures: The American Dog Tick (Dermacentor variabilis). University of Florida Food and Agricultural Science Department. [Internet]. January 2013. [cited April
15, 2013]. Available from (http://entnemdept.ufl.edu/creatures/urban/medical/american_dog_tick.htm).
Stafford, K. C. Tick Management Handbook. The Connecticut Agricultural Experiment Station. [Internet] Fall 2007. [cited November 15, 2012]. Available from
(http://www.ct.gov/caes/lib/caes/documents/publications)
Tickmap. [Internet] November 26, 2012. [cited April 10, 2013]. Available from http://www.tickmap.org/
Anderson, Jennifer M. et al. Mammal diversity and infection prevalence in the maintenance of enzootic Borrelia burgdorferi along the western coastal plains of Maryland. Vector-Borne and
Zoonotic Disease.2006;6(4):411-22.
Hofmeister, Erik K. et al. Longitudinal study of infection with Borellia burgdorferi in a population of Peromyscus leucopus at a lyme disease-enzoonotic site in Marland. American Journal of
Tropical Medicine, 1999:60(4);598-609.
Schmidtmann, E. T. et al. Host-seeking of blacklegged tick (acari: Ixodidae) nymphs and adults at the woods-pasture interface. Journal of Medical Entomology,1994:31(2);291-96.
Swanson Katherine I, & Norris, D. E. (2007). Co-circulating microorganisms in questing Ixodes scapularis nymphs in Maryland. Journal of Vector Ecology,2007:32;233-51