Ticks and Tick Bornes Illnesses in Ohio

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Tick-borne DiseasesOhio Summary, 2010Zoonoc Disease Program Bureau of Infecous Diseases

Ohio Department of Health

Background

During 2010, there were 848 cks submied to the Ohio Department of Health (ODH) (Table 1).

This report addresses the three species of greatest public health importance because they are

known to transmit diseases to humans. The American dog ck and the lone star ck are among

the most commonly encountered cks in

Ohio. The third ck, the black-legged ck

or deer ck was once considered quite rare

in Ohio. Recent increases in submissions

to the ODH Vector-borne Disease Labora-

tory suggest that this ck is becoming more

common in the state. All of these cks are

acve in Ohio from early spring unl late

autumn and, in the case of the black-legged

ck, on warm days during the winter. In

2010, 78 people were confirmed with a

ck-borne disease in Ohio (Appendix A).

People working and playing outdoors in

wooded or weedy areas may be exposed tocks and possibly ck-borne diseases such

as Rocky Mountain spoed fever (RMSF),

Lyme disease and ehrlichiosis. Not all ck species carry and transmit every disease, so it is im-

portant to idenfy cks to beer esmate disease risk.

Rocky Mountain Spotted Fever

In 2010, Ohio reported 15 human cases of RMSF in the state. While RMSF is endemic

throughout Ohio, almost half of all human cases have been reported from three counes; Cl-

ermont, Franklin and Lucas. From 2000-2010, there were 174 cases and one death from Ohioreported to the Centers for Disease Control and Prevenon (CDC).

RMSF is caused by the bacterium, Rickesia rickesia. Larval and nymphal cks become in-

fected with R. rickesiiwhile feeding on blood from an infected host and a female ck can

transmit R. rickesiito her eggs through a process called transovarial transmission. Once in-

fected, the ck can carry the pathogen for life. The bacteria are transmied through ck saliva

while feeding. It usually takes several hours of aachment and feeding for the bacteria to be

transferred to the host. Only one to three percent of the ck populaon carries R. rickesii

Table 1: Ticks submied to the ODH Vector-borne Laboratory for

idenficaon in 2010

Species of Tick Number Idenfied

Amblyomma americanum 90

Carios kelleyi 2

Dermacentor albipictus 41

Dermacentor variabilis 586

Haemaphysalis leporispalustris 2

Ixodes cookei 70

Ixodes dentatus 2

Ixodes scapularis 47

Ixodes sp. 7

Rhipicephalus sanguineus 1

Grand Total 848


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(even in areas where the majority of human cases are reported); so risk of exposure to an in-

fected ck is low.

Symptoms of RMSF

The incubaon period for RMSF is two to 14 days aer ck bite or contact. Symptoms include

a sudden onset of fever, headache and flu-like symptoms, oen followed by the characteriscspoed rash. The rash first appears at the wrists and ankles and may spread to the torso, palms

and soles. If not treated with anbiocs, the disease has a fatality rate of four percent.

Vector of RMSF

The American dog ck, Dermacentor variabilis (Figure

1), is the primary vector of RMSF in the eastern United

States (Figure 1). In Ohio, thisck is widespread and

abundant. The American dog ck is most acve from

April through July. This ck will bite and feed on anyavailable mammal, including humans.

Lyme Disease

Lyme is a bacterial disease caused by Borrelia burgdor-

feri, a spirochete-type bacterium. Lyme disease is highly

endemic in the Northeast and Upper Midwest and is the

most commonly reported vector-borne disease in the United States. About 20,000 cases are re-

ported to CDC each year. Ohio is located between these two endemic regions and has reported a

fairly low incidence of Lyme disease in the past. The low number of Lyme cases in Ohio is arib-uted to the absence ofIxodes scapularis (Figure 2), the vector transming Borrelia burgdorferi.

In 2010, Ohio reported 43 cases of Lyme disease to the CDC. Since 1990, Ohio has reported

1,035 cases of Lyme disease from 83 of 88 counes. Data from this period show that about half

of Ohios cases of Lyme disease had no travel history. This means people acquired Lyme disease

in Ohio, despite the fact that the ck responsible for the disease is rarely found here. The ODH

will connue surveillance for this disease and its vector in addion to educang Ohio residents

about disease prevenon.

Symptoms of Lyme Disease

The first sign of a Lyme disease infecon, seen in 60 to 80 percent of cases, is the characterisc

bulls-eye rash called erythema migrans. The rash develops at the site ofck aachment and

usually appears seven to 14 days aer ck exposure. Other symptoms may include muscle aches,

general redness, fever, swollen glands, headache and joint pain.

Vector of Lyme Disease

In the eastern United States, Lyme disease is transmied by the black-legged ck, Ixodes scapu-

laris, also known as the deer ck (Figure 2). The nymphal cks are acve in late spring and

Figure 1. American Dog Tick, Dermacentor variabilis.


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summer when human populaons are outdoors and likely to be exposed. These cks are found in

areas of deciduous forest, especially those with a leaf lier habitat on the ground. The leaf lier

provides protecon from the elements and when re-

moved, ck populaons may be reduced by 70 to 100

percent.

This ck was considered rare in Ohio, with a total of50 cks submied from within the state during the 20

year period of 1989-2009. However, there has been a

steady increase in submissions recently with 40 cks

idenfied from Ohio in 2010 (Figure 3).

In addion, alerted by an increasing number of black-

legged cks submied by residents in Coshocton

County, a group of invesgators from The Ohio State

University (OSU) and ODH launched a concerted effort to assess the risk of Lyme disease within

that county. In 2010, over 300 black-legged cks represenng all life stages were captured and

tested. Of those, 67 tested posive for the

agent of Lyme disease. Infecon rates in the

cks increased during the summer and fall.

In addion, two of 10 white-footed mice (the

Lyme disease reservoir) from an area with

known black-legged cks tested posive for

Lyme disease (personal communicaon, Glen

Needham, PhD, Associate Professor OSU).

This is the first evidence that there is now anestablished populaon of black-legged cks

in Ohio and that the agent of Lyme disease is

established in the local ecosystem. Research

into the possible range of this ck in Ohio will

connue in 2011.

Ehrlichiosis and Anaplasmosis

Ehrlichiosis and anaplasmosis are ck-borne

diseases caused by several species of bacteria.These bacteria are transmied through the

bite of a ck and may also cause disease in humans and animals such as dogs, cale, sheep and

horses. There were eight cases of ehrlichiosis and two cases of anaplasmosis confirmed in Ohio in

2010.

Symptoms of Ehrlichiosis and Anaplasmosis

The bacteria that cause ehrlichiosis and anaplasmosis are different, but their symptoms are similar

and may be confused with common infecons such as influenza. For ehrlichiosis, disease onset

Figure 3. Ixodes scapulariscks from Ohio submied to ODH,

2010. N=40

Figure 2. Black legged Tick, Ixodes scapularis.


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Prevention

Avoiding exposure to cks is the best way to prevent ck-borne diseases such as Lyme disease and

RMSF. Ticks prefer tall grass and brushy areas with leaf lier, so avoid those areas whenever pos-

sible. When hiking, stay in the middle of the trail as high grass on the edges of paths is a perfect

ck habitat. Keep grassy, outdoor play areas and yards well mowed to discourage ck infestaons.

When going into areas where cks may be present:

Tuck your pants into your socks to keep the cks away from your skin

Wear light colored clothing. This will make it easier to find crawling cks

Use repellents such as 20 percent DEET and follow label instrucons carefully

Check for cks frequently, especially on children

Shower within two hours of coming indoors to prevent cks from aaching

Remove any aached cks promptly and carefully

Protect Your PetsDogs can develop ck-borne diseases as well. In addion,

they can bring cks home with them. During ck season (April

to August) dogs should be kept or walked in well-mowed areas

whenever possible. Inspect dogs for cks every day (Figure

5) and if any are found, remove them promptly and carefully.

There are many good ck control products for dogs. Talk to

your veterinarian about recommendaons and always follow

product instrucons, as some products might be toxic if used

incorrectly. If your pet becomes ill, have your pet examined by

a veterinarian and tell them about any recent ck exposure.

More Information

For more informaon on cks and ck borne diseases, con-

tact your local health department. For a list of health departments, visit hp://www.odh.ohio.gov

and click on Local Health Departments.

Addional sources of Informaon on ck borne diseases can be found at:

Infecous Disease Control Manual, Ohio Department of Health (select disease of interest)

hp://www.odh.ohio.gov/pdf/IDCM/sect3TOC.pdf

Tick-borne Diseases, Ohio Department of Health

hp://www.odh.ohio.gov/odhPrograms/dis/zoonoses/vbdp/vbck.aspx

Tick-borne Diseases in the U.S., Centers for Disease Control and Prevenon

hp://www.cdc.gov/cks/diseases/

Tick-borne diseases in animals, Center for Food Safety & Public Health, Iowa State University

hp://www.cfsph.iastate.edu/DiseaseInfo/

Figure 5. The ear of dogs is a likely place

to find cks.


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Appendix A

Human cases of Reportable Tick-borne Diseases in Ohio, 2010

*http://www.cdc.gov/osels/ph_surveillance/nndss/casedef/case_definitions.htm

Rocky Mountain Spotted Fever

Total: 15

Counties: 12

Lyme disease

Total : 43

Counties : 24

Ehrlichiosis (E)

Total: 8Counties: 4

Anaplasmosis (A)

Total: 2

Counties: 2

Includes cases that meet the Centers for Disease Control and Prevention

case definition as confirmed or probable*
http://www.cdc.gov/osels/ph_surveillance/nndss/casedef/case_definitions.htmhttp://www.cdc.gov/osels/ph_surveillance/nndss/casedef/case_definitions.htm

Ticks and Tick Bornes Illnesses in Ohio

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