THE TROUBLE WITH TICKSTHE TROUBLE WITH TICKS

Protecting Forest Service EmployeesWorking In The Pacific Northwest

From Lyme Disease

Prepared by: James Reim: Siuslaw Nat’l Forest and Corvallis Forestry Sciences Lab

Dan Hollars: Fremont National Forest

May, 2000

The Story The Story

Ticks sometimes transmit Lyme Disease, a potentially debilitating disease.

People who work or recreate outdoors could be infected when the disease is present and they don’t take a few simple proper protective measures.

Supervisors must make sure that their field-going employees understand the nature of the hazard, and that they protect themselves.

The Subplots:The Subplots:

The nature of Lyme disease.Life cycle and behavior of ticks.At risk behaviors of people.Steps in preventing infection.Signs of infection.Getting medical attention.Prevention through vaccination.Summary

Employee

Doctor

Environment

Borrelia

burgdorferi

Ticks

Preferred Hosts

Supervisor

The The CharactersCharacters

Borrelia burgdorferi, the bacterium that causes Lyme disease, is the central character; but it doesn’t work alone. The roles of all the players must be understood, to ensure employees are protected.

The Plot ChoicesThe Plot Choices

Tick ingests blood from an infected host.

Tick attaches itself to an unprotected employee.

Employee gets infected, and without early treatment,…

Employee gets really sick.

Supervisor makes sure employee understands the hazard, and how to protect him/herself.

Tick ingests blood from an infected host.

Employee protects her/him self, and...

Employee stays healthy.

(or)

Lyme DiseaseLyme Disease

Lyme disease is an infection caused by a bacterium (Borrelia burgdorferi) that is carried in the east and mid-west by the deer tick, and in the west by the Western black-legged tick.

Lyme disease causes inflammation. In early stages, it causes a skin rash, and sometimes joint pain, chills, fever and fatigue. As it progresses, it affects joints and the nervous system.

During early stages of infection, Lyme disease can be successfully treated with antibiotics.

If untreated during the early stages, Lyme disease can cause serious and sometimes disabling disorders.

Distribution of Lyme Disease In The Distribution of Lyme Disease In The United States:United States:

1998 Reported Lyme Disease Cases

Per 100,000 Population(Incidence Rate)

                                                                                                       

            

Geographical Distribution ofReported Lyme Disease Cases

(1998)

After it hatches from the egg, a tick After it hatches from the egg, a tick undergoes 3 growth stages, during a two undergoes 3 growth stages, during a two year period:year period:

1. Eggs laid in spring hatch in the Summer.2. Larvae (the size of a newsprint period) lie on the ground, waiting for a host to

brush against them.3. After a blood meal, the larvae drop off and molt into nymphs during the Fall. 4. Nymphs (the size of a poppy seed) become active in the Spring and attach

themselves to another host. After a blood meal, they drop into the leaf litter and molt into adults.

5. Adults (the size of a sesame seed) climb onto edges of grass or leaf tips in the Fall, and wait for their next host. After feeding for about a week, adults mate.

6. Adults who don’t get their blood meal by the time cold weather arrives go into a dormant stage during the Winter. When temperatures get above 40 degrees, they again look for a host.

7. In the spring, females lay approximately 3,000 eggs under the leaf litte--------------------1. The eggs hatch in the summer and the cycle continues…

Tick Life Stages, Ambush SitesTick Life Stages, Ambush Sitesand sizes relative to the eye of a needleand sizes relative to the eye of a needle

(a needle’s eye)

The nymph waitson the ground, in leafLitter, or on leavesof grass.

The adult waits on grass, or leaf edges,Within 3 feet of theground

The larva waits in the Leaf litter. (Note: The larva isNot infected with BoreliaBugdorferi when it Hatches, therefore it doesNot infect its host.)

Life Life Cycle Cycle of a of a Tick:Tick:

                                                                       

                

Note:Ticks may be active in the winter when temperatures are over 40 degrees.

Transmission of Lyme disease:Transmission of Lyme disease:

Tick larvae are not infected when they are born, and will not transmit the disease..

Larvae and nymphs become infected when they feed on an infected host.

Nymphs and adults can infect hosts if the larva or nymph became infected during its previous life stage.

(Studies indicate that if an infected nymph feeds on some species of lizard, the bacteria are killed, and the tick will not transmit the disease when it is in the adult stage.)

Tick food and habitat preferences:Tick food and habitat preferences: Larvae and nymphs prefer small mammals, birds, and lizards, but are willing

to feed on larger animals, including humans and Forest Service employees. Adults prefer to feed on deer, but are willing to substitute other larger

mammals, including humans and Forest Service employees. Nymphs live in leaf mold and on the ground.. Nymphs wait on the ground or on the edges of grass leaves. Adults wait on grass or leaves of other vegetation within 3 feet of the ground. When a host brushes by, the tick climbs on the host and looks for a place to

attach itself. Once it attaches itself, the tick will feed for several days to a week. After it is

engorged, it drops off. Larvae and nymphs then wait for the next life stage before they feed again.

Adult females develop and lay their eggs, and die. Adult males die.

The Business End Of A Tick:The Business End Of A Tick:

Enlarged View of Tick Mouthparts

Tick Perched On A Blade of Grass,…Waiting For A Host To Brush Past

Tick larvae on ears of a host:Tick larvae on ears of a host:

                 

At-risk occupations and At-risk occupations and Employer responsibilities:Employer responsibilities: The Centers for Disease Control and Prevention has determined

that Lyme disease is endemic in California and Oregon. Any occupation that requires outdoor work in an area where

Lyme disease is endemic is considered at risk of becoming infected.

Employees working in wildland environments in the Pacific Northwest may be exposed to ticks carrying Lyme disease.

These employees must understand the nature of Lyme disease, how they might be infected, and how they can protect themselves.

Employers must provide means for employees to protect themselves, and to get medical attention if exposed to the disease.

Preventing infection:Preventing infection:To prevent exposure to infection, people whose work requires

them to be in forested, brushy, or grassy areas should do the following to protect themselves from being bitten by ticks:

1. Assume that ticks which are infested with Borrelia bugdorferi may be present.

2. Dress in a manner that prevents ticks from getting on their skin, and that allows them to easily see ticks on the clothing (i.e. light-colored clothing).

3. Watch throughout the day for ticks on their clothing and skin, and remove them immediately.

4. Avoid placing jackets and other clothing on the ground.5. Check for presence of ticks on their body at the end of the day, and

carefully remove them if they occur.

Protective clothing:Protective clothing:

Wear boots, light-colored pants, and light-colored long-sleeved shirts. Tuck pants into socks and shirts into pants.

Keep long hair gathered up or tied back, and covered. Use insect repellant containing DEET on exposed

skin. (Follow manufacturer’s directions.) Apply DEET or Permethrin (an insecticide) on

clothing. (Follow manufacturer’s directions. Do not use Permethrin on skin.)

Protective Behaviors:Protective Behaviors:

Stay out of grass and brush until properly dressed.

Check clothing frequently to spot ticks, and brush them off. (Note: When clothing effectively keeps ticks off the skin, they will climb upwards, looking for access to the skin.)

Complete a full-body “tick check” at the end of the day. Remove ticks that have not attached themselves. If ticks are attached, get assistance to remove them without squeezing or breaking them. (Note: Studies indicate that ticks normally infect a host only after they have been feeding for 36 to 48 hours.)

“tick-checking”

                 

Removing a tick:Removing a tick:

Use a specially designed tick removal tool, or fine pointed precision tweezers.

Grasp the head or mouth. Gently and firmly pull outward.

Clean the bite wound with disinfectant.

Get medical assistance to remove ticks if they are difficult to access, if you do not have the proper tool, or if you are not confident you can do it properly.

Save the tick to assist in diagnosis if problems develop.

Grasp the tick by the body. Twist the tick. Apply oil, petroleum jelly,

alcohol, heat, or other irritants.

Try removing ticks without proper tools.

Try to remove ticks that are difficult for you to see or reach.

DO: DO NOT:

(Be gentle. Be Firm. Be nice…and get it off in one piece!)

The most common early symptom of The most common early symptom of Lyme disease is an expanding rash:Lyme disease is an expanding rash: A rash occurs in 80-90% of infections. The rash is solid red or a series of red rings. It expands to

a diameter ranging from 2 inches to 2 feet. On dark-skinned people, the rash may look like a dark bruise.

The rash appears 3-30 days after infection occurs, …and lasts for 3-5 weeks.

The rash is usually not painful or itchy. Other symptoms which may occur around the time the

rash occurs are: swelling of lymph glands, headache, joint pains, chills, fever, and fatigue. These symptoms may be intermittent and mild.

Characteristic rash associated with Lyme Characteristic rash associated with Lyme disease:disease:

Lyme disease is easily treated with Lyme disease is easily treated with antibiotics, and almost always cured, antibiotics, and almost always cured, when it is treated during the early when it is treated during the early stages of infectionstages of infection..

Treatment within the first 3 weeks of infection is straightforward and almost always successful.

The cure rate decreases the longer treatment is delayed. Generally, Lyme disease can also be effectively treated

in its later stages, but symptoms may linger for months or years following treatment.

In rare instances, Lyme disease causes permanent damage.

Severe, potentially debilitating Severe, potentially debilitating symptoms can occur weeks, symptoms can occur weeks, months, or even years after being months, or even years after being bitten by an infected tick:bitten by an infected tick:

Severe headachesPainful arthritisCardiac abnormalitiesCognitive (mental) disorders

Getting treatment for Lyme diseaseGetting treatment for Lyme disease Get medical assistance in removing ticks that are attached and are

not easy to access or remove. See a physician immediately if, in the process of removing a tick,

the body was squeezed or the mouth parts were broken. Take the tick along.

See a physician immediately if a tick has attached itself on your body long enough to engorge and enlarge.

See a physician immediately if an expanding rash occurs near a tick bite.

See a physician if joint pains, chills, fever, or fatigue occur after incurring a tick bite.

Diagnosis can be complicated. Choose a physician who understands current methods of diagnosing and treating Lyme disease.

Reporting tick bites is important in Reporting tick bites is important in getting proper medical treatment if getting proper medical treatment if problems occur.problems occur. If a tick bite occurs, employees should fill out a CA-1

form, and give it to their supervisor within 24 hours. If a tick is attached, and the employee has difficulty

removing it, or is uncomfortable removing it, she/he should get authorization for medical treatment from her/his supervisor.

If the supervisor or acting is not available, get treatment then tell supervisor as soon as possible.

Employees who work outdoors in western Oregon, and Employees who work outdoors in western Oregon, and other areas where there is a chance of contracting other areas where there is a chance of contracting Lyme disease, have the right to be vaccinated.Lyme disease, have the right to be vaccinated.

The vaccine is given in a series of 3 shots. The second shot occurs at 1 month, and the third at 6-12 months after the initial shot.

Costs of the vaccination will be covered by the budget of the project which requires the employees to work in potentially tick-infested areas.

Studies indicate that the vaccine is 80% effective after all 3 shots, and 50% effective after 2 shots.

Effectiveness of the vaccine beyond 2 years is unknown. Undesirable side effects of the vaccine may occur. The vaccine may not be effective in providing immunity for all strains of

Lyme disease. The vaccine is not effective in providing immunity for other major diseases

which ticks may carry. Employees should consult with their physician to determine if the vaccine is

appropriate for them, and whether they want to request the vaccination series.

SummarySummary Employees working outdoors in the Pacific Northwest may be exposed to ticks that

could transmit Lyme disease and other diseases. These employees should dress in a manner that prevents ticks from attaching to their

skin and allows the employee to easily see ticks on their clothing Employees working in the field should check their bodies for presence of ticks at the

end of the day. These employees should know how to recognize and remove ticks, and should

understand symptoms of infection. Employees should report all tick bites to their supervisor. Employees should get medical treatment if:

– they have difficulty removing a tick; – if the tick is damaged or squeezed during removal; or, – if they experience symptoms of Lyme disease infection.

Employees should understand that a Lyme disease vaccination is available to them at no cost to the employee, but vaccination is not a substitute for preventing exposure to tick bites.

Additional, periodically updated, information about Lyme Additional, periodically updated, information about Lyme disease is available on the internet from organizations such as disease is available on the internet from organizations such as the American Lyme Disease Foundation, Inc., the American Lyme Disease Foundation, Inc., www.www.aldfaldf.com.com, ,

and The Lyme Disease Network of NJ, Inc., and The Lyme Disease Network of NJ, Inc., www.lymenet.org/www.lymenet.org/

Information is also available from The Centers For Disease Information is also available from The Centers For Disease Control, The Occupational Safety and Health Administration, Control, The Occupational Safety and Health Administration,

and local public health agenciesand local public health agencies

Forest Service policy regarding protection from Lyme disease Forest Service policy regarding protection from Lyme disease and other diseases transmitted by ticks is available in FSH and other diseases transmitted by ticks is available in FSH

6709.11, section 53.26709.11, section 53.2