1. Lyme on the rise
The black legged tick

2. The Increase of Lyme in Minnesota
A local family physician inquires about Lyme disease noting an increase of patients experiencing:
ring shaped rashes
headaches
fever chills
Rigid diagnosis was not made as confirmation requires time that a patient may not have.

3. High Risk Areas for Tick-borne Diseases in Minnesota
The physician expressed concern that the map by Minnesota Department of Natural Resources may be inaccurate.
People in the Duluth area could be better informed before planning outdoor activities.

4. Outline Ticks Lyme Disease Collecting Ticks GIS Borrelia Burgdorferi
Life cycle of ticks, life cycle of disease
Lyme Disease
symptoms
Collecting Ticks
GIS
Borrelia Burgdorferi
The bacteria responsible for Lyme
Vaccines
Discussion

5. Deer Tick Habitat High concentration in northeast region of U.S.
Wooded areas, forests, over-grown grassy areas and trails
Prefer moist and humid environments
Sit on tips of grass and quest for a host
Black legged tick, Ixodes scapularis,
questing on a stick.
This is a murderous female tick trying to kill you…….

6. Deer Tick Life Cycle Year 1 – Spring, Summer Year 2, May – July
3 stages of life, 1 feeding each stage
Year 1 – Spring, Summer
Eggs hatch into larvae
Feed once and molt into nymphs
Nymphs become dormant
Year 2, May – July
Nymphs feed
At this time, the nymph may transmit disease (shown in grey)
Year 2, Oct - Nov
Adults feed primarily in Fall.
Eat, spit eggs and die
Describe cycles
Graphic courtesy of Green Pest Control MN
American Lyme Disease Foundation

7. Infested Ticks Nymphal ticks are the worst for infection
Hard to detect
Their bites cause much milder pain than adult ticks’
Ticks carry Borrelia burgdorferi (Bb) in their gut
The bacteria responsible for Lyme Disease
They’re small

8. Infectious Ticks A tick embeds its proboscis into the skin
Releases saliva that anesthetizes the area and thins the blood
Outward-flowing saliva alternates with inward-moving blood
Infection enters to body system with the saliva
video and image generated by LifeHouse Productions

9. Transfer of B. burgdorferi to Ticks
Bb occurs in nature and is picked up by rodents and other small mammals.
Deer ticks take blood meal from these small mammals -during the larval stage of life- and contract bacterium.

10. Transfer of B. burgdorferi to Humans
Bb attaches to the gut
Outer surface protein A (OspA)
Bb stays in the gut until the next meal
Blood meal
 Osp A,  Osp C
Bb goes to salivary glands where it can enter the host

11. Lyme Disease
Symptomology

12. Contracting Lyme Disease
The bite of an infested nymph or adult tick can transmit Lyme after it attaches to the host for 36 – 48 hrs
generation time of bacteria B. burgdorferi: ~ 12 hrs
It takes several hours before a large enough infectious dose of Bb can infiltrate the new host.
Nature Reviews / Microbiology

13. Symptomology of Lyme Disease
Lyme is a multisystem inflammatory disease
affects the skin in the early stage
then spreads to the joints, nervous system and may eventually affect organ systems.
Symptoms are divided into 3 stages
each stage more advanced than the previous.

14. Stage 1 Symptoms Early localized infection
Skin Rash Around Tick Bite
40 -75% present with rash
Mild Illness
Flu-like Symptoms
Fevers
Chills
Swollen Lymph Nodes
Headache
Stiff Neck
Muscle Fatigue
These symptoms may appear up to a month after infection.

15. Stage 2 Symptoms Early Disseminated Infection
Within weeks of stage one symptoms, the bacterium may spread to other parts of the body through the bloodstream
Early Disseminated Infection
Multiple rashes
Cardiac
Neurologic
Muscular

16. Long Term Lyme
STAGE 3

17. Late-Stage Symptoms
This is the most serious stage of the disease, when treatment was either not successful or never started
May occur months to years after initial infection.
Symptoms at this stage are primarily rheumatologic and neurologic, and mostly untreatable.

18. Stage 3 Also known as: Diagnosis Post-Lyme Disease Syndrome
Chronic Lyme Disease
Diagnosis
Difficult to diagnose
If symptoms persist for 6 months after treatment
Due to the complexity of symptoms and possible lack of any initial symptoms.

19. Stage 3 A systemic debilitating condition Persistent Months to Years
Damage to joints, nerves, brain

20. Symptoms Rheumatoid Arthritis
Atrioventricular conduction abnormalities
(AV heart block) ~ irregular heartbeat
Encephalopathy ~ disease on the brain
Decreased memory
Sleep Disturbances
Mood changes
Ataxia ~ nervous system
Depression
Anxiety
Symptoms are wide ranging.
Rheumatiod Arthritis occurs in almost 80% of patients.
Ataxia results in poor coordination.

21. Disease Process Bacteria penetrates blood vessels
Bacteria exits vessels in various organs and tissues
Body may fight off infection
Host immune system may attack healthy tissue
Probable cause of long term complications
There are clues to the mechanisms of Post-Lyme Disease but it is not fully understood
This allows it to travel throughout the body.
Bacteria can then infect areas all over the body.
If treatment is not received soon enough or at all.

22. Diagnosis Clinical Evidence Enzyme Linked Immunosorbent Assay (ELISA)
Western Blotting
Indirect Immunofluorescence
Detect antibodies
Lacks sensitivity and specificity
PCR 
If symptoms were present at the time of the bite.
Various lab tests show previous exposure to tick and bacteria proteins. This is useful but not conclusive because tests are positive due to any previous exposure and may not be specific to current symptoms. This again shows the difficulties in diagnosing Lyme.
These tests can be time consuming, since treatment is time sensitive these tests are typically waived.
Diagnosis of Early Lymes. Journal of Clinical Microbiology.

23. Treatment Short Term Treatment Chronic Lyme
Antibiotics can shorten EM and prevent arthritis
Penicillin
Amoxicillin
Tetracycline
Can still have symptoms of Chronic Lyme
Chronic Lyme
Risks are high and benefits are low to antibiotics
Immunosuppressive drugs
The best possible treatment is really prevention. Long term disease is usually avoided completely if antibiotics are administered in the first weeks of infection. When the illness is in an advanced stage immune suppressive drugs are a common treatment.
The Clinical Spectrum and Treatment of Lyme Disease. The Yale Journal of Biology and Medicine

24. How we did it…
Collecting Ticks

25. Our Tick Collection Methods
Materials:
Light-colored bed sheet
Hand held GPS devices
Sealable plastic containers
Methods:
We stopped at the banks of pre-selected locations listed on a GPS.
We separated into groups of two, held sheets open, and swept the ground.
After 100 yards we examined the sheet in hopes of finding black-legged ticks.

26. Our Results We collected over two days, a total of eight stops.
We found 6 ticks.
All of the ticks found were in their nymph stage and were not much larger than the point of a pencil.
Our sampling was done during the mid summer season rather than the late spring or fall
this may be why so few deer ticks were collected.
Some observations were made about the general environment in which the ticks were found.

27. How we would like to do it better…
Collecting Ticks

28. Tick Collection Methods
What criteria, procedures, and equipment should be used when collecting ticks in the wild?
Hypothesis: Our methods could be improved. Used new sheets (smooth, new smell), too much wind. Jotted down notes, needed a standardized form. Looked at 2 studies (Sweden, Wisconsin/Illinois) to get ideas.

29. Where are ticks generally located in the Midwest?
Near or in deciduous forests
Dry to mesic (moderate moisture) forests
Alfisol-type soils of sandy or loam-sand textures overlying sedimentary rock
Along ecotones -boundaries between varying ecosystems
Deciduous (hardwood) forests, not so much coniferous (softwood), dry to moderate moisture levels, Alfisol-soil (Aluminum/Iron), Ecotones (meadow/forest, small animals, deer, ticks) feed in meadows and safety in forest.

30. Constructing Dragging Equipment
70 x 90cm piece of light-colored corduroy
1cm diameter wooden dowel along leading edge
Steel rod sewn into trailing edge for added weight
Rope or wood handle to allow front edge of sheet to contact vegetation
Construction of dragging equipment – light-colored corduroy (high knap, pre-washed no detergent), wood dowel leading edge, steel rod trailing edge, rope or wood handle to allow full contact with ground.
VS.

31. Collection Techniques from Schulze/Jordan:
The same individual should perform the dragging
Consistency -speed, height
Collect hourly from dawn ‘til dusk
100m long transects (sections)
collect every 10m to prevent ticks from falling off
Randomize dragging order, direction of travel, location within each transect (left, right, center) to minimize repeated dragging of same areas
Minimize dew collection by drying sheets in between collections
Same person dragging for consistency in speed. Collect hourly dawn-dusk. 100m sections, collect every 10meters., randomize drag order, minimize dew.

32. Statistics For each sampling event use a ‘Weather Station’:
Place Weather Station in center of area, 1m above vegetation height
Ambient Temperature
Ambient Humidity
Litter temperature and humidity (digital thermometer)
At least 2.5cm below leaf litter surface but not into soil
Gathering of Statistics: Use of good quality weather station and equipment for ambient temp/humidity, litter temp/humidity.

33. Sampling Data Sheet:
Use a Sampling Data Sheet to collect and centralize all of the data (consistency).

34. Works Cited for Collection Techniques:
Shulze, Terry, Jordan, Robert. “Meteorologically Mediated Diurnal Questing of Ixodes scapularis and Amblyomma Americanum Nymphs.” Journal of Medical Entomology
Lindstrom, Anders, Jaenson, Thomas. “Distribution of the Common Tick, Ixodesricinus, in different vegetation types in Southern Sweden.” Journal of Medical Entomology

35. Global Information System
GIS

36. GIS Modeling: the Interrelationship of Ticks, Mice, and their Environment
Use an appropriate collection device
Sample small specific areas
Test ticks for Borrelia burgdorferi
Look for evidence of a pattern in the incidence of infected ticks
If specific reservoirs of bacteria are found, a map could be made based on likelihood of the existence of the bacteria.

37. What is
Borrelia burgdorferi

38. Characteristics
Named after American scientist Willy Burgdorfer who in 1982 isolated and determined the bacterium.
Lyme Disease is the most common tick-borne disease in the US.
Borrelia burgdorferi are
spiral shaped microorganism (spirochetes)
Gram-negative
Motile

39. Borrelia burgdorferi complete genome
Chromosomal Gene Summary
853 genes
793 protein coding genes
502 genes assigned a role
51 genes not assigned a role
102 hypothetical genes
DNA Molecule Summary
18 DNA molecules
28.5% G+C chromosomal bases
63.1% linear DNA bases

40. Characteristics Chemo-organotropic
derive energy by metabolizing organic molecules.
They cannot synthesize their own amino acids, fatty acids, enzyme cofactors, and nucleotides.
Microaerophilic
Too much or lack of oxygen can be harmful to them.
Catalase negative
they are unable to break down hydrogen peroxide.
Optimal growth temperature is 34° to 37°C.

41. Surface proteins on Borrelia burgdorferi
OspA
expressed while Bb is in the tick’s midgut
OspC
expressed during tick’s blood meal
allows Bb to relocate to salivary glands (36-48 hr)

42. OspC binds to Salp15 in the tick salivary gland
Facilitates transmission of Bb from tick to host
Allows Bb to evade host immune system
Has immunosuppressive activity in the host

43. Immunosuppressive activity of Salp15 within host
Salp15 binds to CD4+ of
T-cells inhibiting:
the normal production and secretion of interleukin-2
TCR-triggered calcium signals
activation of transcription factors

44. Vaccines

45. Current Vaccines Currently, there is no human vaccine on the market.
Originally approved by the FDA in 1998 to help prevent the disease, the vaccine was pulled from the market by the manufacturer in 2002 due to poor sales and concern that the vaccine could trigger arthritis problems though the FDA never found conclusive evidence that the vaccine was dangerous. (WebMD)
Currently, there is no human vaccine on the market.
One did exist called LYMErix but is no longer available.

46. Possibilities for a Future Vaccine
Salp 15 is the protein that enables the bacteria to enter the host initially undetected.
If there is some way to produce a vaccine with Salp15, this could allow the host’s body to recognize and fight off the bacteria faster and more efficiently.
If there are other ways to degrade the protein in the host’s body the bacteria would become vulnerable to an immune response.

47. Problem Based Learning
Mike,
CHRISTINA,

48. Discussion Prevention Life cycle interruption Human immunity Habitat
Surface protein
Human immunity
Salp 15
glycoprotein