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Black legged Ticks. Lymes on the rise………. The Increase of Lymes in Minnesota. A local family physician inquiring about Lymes disease. Physician noted an increase of patients experiencing ring shaped rashes, headaches, and fever chills which point to Lymes .
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Black legged Ticks Lymes on the rise………
The Increase of Lymes in Minnesota • A local family physician inquiring about Lymes disease. • Physician noted an increase of patients experiencing ring shaped rashes, headaches, and fever chills which point to Lymes. • Rigid diagnosis was not made as conformation requires an diagnostic assay. • The physician expressed concern that the Minnesota Department of Natural Resources maybe inaccurate. • Duluth area people might need to be better informed before planning outdoor activities.
Lymes Disease symptomology
Contracting Lymes Disease • The bite of an infected nymph or adult tick can only transmit Lyme disease after it attaches to the host for 36 – 48 hours • the generation time of B. Burgdorferi: ~ 12 hours • Spirochetes waiting in the mid-gut of the tick begin to multiply as the tick starts its blood meal then migrate to the salivary glands where they are discharged into the host with the tick's saliva. • It takes several hours before a large enough infectious dose of spirochetes can penetrate the new host. • Most incidences of Lyme disease occur from May through September because the nymphal stage of the tick is responsible for most cases • They are too small to be easily detectable • Their bites cause much milder pain than an adult tick.
Symptomology of Lymes Disease • Lyme is a multisystem inflammatory disease • affects the skin in the early stage • and then spreads to the joints, nervous system and may eventually affect the organ systems. The symptoms are divided into three stages, each stage being more advanced than the previous.
Symptomology Stage 1 – Early localized infection Skin Rash Around Tick Bite (75%) Mild Illness Flu-like Symptoms Fevers Chills Swollen Lymph Nodes Headache Stiff Neck Muscle Fatigue Initial sign and symptoms of Lyme disease include an appearance of a rash, which has the appearance of being solid red or bull’s eye rash with flu like symptoms.These symptoms may appear up to a month after infection.
Symptomology Stage 2 – Early Disseminated Infection Neurological Problems Meningitis Encephalitis • Within weeks of stage one symptoms, the bacterium may spread to other parts of the body through the bloodstream. • infected individuals may start having acute neurological problems such as Bell's Palsy. *15% of untreated patients progress to this stage. • Meningitis, as well as mild Encephalitis is common at this stage, leading to memory loss, sleep disturbances, or changes in mood or affect.
Symptomology Stage 3 – Late Persistent Infection Polyneuropathy Pain and Numbness Cognitive Impairment Arthritis Acrodermatitischronicaatrophicans (primarily in Europe) The third and the most severe stage may occur months to years after initial infection. Symptoms at this stage are primarily rheumatologic and neurologic, and mostly untreatable.
Resources:http://www.nature.com/nrmicro/journal/v3/n2/full/nrmicro1086.htmlResources:http://www.nature.com/nrmicro/journal/v3/n2/full/nrmicro1086.html
Long Term Lyme 3 stages of Lyme Disease
Stage 1: Early Localized (previous slides) • Stage 2: Early Disseminated • Weeks to Months • Affects skin, joints, nervous system, heart • Stage 3: Late Persistent • Months to Years • Damage to joints, nerves, brain
Stage 3 • Also Known as: • Post-Lyme Disease Syndrome • Chronic Lyme Disease • Occurs 6 months after treatment
Possible Cause • If antibiotics are not received quickly, then the body may build up antibodies to B. b. These antibodies may later attack healthy tissues. • Multiple studies hint at the autoimmune process behind Lyme Disease but nothing is known.
Diagnosis • Clinical Evidence • Enzyme Linked Immunosorbent Assay • Western Blotting • Indirect Immunofluorescence • Detect antibodies • Lack s sensitivity and specificity • PCR
Treatment • Short Term Treatment • Amoxicillin • Probenecid • Ceftriaxone • Doxycycline • Tetracycline • Chronic Antibiotics • Penicillin • Erythromycin • Tetracyline
Our tick collection methods • Materials: • Light-colored bed sheet • Hand held GPS devices • Sealable plastic containers • Methods: • We began by stopping at the banks of pre-selected locations listed in the GPS. • We separated into groups of about two and while holding the sheet open, we swept the ground. • After dragging for 100 yards we examined the sheet in hopes of finding black-legged ticks.
Our Results • We continued collecting over two days for a total of eight stops. • We found six ticks. • Some observations were made about the general environment in which the ticks were found, however, very little information was recorded. • 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 ticks were collected.
Tick collection criteria Project title Michael Cherry| Dr. Ben Clarke| Bridges and Pathways Program 2010
Tick Collection • What criteria and procedures should be used when collecting ticks in the ‘wild’?
Project Overview • Where ticks are located • Survey techniques should be consistent • Use of standardized equipment • Integrity of Data Collection Criteria and methods of recording
Where are ticks 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)
Alfisol Soils • Alfisols are a soil order in USDA soil taxonomy. Alfisols form in semiarid to humid areas, typically under a hardwood forest cover. They have a clay-enriched subsoil and relatively high native fertility. "Alf" refers to Aluminium (Al) and Iron (Fe). Alfisol from East Tennessee. http://www.uamont.edu/facultyweb/francis/soilprofiles/soilprofilepage.htm
Where are ticks not located in the midwest? • Near coniferous forests • Grasslands • Wet and very damp forests • Acidic soils of low fertility and a clay soil texture • Precambrian bedrock
Construction of 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
Collection Techniques from Schulze/jordan • Same individual should perform the dragging for consistency • Speed, height • Collected hourly from 0600 – 2100 hours • 100m long transects, collect every 10m to prevent ticks from falling off • Ramdomize dragging order, direction of travel, location within each transect (left, right, center) to minimize repeated dragging of same areas • Minimize dew collection by drying on running pickup truck hood • To minimize effects of moisture on tick collection
Statistics • For each sampling event (each hour) (use of Weather Station): • Ambient Temperature • Ambient Humidity • Place Weather Station in center of area, 1m above vegetation height • Litter temperature and humidity (digital thermometer) • At least 2.5cm below leaf litter surface but not into the soil
Statistical analysis • Use of repeated measures of analysis of variance • Use of multiple linear regression to examine relationships • Use separate regressions for each species • Tolerance value of 0.1 is acceptable • Calculate temp gradient: subtract hourly litter temp from ambient • Calculate humidity gradient: subtract litter H from ambient H • Use Pearson correlation and linear regression to determine relationships between calculated gradients and numbers of questing ticks
Conclusion • Consistency regarding the gathering of ticks and in measuring and recording statistics are critical to success
Works Cited • Meteorologically Mediated Diurnal Questing of IxodesScapularis and AmblyommaAmericanum Nymphs – Terry Schulze and Robert Jordan Journal of Medical Entomology (2003) • Distribution of the Common Tick, Ixodesricinus, in different vegetation types in Southern Sweden – Anders Lindstrom and Thomas Jaenson, Journal of Medical Entomology (2003)
Possible Outcomes • Lymes disease occurances have been on the rise in the US partially due to climate change and expansion in tick population, but also due to increased human/tick interaction in fringe areas near cities. By identifying specific ecotomes required for the complex life cycles of ticks and boriela, we can possibly eliminate some of those factors in these fringe areas possibly reducing the incidence of disease being transferred to humans
GIS Modeling of the Interrelationshipof Ticks, Mice, and Ecotones • Collecting ticks while recording specific geographical data • Soil/vegetation/elevation/etc. • Analyze ticks to detect the presence of Borrielabacteria • Analyze the Data searching for patterns of Borrielain relation to the specific ecotone in which the tick was found
Investigating Lymes Disease Symptoms and Current Vaccines and Possible Future Ideas to Develop a New Vaccine. By: Nina M. Holz
Borreliaburgdorferi Complete genome
Characteristics • Borreliaburgdorferi are • spiral shaped microorganism (spirochetes) • Gram-negative • Motile • On the average, seven periplasmic flagella are located at each cell end, and these flagella overlap at the central region of the cell. • inhabit the gut of deer ticks (Ixodes scapularis). • Named after American scientist Willy Burgdorfer who in 1982 isolated and determined the bacterium. • Lymes disease is the most common tick-borne disease in the US.
Characteristics • Chemo-organotropic • derive energy by metabolizing organic molecules. • Microaerophilic • they require oxygen to survive, but only at low concentrations. Too much or lack of oxygen can be harmful to them. • Catalase negative • they are unable to break down hydrogen peroxide. • They cannot synthesize their own amino acids, fatty acids, enzyme cofactors, and nucleotides.
Characteristics • Optimal growth temperature is 34° to 37°C • Generation time of 11 to 12 hours at 35°C. • Their life cycle is directly linked to their host, and they depend on arthropod vectors (ticks) to infect mammals. • They reside in infected mammals as well as in the gut of ticks. • They multiply when there is enough blood ingested by the tick to support bacterial growth.
Chromosomal Gene Summary Genome structure DNA Molecule Summary 18 DNA molecules 28.5% G+C chromosomal bases 63.1% linear DNA bases • 853 genes • 793 protein coding genes • 502 genes assigned a role, 51 genes not assigned a role • 102 hypothetical genes
Cultivation • The organism's small genome lacks the genes that are necessary for the synthesis of amino acids, fatty acids, enzyme cofactors, and nucleotides. • In order for these spirochetes to be cultured, a very special type of medium is used called Barbour-Stoenner-Kelly (BSK) medium.
BSK =Barbour-Stoenner-Kelly • Contains serum-supplemented mammalian tissue-culture that enables the bacterium to reproduce without ever having the need to synthesize too many biological compounds. • Contains over thirteen ingredients in a rabbit serum base. • Optimal temperature for growth =32-35oC • A microaerobic environment. • Even under optimal conditions, the generation time is slow, about 12-24 hours. • BSK solidified with 1.3% agarose allows the production of colonies from single organisms.
Some Basic Background Information Regarding Ticks and Lymes Disease • The tick that passes enables animals to contract Lymes Disease is called: Ixodesscapularis. • The ticks generally feed on a wide variety of small mammals, birds, and reptiles, but prefer to feed on white-footed mice(Peromyscusleucopus), which are the important reservoir of infection in nature. • Adults prefer to feed and mate on white-tailed deer . • The infection is a bacteria calledBorreliaburgdorferi. The ticks usually get infected from feeding on a infected host. • Not all humans that get bite by ticks get Lymesdiesease • Only ticks that are infected with the bacteria can give Lymes to humans • This is generally after a prolonged amount of time feeding on the human where they can also get Lymes disease
Internal Anatomy of a Tick • Shown to the left is the internal anatomy of a tick. The picture shows the major areas involved in feeding and reproducing in the tick.
Early Onset Symptoms of Lymes Disease • Within 1-4 weeks of being bitten by an infected tick, most people will experience some symptoms of Lyme disease. • A circular, expanding rash (called erythemamigrans) at the site of the bite develops in about 70%-80% of cases. • Some people report flu-like symptoms at this stage, including fever, chills, headaches, fatigue, swollen lymph nodes, joint pain, and muscle aches.” (WebMD)
Mid-Stage Onset Symptoms of Lymes Disease • If the disease is not detected and treated in its early stages, it can extend to more areas of the body, affecting the joints, heart, and nervous system (about 1-4 months after the initial bite). • Additional rashes may occur, and there may be intermittent periods of pain and weakness in the arms or legs. • Facial-muscle paralysis (Bell's palsy), headaches, and poor memory are other symptoms at this stage, along with a rapid heartbeat and some loss of control of facial muscles.” (WebMD)
Late-Stage Onset Symptoms of Lymes Disease • This is the most serious stage of the disease, when treatment was either not successful or never started (usually occurring many months after the initial bite). • Joint inflammation (arthritis), typically in the knees, becomes apparent, and may become chronic. • The nervous system can develop abnormal sensation because of disease of peripheral nerves (peripheral neuropathy), and confusion. • Heart problems are less common, but can include inflammation of the heart muscle.” (WebMD)
Current Treatments for Lymes Disease • Most Lyme disease is curable with antibiotics, particularly when the infection is diagnosed and treated early. • Doxycycline, amoxicillin, and cefuroxime are the drugs of choice most of the time for early illness. • Later stages might require longer-term, intravenous antibiotics, such as ceftriaxone.” (WebMD)
Vaccines made for Lymes Disease • Currently, there is no human vaccine for Lyme disease. • The one that did exist -- LYMErix -- is no longer available. • 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. • There was concern that the vaccine could trigger arthritis problems, although the FDA never found evidence that the vaccine was dangerous.” (WebMD)
Possible Ideas for a Future Vaccine for Lymes Disease • Since the Salp15 protein is the protein that enables the bacteria to enter the host initially undetected, learning more about the protein anatomy and morphology would be beneficial. • If there is some way to possibly degrade the protein so that the bacteria is exposed and becomes vulnerable, I think this would allow the host’s body to fight off the bacteria faster and more efficiently with hopefully less damage to the body.
