USDA Studies: Ivermectin for Tick Control http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8667385&dopt=Abstract Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX 78028-9184, USA. Whole-kernel corn was treated with 10 mg ivermectin per 0.45 kg corn and fed at rate of approximately .45 kg/deer per day to white-tailed deer confined in the treatment pasture, whereas deer in an adjacent control pasture received a similar ration of untreated corn. Treatments were dispensed from February through September of 1992 and 1993, and free-living populations of lone star ticks. Amblyomma americanum (L.), were monitored in both pastures using dry-ice traps to quantify nymphs and adults and flip-cloths to assay the relative abundance of larval masses. Control values that were calculated for all ticks collected in both pastures during 1993 showed 83.4% fewer adults, 92.4% fewer nymphs and 100.0% fewer larval masses in the treatment versus control pasture. Serum ivermectin concentrations in treated deer averaged 21.7 and 28.3 ppb during 1992 and 1993, respectively. These values compared favorably with the goal concentration of 30.0 ppb which was anticipated under ideal conditions. This study demonstrates that a freely consumed, systemically active acaricidal bait ingested by white-tailed deer under nearly wild conditions can significantly reduce the abundance of all stages of free-living lone star ticks. http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=115671 The effectiveness of the endectocide, ivermectin administered daily to cattle infested with all life stages of B. microplus was evaluated. Cattle were treated at dose rates of 25 and 50 mcg of ivermectin per kg of body weight for a period of 21 days. While both ivermectin treatment doses were highly effective (>99% control), the 50 mcg/kg/d dose was more effective than the 25 mcg/kg/d dose against all life stages of the tick. The presence of ivermectin in the blood of the cattle caused high mortality in the ticks, as well as producing dramatic adverse effects in the reproductive capability of the ticks that were able to survive and detach from the cattle. Based on the results of this study, the potential for use of ivermectin and other acaricides with similar chemistries is encouraging. The use of these types of acaricides applied by different delivery systems, such as long-term boluses or medicated feed systems has great promise for future applicability in the Boophilus eradication program.... ...overall control achieved at both doses of ivermectin was >99% against all parasitic stages, the 50 mcg/kg/d dose was more effective (P http://www.afpmb.org/pubs/misc/researchreview2004/4b-Pound.ppt http://live.psu.edu/story/19217 Deer-free areas may be haven for ticks, disease Wednesday, August 30, 2006 -------------------------------------------------------------------------------- University Park, Pa. -- Excluding deer could be a counterproductive strategy for controlling tick-borne infections, because the absence of deer from small areas may lead to an increase in ticks, rapidly turning the area into a potential disease hotspot, according to a team of U.S. and Italian researchers. "Deer are referred to as dilution hosts or dead-end hosts," says Sarah Perkins, a postdoctoral researcher at Penn Stateâs Center for Infectious Disease Dynamics. "They get bitten by ticks but never get infected with tick-borne pathogens, such as the bacteria causing Lyme disease." However, deer are critical to adult female ticks in the last stages of their three-part lifecycle. Ticks use them for a final blood meal before dropping off to produce thousands of eggs, Perkins explains. Currently, health officials believe that removing deer from the equation could disrupt the tick lifecycle and leave fewer ticks to feed on rodents, which, unlike deer, can transfer a range of tick-borne pathogens. Ultimately the tick-borne disease will fade out. However, previous field studies show that removing deer sometimes leads to higher tick densities and sometimes lower, and the outcome seems dependent on the size of area from which deer are excluded. "Very few studies have looked at how removing the deer affects the intensity of tick bites on rodents, and how it relates to the size of the area from where the deer are excluded," explains Perkins, whose findings are published in the current issue of the journal Ecology. Researchers first collected data from published information on tick densities in deer excluded areas ranging in size from roughly 2.5 acres to 18 acres. Next, over a six-month period, they captured rodents from a 2.5-acre deer excluded area in the Italian Alps in a known hotspot for tick-borne encephalitis -- a disease passed to humans through the bite of an infected tick. "From previous studies we found that tick densities decreased in (geographically) large areas and increased dramatically in smaller areas," suggesting that there is a threshold area - from where deer are excluded - for tick populations to either increase or decrease, notes the Penn State researcher. Statistical analyses of ticks on the captured rodents indicated that compared to the control areas, the deer-excluded areas hosted a significantly higher number of nymph and adult female ticks, as well as a high prevalence of tick-borne encephalitis. Because tick-borne encephalitis is transmitted only between ticks feeding on these rodents, the findings suggest how small deer-free areas could quickly turn into a disease hotspot. "This goes somewhat against conventional wisdom. When you remove deer, it does not always reduce the tick population," says Perkins. "If you were to exclude deer from hundreds of acres, tick numbers will fall. But in an area less than 2.5 acres, you are more likely to increase tick density and probably create tick-borne hotspots." Researchers say the study demonstrates how the strategy of keeping deer away may work only for large areas but is likely to amplify tick populations in smaller areas. Fragmented patches of forest and small parks that are off-limits to deer could also turn into a disease reservoir, they caution. "We need to be cautious about keeping deer away from small areas, even peopleâs backyards, as it might only lead to more ticks that are infected with tick-borne pathogens," says Perkins. She adds that forest areas deer consistently avoid also have the potential of turning into a haven for tick-borne disease. Other authors of the paper include Isabella M. Cattadori, postdoctoral scholar, and Peter J. Hudson, the Willaman Professor of Biology, both at Penn State University, and Valentina Tagliapietra and Annapaola P. Rizzoli, Centro di Ecologia Alpina, Italy. A grant from the Autonomous Province of Trento, Italy, supported this work. The Penn State Center for Infectious Disease Dynamics is at http://www.cidd.psu.edu/. Contact Amit Avasthi axa47@psu.edu http://live.psu.edu 814-865-9481 Contact Vicki Fong vfong@psu.edu http://live.psu.edu 814-865-9481 The Pennsylvania State University © 2006 http://www.wildlifeprotein.com/index.cfm/fa/categories.main/parentcat/16705

I hope your treatment does the trick! I've already gotten Lyme disease this year too. The doxycycline is a big PITA to take. Nothing with calcium within two hours of taking it, so it messes with morning tea and vitamins. Then there is the possible photosensitivity and I'm always outside - that's how the ticks find me for goodness sake! Just regular tick bites without the LD bother me for over a month so I must be allergic to tick spit too. Nasty little creatures!

I must say I'm not all that impressed with what has happened since. The last time I was bitten by a deer tick, my doctor ordered that the tick be tested, and started me out on antibiotics in the meantime. I'm not crazy about taking anything, but I think in this case it's a good idea. However, this time all he ordered was an ID on the tick. I brought the tick to the lab thinking it would be tested for Lyme like last time, but no, the order was for an ID. I'm sure it's a deer tick, and I hope my insurance will cover this stupid test. I handed it to the girl at the lab, and she said, "It looks like a deer tick." Yup.

DEFINITION: Lyme Disease is an infectious disease caused by a spirochete-form bacterium (Borrelia burgdorferi), and was first identified in the 70's in children in Lyme, Connecticut who exhibited arthritis-like symptoms. The primary means of transmission to humans in the east is the deer tick, AKA black-legged tick, (Ixodes scapularis) which harbors the bacterium in its gut. There are reports that Lyme Disease can also be transmitted by biting flies, although this is rare. OCCURRENCE: The most significant areas of infection are on the eastern seaboard, from Massachusetts to Maryland, with other hotspots in the Great Lakes area and in a few localities on the Pacific coast. However, isolated cases have been reported in virtually all states, including Alaska and Hawaii. Anybody who works outside in these areas is at danger of infection. LIFE CYCLE: The life cycle of the bacterium involves deer, white-footed mice, ticks and humans (other animals can be involved, but these are the most relevant to us). The ticks apparently prefer to feed on deer and then drop off and lay their eggs in the spring in moist litter in the woods or overgrown grassy areas. The eggs hatch into larvae, which are not yet infected. The larvae attach to the mice, which may be infected, and become infected by the host mouse. When the larvae are finished feeding, they drop off the mice in late summer, and develop into nymphal ticks which retain the bacterium if the larvae were infected. The nymphs go dormant for the winter and then, in early spring start looking for a new host, which may be human. The major threat to humans is the nymph, which feeds and infects in late spring to summer, usually May to July. The nymph is tiny and hard to see when it's attached, so it may not be noticed. The nymph molts into an adult tick in the fall. The adult then goes looking for a big meal, typically a deer or a human and can also infect at this stage. However, the adult tick is easier to see because it's bigger (not huge, but detectable). When it's finished eating, it drops off, the female lays eggs, and the cycle is off again. SEASONAL ISSUES: The major danger of infection is in late spring and summer when the tiny nymph is feeding on people, but you still need to be vigilant in the fall when the adult tick is around. There are also some interesting annual/biennial connections between oak trees, acorns, ticks, mice and gypsy moths. Ticks in the east are commonly found in deciduous, oak forests. Studies indicate that oaks have a 2 to 5 year cycle where one year a large number of acorns are formed, followed by leaner years. The deer and the mice thrive when they've got lots of acorns to eat, and the ticks are happy because there are lots of hosts (deer and mice). What it all means is that the frequency of Lyme Disease infections seems to be higher a year or two after there are lots of acorns (gypsy moths are less frequent because mice eat the moth pupae (great choice, Lyme Disease or gypsy moths). SYMPTOMS OF DISEASE: When a tick bites you, it buries its head in your skin and begins to feed on your blood. The bacterium usually isn't transmitted to you until at least a day, and often 2 to 4 days later. Usually about 7 to 14 days after the bite of an infected tick, a large, circular, red "bulls-eye" rash occurs, often accompanied by headache, fever, fatigue, and muscle and joint aches. Severe itching is uncommon but can be present. The "bulls-eye" rash doesn't always occur, and you can still be infected and not show many of these symptoms. If the infection is untreated, the disease can progress to a generalized condition with neurological, muscular, arthritic, encephalitic and cardiac complications, joint swellings and cognitive problems, sleep disturbances and personality changes. The symptoms can recur over many years. It's rarely fatal, but can really mess up your life. DIAGNOSIS: Diagnosis depends on a combination of lab tests which detect antibodies to the bacteria (the "Lyme titer"), the history of a tick bite, characteristic symptoms of infection, the appearance of a rash, and the willingness of the doctors to take you seriously. Doctors are often reluctant to prescribe antibiotics without definitive lab results, and these tests will not be positive in the first few days or sometimes weeks or a month after the tick bite. The antibodies are slow to develop so a test will often be negative even though you're already miserable. It's important for you to document the symptoms (keeping a calendar is very good) and to keep nagging the doctors so that you can be treated early in the course of the disease. Keeping the tick (on sticky tape) may be useful both to identify the tick species and to indicate whether it's swollen enough to have been feeding for more than a day. If you feel the doctors aren't taking you seriously, and you live in an area where Lyme Disease is common, find another doctor who will consider treating you before the titer comes back positive. PERSONAL HISTORIES OF INFECTION: martieinct posted this account of her experiences with Lyme Disease in Connecticut: "I've held off posting because just thinking about how I felt the two times I definitively had Lyme makes me shudder. The two times were very different and that is why misdiagnosis occurs so often. When Lyme was first discovered, everyone was looking for ring rashes. My rash covered my entire torso and went into, rather than out of, the skin. It itched and hurt terribly, but no joint or muscle pain. It took a NYC dermatologist to get the final diagnosis AFTER two titers had come back negative. Three weeks of antibiotic cleared it up that time around. The second time, three years later, I felt like someone poured cement all over my body and made me run a marathon. The "rash" was confined to a 1" x 1" area and it took me several days to find it since it had no symptoms of its own. My general practitioner ran a titer "just to see" and it came back glaringly positive. This time around, the standard antibiotic course didn't work and I needed to get the IV treatment. What bothers me most about this disease, other than the fact that a lot of people ignore the very simple tasks one can take to avoid it, is the vastness of the symptoms. It seems that no one person's experience is the same as another. This makes it tough to diagnose right away. Thus, in my neck of the woods all the GP's do a Lyme titer automatically when anyone comes in with unexplained symptoms that have anything to do with a rash, achiness, long-term but low grade fever, etc. The titers still aren't 100% accurate all the time, but I give these folks credit for not messing around. The first time I had it, the three months it took to get me on antibiotics were torture. This is a "new" disease and is fickle. I'm glad that we're talking about it because the more who know, the less likely you'll get it or if you do, can get treatment right away. If you think you've been exposed, Don't Wait to get the Titer and Go to Another Doctor if they won't order you the titer immediately. There are support groups starting to pop up for folks who have had the disease and are getting recurrences. I've not gone, but it doesn't surprise me .... Martie" chelone who lives in southern Maine reports: "They did the Lyme titer on me when I caved in and saw a doctor after nearly one week of feeling so lousy I couldn't get off the couch. It came back NEGATIVE (and it cost nearly $300!); I was told I had "summer flu". Until I found the rash/ring on my left hip. THEN the doctor got serious, and within 18 hrs. of taking the antibiotic I felt normal. This disease is nothing to take lightly. It's insideous, presenting so many diverse symptoms that it's virtually impossible to "nail down" a diagnosis on that basis alone. We have a very high incidence of it in my community and the doctors at the local hospital are pretty "hip" to it now. Nearly every person I know on my road has had it at least once... it damn near killed a friend who is HIV positive (heart failure), and wrought havoc on a neighbor in his 70s. It's serious stuff, so be careful about ticks and meticulous in noting bites. Nag your doctor! you are your best advocate. Please note that the experience I referenced above happened in 1996! I remember because I was watching the Olympics and remember the "bombing". Awareness has increased markedly since then. I had one other "occurence"; in '04. I had a very nasty bite site on my left buttock. And the good doctor didn't hesitate to prescribe the antibiotic... mostly because I had my calender to quantify the bite date!" circa1825 who lives in south central MA reports: "I just wanted to warn people about deer flies being a vector for Lyme's Disease. Last year, a deer fly landed just below my ankle. I smacked it with my hand and was pretty happy that I'd gotten it before it bit me. At some point after that, the spot where it had landed started to swell up until I couldn't see my ankle, and the spot turned red, then purple, and then black. I thought maybe the deer fly had bitten me after all and I was allergic to it, just like I am to anything that stings. I started reading about deer flies and found out that people can get Tularemia from deer flies. Tularemia (deer fly fever) is a bacterial infection and is actually on the government's "watch list" for bioterrorism. Between that and the fact that I was already concerned that my foot might be rotting off, I went to the doctor. She took pictures of my foot, drew a circle directly on my foot around the area so I could monitor its spread, put me on anti-biotics (in case it was Tularemia and also because she saw that one of my ears was red inside), and sent me out to get tested for Lyme's Disease and bacteria. The test came back negative. Things got worse after a few days, so she put me on Prednisone. When things continued to get worse, she had me tested again. This time the test was positive for Lyme's and I got put back on anti-biotics. Apparently there is about a two-week window where Lyme's may or may not show up after a person has been bitten. I learned that getting Lyme's from a deer fly is much more rare than getting it from a tick, but something I saw on the Internet said that CT, RI, NY, NJ, PA, MD, WI, and MN account for 92% of cases of Lyme's. On top of that, Nantucket County, MA was the highest in 1999 with almost 1 in 100 people contracting the disease that year. I live in south central MA, so just beware." TIME CONSTRAINTS OF TREATMENT: Antibiotics such as doxycycline and amoxicillin are very effective in the early stages of the disease. As the disease progresses, these antibiotics can sometimes be provided on an outpatient basis. However, if you become extremely ill, or your physician recommends it, the later stages may require a lengthy stay in the hospital (a month or more) while they drip antibiotics intravenously into you. This is an excellent reason to keep after your doctors so you get treatment early enough to reverse the disease. Needless to say, a lengthy hospital stay will seriously impact your gardening time. PREVENTION - VACCINATION: There is a vaccine (Lymerix) against the Lyme Disease bacterium which has been used on people and animals. However, the manufacturer withdrew the vaccine from the market in 2002. According to a representative of the Lyme Disease Task Force in Connecticut "The vaccine was pulled off the market after a lawsuit was brought against the company manufacturing the drug. Those that were given the vaccine had reverse reaction which made them even sicker. They had previously been diagnosed with lyme disease and it was discovered that this group of people were at serious arthritic risk after receiving the vaccine" The manufacturer's position is "... GlaxoSmithKline announced the discontinuation of. LYMErix . in the USA as a result of poor demand for the product", (GSK 2002 Annual Report). The future of vaccination is uncertain, although another vaccine may be in preparation. PREVENTION - AVOID TICK HABITAT: The ideal solution would be to stay away from tick habitat completely; e.g., stay out of the woods, avoid moist, shady areas with lots of undergrowth or overgrown grassy areas and anywhere where there are a lot of deer and mice. However, even if you yourself are willing to give up a walk in the woods in spring and summer, and stay away from the shrubbier areas of your garden, you would still have to somehow control your kids, dogs and cats. Not an easy task. PREVENTION - REDUCE TICKS IN THE NEIGHBORHOOD: A more realistic approach is first of all to try to reduce the number of ticks in your vicinity and particularly the number of infected ticks. If your yard is surrounded by woods you could have your woods line sprayed with an appropriate insecticide/miticide. Your entire yard need not be sprayed, only the woods line (maybe 15 or so feet into the woods), if done properly this could reduce your overall tick population by as much as 70%. Ticks hide out in shady areas. They don't like sunny dry conditions, so you will find the largest tick population along the woods line, in tall grass, in thick ground covers (like pachysandra), etc., so with this in mind, don't put your child's swingset or sandbox near shady or groundcover cluttered conditions. Also keep your lawn properly mowed and don't plant pachysandra or other dense ground covers near or along frequently used walkways or around the foundation of your house. Have your pets treated accordingly with a product such as Frontline, and/or have them vaccinated if possible. Clearing leaf litter and removing brush piles is also recommended in severely infested areas, but this can conflict with the common gardening practices of mulching, developing compost, and supporting wildlife habitat. You have to strike a balance between the likelihood of infection and desirable gardening procedures. Chickens and Guinea fowl have been suggested as a good natural control to eat ticks. Wild turkeys may also be useful if they live in your area. If the Lyme Disease frequency is severe in your neighborhood, the community may be willing (or can be convinced) to adopt methods to control ticks on deer and mice. There are products that can be applied via deer feeding stations and provided to mice for nesting which will kill ticks. PREVENTION - CLOTHES, SHOES AND REPELLENTS: If you're going into tick-infested areas, you should minimize the amount of exposed skin. Under ideal conditions you should wear a hat, a long-sleeved shirt, and long pants tucked into socks and boots. Apply DEET to your skin and clothes, and permethrin to your clothes. Always follow the directions scrupulously for the health of yourself and your family. Light colored clothes are best so you can see the dark ticks and get rid of them before they attach to you. If you're not willing to bundle up in the middle of a hot summer, then concentrate on your ankles and legs since ticks are most likely to be found at that height. PREVENTION - INSPECT AND REMOVE TICKS: Of supreme importance is a daily inspection of yourself, your kids, and your pets to remove the ticks before they can do damage. In particular, check shady, moist areas, e.g. the scalp, groin, and armpits. There are other ticks around besides deer ticks. Deer ticks are smaller (a couple of millimeters, tops) but all ticks should obviously be removed ASAP. If you find an embedded tick, remove it with fine tweezers. Get a good grip on the body and pull out slowly. Forget about the hot matches, vaseline, nail polish removers, ammonia, whatever - you might end up with a mangled tick still pumping away into you. And damaged skin as well. Once you've got the tick out, clean the bite with alcohol and apply a topical antibiotic such as neosporin. Even if some of the mouth parts stayed in the skin, the bacterium was removed with the tick's body. Save the tick on sticky tape just in case you develop symptoms. *See below for additional information on Tick Removal. OTHER TICK-BORNE DISEASES THAT CAN COEXIST WITH LYME: In case you're not distressed enough by now, you should know that the same tick that gives you Lyme Disease can also give you Erlichiosis and/or several diseases caused by the Bartonella organism. REFERENCES: The Centers for Disease Control and Prevention (CDC) is a federal agency which publishes comprehensive and up-to-date information on Lyme Disease. A web search on Lyme Disease and/or CDC will start you on the way to a lot of information. ...................................................................................................................... *ADDITIONAL INFORMATION ON TICK REMOVAL jesssam objects to the use of tweezers for removing ticks and states: "Very thorough article on ticks. But your advice to remove ticks with tweezers is not recommended because you will be squeezing the body and therefore using it like a tiny syringe to possibly inject pathogens into your body. Here are some links to sites with recommendations as well as tick removal tools which might be wise to have on hand if you live where ticks are a problem. I do and I do. " For some of the links, search the internet for Placerville Veterinary Clinic. The website has a section on Tick Removal (quoted below) and an excellent discussion of different tools. Keep in mind that they sell one type of tool, so the analysis may be biased. Source: Placerville Veterinary Clinic "Remove Ticks How to remove ticks: Being careful not to squash the tick, grasp it by the head with fine-tipped curved forceps and slowly pull straight out. How not to remove ticks: Don't remove the tick with your fingers. 
In many areas of the country the tick is likely to be carrying Lyme disease or other pathogens that can harm humans. 

 Don't squash the tick.
 The spirochete that causes Lyme disease hibernates in the tick's intestine, sometimes for years, waiting for a signal that a new host is available. This signal, an influx of fresh blood, triggers an enormous increase in the spirochete population. After filling the intestine, spirochetes move to the salivary glands and enter the their new host along with anticoagulants and anesthetics produced by the tick. Squashing the tick spreads spirochetes everywhere. Don't try to burn the tick or smother it with Vaseline etc.. 
Once that tick is firmly fastened in place, it takes time for the tick to detach itself and depart. No matter how badly the tick may wish to leave quickly, it simply can't. A burning cigarette may kill the tick but won't make it fall off. Ticks can live without air for a long time, so attempts to smother it allow disease transmission to continue for several hours. Anything that upsets or harms the tick without removing it can theoretically cause the tick to regurgitate its stomach contents back into the host, increasing the likelihood of disease transmission. Don't twist the tick out. 
Ticks aren't threaded. Your best chance of removing the head is pulling straight out with steady traction. Twisting invariably leaves the head behind. Because people who twist ticks don't feel the head break off they think it has been removed."