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'll let you know how it goes. I'm not sure I'll be able to tell whether the product has made a difference. My rock garden area is a tick festival. I actually found a live tick on my clothing while spraying the stuff! I guess I should have sprayed it directly on that tick to see what would happen. I think the product is meant more for a mown lawn area rather than an overgrown rock garden. I personally will be wearing clothing treated with permethrins and I will use DEET on myself if necessary while gardening there. My county is #2 in the country for incidence of Lyme Disease so that is a big concern of mine and for me at least it outways other concerns. However, I refuse to spray the ground or foliage with anything nasty. It's not very polite to attract birds to your feeders and then say, oops, there's poison all around so be careful. Especially the woodpeckers and hummingbirds who will eat bugs and sap from the trees. I probably wasted my $25. Anyone have any luck using tea tree oil as an insect repellant? I mean putting it on your skin. Mary Ann

I am referred to as "the tick magnet" in my household. It is not uncommon for me to walk across the lawn, spend 10 minutes in the veggie garden, and come in with a tick. I've gotten so I can spot a wood tick sitting on the top of a plant, waving its little legs and waiting to grab hold. I'm going to repeat what I said in the post from last fall that Claire linked. I live on an old farm with a mix of field, brushy growing-up field, and woods. I use bug dope with DEET, though I put it only on my clothing and I don't always use it. I own several pairs of the pyrethrin impregnated socks and I tuck my pant legs into them. (Along with my bug net during black fly season I usually look pretty dorky when I am out in the garden.) I don't really worry about ticks because during the height of the season I might find 6 or 8 on me over the course of a day, but I do take them seriously. Instead of worrying, I do a complete visual and touch check whenever I come into the house in the spring and fall. Clothes get stripped off and examined along with my body. I again do a complete visual and fingertip check at bedtime every night (until it gets too cold for the ticks to be active) standing nekkid in front of a mirror so that I can see places like under my arms and the middle of my back, etc. in case I missed any the first time around. I also comb my hair with a comb having close-set teeth and do a careful touch examination of my entire scalp. Clothing I take off doesn't go into the bedroom. I view that nightly 15 minutes as the dues I pay for being able to get out beyond the lawn areas at my house. When we first moved here I used to freak out about getting a tick, but there are so many (mostly wood ticks, though there are some deer ticks) that I just don't have the energy to get worked up about them. I'd rather put the energy in to doing careful checks afterwards since it takes a day or more for a tick to get seated and spread disease. I do this check religiously, every single night, even if I have not worked in the garden. It's part of my bedtime routine, like brushing my teeth. It is my understanding (and fits in with my observations here) that rodents are a large part of the cause of the "deer" (more accurately referred to as "black-legged") tick problem, so the tick tubes, which target the application of permethrin specifically to rodents, make good sense. I haven't used them, however, and studies vary in their evaluation of effectiveness. Last season was the first we had appreciable numbers of black-legged ticks, so we are just starting serious consideration of management for them. I haven't previously seen reference to nematodes as good for controlling ticks, so I did some reading. It seems like around here they aren't too effective since nematodes live in the soil, and when are ticks are in or on the ground, it's too cold for the nematodes to be effective. They are also more effective on adults that the nymphs that often spread disease. However, I did come across a fungus that it supposed to be better in this part of the country, Metarhizium anisopliae, that has met with EPA approval for tick control. Unfortunately, it appears to still be in the product development stages. As others have mentioned, keeping areas with brush or long grass mowed will help reduce shelter areas for ticks, and reducing areas like stone walls where rodents hide will help as well.

I've revised this How can I protect myself and my family from ticks and Lyme Disease?FAQ to include comments by jessam on tick removal. Since I can't use direct links in the FAQ, I had to just refer to the Placerville Veterinary Clinic. The direct link for tick removal is: How to remove ticks and the link for tick removal tools is: Tick removal tools A disclaimer is that the site happens to sell one sort of tool, so that should be kept in mind, but the analysis sounds reasonable to me. Claire