Damminix

From Wikipedia, the free encyclopedia

Damminix is a product used in the control of ticks that spread Lyme disease. It was developed by researchers at Harvard University.

1 How it Works: Theory
2 Alternatives: Biocontrol and Chemical
3 How it Works: Practice
4 Technology Review
5 More Information

[edit] How it Works: Theory

Mice are the primary source of infection for the ixodid ticks (deer tick, Ixodes Scapularis or Ixodes Dammini, I. Pacificus, I. Ricinis (in Europe) that carry Lyme Disease spirochetes (Borrelia burgdorferi). The Damminix (named for I. Dammini, a less used name) product targets the ticks on the mice without harming the mice. Mice are always gathering nesting material. The Damminix tick tubes contain nesting material (cotton) impregnated wth a proven acaricide (miticide / (permethrin). The field mice are able to do the rest: collecting the cotton, getting the tick-killing agent onto their fur in their nests, and killing ticks as they attach. Permethrin does not harm mice, (or other mammals or birds). Damminix is especially useful as it is not necessary to blanket spray a given area (and run any inherent risks due to chemical exposure), the treatment is highly localized due to the direct self selection behaviour of the disease vector (mice looking for nesting material), this greatly reduces the exposure risks to humans that might otherwise occur. A similar technology is used in a rodent fur mite control product, MiteArrest.

Damminix appears to help control tick populations, particularly in the year following initial use. Note that it is not effective on the West Coast.

Other tick-killing spray pesticides that have been used include those containing diazinon, chlorpyrifos, and carbaryl. Animal studies have reported severe toxic effects associated with these chemicals. Some of these agents in fact are being phased out for home use. If there is a high probability of human exposure, parents should consider the effects of a very negligible risk for a highly treatable infection versus potential excessive use of possibly harmful chemicals.

Image:Mousenesting.jpg

[edit] Alternatives: Biocontrol and Chemical

A potential alternative to Damminix is fipronil. It is used in the the Maxforce Tick Management system (from Aventis and Bayer), in which fipronil is painted onto rodents attracted to plastic baitboxes. This product requires professional installation. As of June 2006, this product is no longer available. (http://www.maxforcetms.com). The reason appears to have been that in 2005, there were selective reports of grey squirrels "chewing" into some Maxforce TMS boxes in areas of the northeastern United States, compromising the child resistant box. Due to this problem, the US Federal Environmental Protection Agency (EPA) has asked that all similarly designed TMS boxes applied in 2006 be covered with a protective shroud capable of preventing squirrel damage (http://www.maxforcetmspro.com/).

A natural method of controlling tick populations appears to be the use of guinea fowl on the property. While effective, the fowl have a reputation of being noisy. The Ichneumon wasp is also cited as a tick parasite.

[edit] How it Works: Practice

The biodegradable tubes are spaced at 15-foot intervals in mouse habitat areas and left out for the mice to find. Application twice a season (spring and fall) is recommended. The effectivity of the treatment increases as the number of contiguous properties employing the treatment increases. This product targets the tick life cycle only in the eastern US. It is avaialble only in MD, PA, NY, RI, CT, NH, NJ and MA.

[edit] Technology Review

Review of Effectiveness of a Host-Targeted System as an Effective Component of Integrated Lyme and Tick-Control Strategies

TOTT Inc., York, PA, ticktubes at verizon dot net

Abstract:

Ticks are second only to mosquitoes as vectors of human disease, both infectious and toxic (Edlow, 2005). Generally, tick-borne diseases correspond to a specific tick-host combination, and are limited in their geographical extent. No single solution for eliminating or preventing tick borne diseases can be foreseen. Ticks are difficult to control, but intelligent application of host-targeted permethrin-based ixodid control measures can be shown to be effective. In combination with commonsense safety measures, an integrated strategy is emerging to reduce human and animal exposure to ticks that may carry Lyme disease and other diseases.

Background: Permethrin as an Effective Acaricide

Lyme disease is a multiple-organ-system, immune-mediated inflammatory disorder transmitted by the bites of ixodid ticks infected with borrelia burgdorferi (Couch, 1992). Post-contact risk mitigation seems to be less effective. Wormser (2005) reports that only 20% of those infected with Lyme by the deer tick are aware of any tick bite, making early detection difficult. Tick bites usually go unnoticed due to the small size of the tick in its nymphal stage, as well as tick secretions that prevent the host from feeling any itch or pain from the bite.

Tick repellents immediately suggest themselves as a strategy to control human and animal exposure. This article explores proven and effective methods of deploying tick repellents. Control of exposure to ticks using permethrin, a synthetic pyrethroid chemical, before the tick has a chance to contact humans or animals, is a time tested and proven tactic (Nolan, 1979). Permethrin has been shown to be effective against multiple varieties of ticks, and has been used to protect humans (Lane, 1984), pets (Stone, 1994), and rodents (Spielman, 1988), as well as exotic animals such as komodo dragons and leopard tortoises (Burridge, 2002 and 2004).

Achieving understanding that deer serve as hosts for the reproductive stage of this tick, that white-footed mice serve as the reservoir of infection, and that nymphs are most abundant in early summer and must attach for 2 days before infection is transmitted, has been a long hard road. Along the way, several animals (including voles, deer and catbirds) had to be researched and evaluated as reservoirs of Lyme (Tallekint, 1993, Mather 1988, 1989a, 1989b).

An Innovative Host-Targeted Application Method

A variety of methods have been developed to prevent human infection by the Lyme disease spirochete in the northeastern United States, mainly based on the observations that nymphal black legged ticks (ixodes scapularis/dammini) serve as vector.

Broad-based methods are somewhat effective, but cause great environmental impact. Destruction of mouse habitat, but not of mice has been reported to be locally effective. Nondestructive acaricidal treatment of deer proved sporadically effective, but the elimination of these hosts resulted in reduced transmission after several years. Treatment of mice by means of acaricide-impregnated bedding material effectively reduced transmission, in a lab environment (Spielman, 1988).

This gave rise to the idea of developing a host-targeted tactic: Damminix. This product targets the ticks on the mice without harming the mice. Mice are always gathering nesting material. The Damminix tick tubes contain nesting material (cotton) impregnated with a proven acaricide. The biodegradable tubes are spaced at 15-foot intervals in mouse habitat areas and left out for the mice to find. Application twice a season (spring and autumn/fall) is recommended. The effectivity of the treatment increases as the number of contiguous properties employing the treatment increases. The field mice are able to do the rest: collecting the cotton, getting the tick-killing agent onto their fur in their nests, and killing ticks as they attach. Damminix is especially useful as it is not necessary to blanket spray a given area (and run any inherent risks due to chemical exposure), the treatment is highly localized due to the direct self selection behavior of the disease vector (mice looking for nesting material), this greatly reduces the exposure risks to humans that might otherwise occur.

The use of Damminix has been proven in multiple studies. In an early study, Mather et al. (1987) showed that distribution of permethrin-treated cotton was a means for preventing transmission of the Lyme- and babesiosis pathogens. Permethrin-treated cotton, intended as rodent nesting material, was distributed in wooded sites, in order to kill immature ixodid ticks.

Mice captured after permethrin-treated cotton was distributed, were infested by 90% fewer ticks compared to those captured in adjacent nontreated sites, a difference that continued throughout the 4-month period of observation. On average, 72% of all mice captured in treated sites were free of ticks, while virtually all mice captured in nontreated sites were infested.

An independent study (Deblinger, 1991), showed a virtual eradication of nymphal host-seeking ticks on a private, large-area (7.3ha) resort site. The authors felt that they had confirmed the efficacy of Damminix for reduction of the abundance of vector ticks and thereby contributed to the protection of humans against Lyme disease at the site. Even studies somewhat critical of Damminix (Stafford, 1992, 1991), concede a substantial reduction in subadult tick counts on white-footed mice.

The method of application is also important, it appears. The easy access to cotton offered by Damminix may be important. A study in California attempted to duplicate Damminix’s results with metal tube containers (LePrince, 1996). They found that while the cotton was accessible to some rodents, the targeted woodrats did not show a decrease in tick count. The product did eliminate sylvatic fleas.

Summary

There is encouraging news in both the treatment and prevention of Lyme disease. Avoidance of heavily tick-infested areas, personal protection using proper clothing, and prompt removal of attached ticks remain the most effective protective measures (Jeanson, 1991).

Intelligent biocontrol, with minimal habitat impact, may be achieved using Damminix, a biodegradable product with permethrin-impregnated nesting material for white-footed mice. This conclusion is borne out by multiple studies. Many other prophylactic measures are available and could be efficiently integrated into schemes to reduce the abundance of vectors (Jaenson, 1991). However, since the ecology of the infection varies greatly between different localities it may be necessary to apply different combinations of control methods in different endemic regions.

References (Alphabetical)

Burridge MJ, 2004, with Simmons LA, Condie T, Control of an exotic tick (Aponomma komodoense) infestation in a Komodo dragon (Varanus komodoensis) exhibit at a zoo in Florida, J Zoo Wildl Med., Jun;35(2):248-9.

Burridge MJ, 2002, with Peter TF, Allan SA, Mahan SM, Evaluation of safety and efficacy of acaricides for control of the African tortoise tick (Amblyomma marmoreum) on leopard tortoises (Geochelone pardalis), J Zoo Wildl Med., Mar;33(1):52-7

Couch P, Johnson CE, 1992, Prevention of Lyme disease, Am J Hosp Pharm., May;49(5):1164-73.

Deblinger RD, 1991, with Rimmer DW, Efficacy of a permethrin-based acaricide to reduce the abundance of Ixodes dammini (Acari: Ixodidae, J Med Entomol., Sep;28(5):708-11.

Edlow, JA, 2005, Tick-Borne Diseases: Emergency Medicine - Infectious Diseases. www.emedicine.com.

Jaenson TG, 1991, with Fish D, Ginsberg HS, Gray JS, Mather TN, Piesman J, Methods for control of tick vectors of Lyme borreliosis, Scand J Infect Dis Suppl., 77:151-7.

Wormser G, 2005, with Masters E, Nowakowski J, McKenna D, Holmgren D, Ma K, Ihde L, Cavaliere L, Nadelman R, Prospective clinical evaluation of patients from Missouri and New York with erythema migrans-like skin lesions, Clin Infect Dis 41 (7): 958-65.

Lane RS, 1984, with Anderson JR, Efficacy of permethrin as a repellent and toxicant for personal protection against the Pacific Coast tick and the Pajaroello tick, J Med Entomol, Nov 29;21(6):692-702.

Leprince DJ, 1996, with Lane RS, Evaluation of permethrin-impregnated cotton balls as potential nesting material to control ectoparasites of woodrats in California, J Med Entomol, May;33(3):355-60.

Mather TN, 1987, with Ribeiro JM, Spielman A, Lyme disease and babesiosis: acaricide focused on potentially infected ticks, Am J Trop Med Hyg., May;36(3):609-14.

Mather TN, 1989a, with Wilson ML, Moore SI, Ribeiro JM, Spielman A, Comparing the relative potential of rodents as reservoirs of the Lyme disease spirochete (B. burgdorferi), Am J Epidemiol, Jul;130(1):143-50.

Mather TN, 1989b, with Telford SR 3rd, MacLachlan AB, Spielman A, Incompetence of catbirds as reservoirs for the Lyme disease spirochete (Borrelia burgdorferi), J Parasitol. 1989 Feb;75(1):66-9.

Mather TN, 1990a, with Telford SR 3rd, Moore SI, Spielman A, Borrelia burgdorferi and Babesia microti: efficiency of transmission from reservoirs to vector ticks (Ixodes dammini), Exp Parasitol. Jan;70(1):55-61.

Nolan J, 1979, with Roulston WJ, Schnitzerling HJ, The potential of some synthetic pyrethroids for control of the cattle tick (Boophilus microplus), Aust Vet J. 1979 Oct;55(10):463-6.

Spielman A., 1988, Prospects for suppressing transmission of Lyme disease, Ann N Y Acad Sci. 539:212-20.

Stafford KC 3rd., 1992, Third-year evaluation of host-targeted permethrin for the control of Ixodes dammini (Acari: Ixodidae) in southeastern Connecticut., J Med Entomol., Jul;29(4):717-20.

Stafford KC 3rd., 1991, Effectiveness of host-targeted permethrin in the control of Ixodes dammini (Acari: Ixodidae), J Med Entomol., Sep;28(5):611-7. Erratum in: J Med Entomol 1992 Mar;29(2):376.

Stone BF, 1994, with Shipstone MA, Mason KV, Cunningham M, Wong CW, Efficacy of permethrin in controlling the Australian paralysis tick Ixodes holocyclus and the cat flea Ctenocephalides felis on dogs, Aust Vet J, Mar;71(3):90-1

Talleklint L, 1993, with Jaenson TG, Mather TN, Seasonal variation in the capacity of the bank vole to infect larval ticks (Acari: Ixodidae) with the Lyme disease spirochete, Borrelia burgdorferi, J Med Entomol, Jul;30(4):812-5.

Telford SR 3rd, 1988, with Mather TN, Moore SI, Wilson ML, Spielman A, Incompetence of deer as reservoirs of the Lyme disease spirochete, Am J Trop Med Hyg., Jul;39(1):105-9.