Ivermectin resistance

Coles, C.C., Watson, C.L. and Anziani, O.S. (2001) Ivermectin-resistant Cooperia in cattle. Veterinary Record 148, 283. 

Varady, M., Bjorn, H., Craven, J. and Nansen, P. (1997) In vitro characterization of lines of Oesophagostomum dentatum selected or not selected for resistance to pyrantel, levamisole and ivermectin. International Journal for Parasitology 27, 77-81. 

Ivermectin also now plays a key role in onchocerciasis control. Annual mass treatments have led to major reductions in disease transmission. However, evidence of diminished responsiveness after mass administration of ivermectin has raised concern regarding selection of drug-resistant parasites. 

Sangster N C 1999 Pharmacology of anthelmintic resistance in cyathostomes will it occur with the avermectin millbemycins. Veterinary Parasitology 85 189-204 Tarigo-Martinie J L, Wyatt A R, Kaplan R M 2001 Prevalence and clinical implications of anthelmintic resistance In cyathostomes in horses. Journal of the American Veterinary Medical Association 218 1957-1960 Taylor S M, Kenny J 1995 Comparison of moxidectin with ivermectin and pyrantel embonate for reduction of faecal egg count in horses. Veterinary Record 137 516-518 Uhlinger C 1990 Effects of three anthelmintic schedules on the incidence of coiic in horses. Equine Veterinary Journal 22 251-254... 

Marques-Santos, L.F., R.R. Bernardo, E.F. de Paula and V.M. Rumjanek. Cyclosporin A and trifluoperazine, two resistance-modulating agents, increase ivermectin neurotoxicity in mice. Pharmacol. Toxicol. 84 125-129, 1999. 

Shikiya, K., Zaha, O., Niimura, S., Nakamura, H., Nakayoshi, T., Kochi, A., Uehara, X., Uechi, H., Ohshiro, J., Kinjo, E, and Saito, A. (1992). Clinical study of eradicated and resistant patients to treatment with ivermectin for strongyloidiasis. Kansenshogaku Zasshi. 66,935-943. 

A patient showed a marked increase in his response to acenocoumarol when exposed to insecticides containing ivermectin and methidathion. Another patient was resistant to the effects of warfarin after very heavy exposure to a toxaphene and lindane-containing insecticide. 

The scabies mite, Sarcoptes scabiei van hominis, is becoming increasingly resistant to existing acaricidal compounds such as lindane, benzyl benzoate, permethrin, and oral ivermectin. The potential use of a 5% M. alternifolia essential oil solution to treat scabies infections was investigated in vitro. It was found to be highly effective at reducing mite survival times, and the main active component was terpinen-4-ol. However, the in vivo effectiveness was only tested on one individual, in combination with benzyl benzoate and ivermectin (Walton et al., 2004). 

In the middle of the 20th century, the synthetic development of DDT and other chlorinated hydrocarbons (C.H.), increased insecticidal activity well beyond that of most natural products. Problems arose with bioaccumulation of C.H. residues in the food chain, human fat tissue, mother s milk, as well as the development of insecticide resistance. It became obvious there were limitations to synthetic technology as well. The modification of a natural product, for example, from chrysanthemum flowers and their pyrethrum extracts (7) to pyrethroids such as allethrin, resmethrin, permethrin (2), and deltamethrin created a model in which insecticides are created from the skeleton of insecticidally active natural molecules. Thus, the avermectin, abamectin, ivermectin family of pesticides originated from compounds produced by the soil bacterium, Streptomyces avermitilis (5), and the commercially successful chloronicotinyl insecticides, though not derived from nicotine, are chemically related 4). Both pyrethroids and chloronicotinyls are currently used commercially as termiticides. We have previously provided a detailed review of natural products as pesticidal agents for control of the Formosan subterranean termites, Coptotermes formosanus Shiraki (5). 

Schwab AE, Boakye DA, Kyelem D, Prichard RK. Detection of benzimidazole resistance-associated mutations in the filarial nematode Wuch-ereria h(mcrofti and evidence for selection by albendazole and ivermectin combination treatment. Am J Trop Med Hyg 2005 73 234-8. Diawara A, Schwenkenbecher JM, Kaplan RM, Prichard RK. Molecular and biological diagnostic tests for monitoring benzimidazole resistance in human soil-transmitted helminths. Am J Trop Med Hyg 2013 88(6) 1052-61. 

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