Medycyna Wet. 66 (7), 475-479, 2010
Adam Dzierżawski, Wojciech Cybulski
Evaluation of the efficacy of Apiwarol AS
Varroasis has been treated with numerous different substances, including amitraz, which has been used since 1981. In 1984, Apiwarol AS – a drug in the form of a flammable tablet containing 12.5 mg of amitraz - was registered. The active substance, diffusing with smoke particles into the beehive, paralyzes Varroa destructor within an hour. Amitraz is also used as a component of other drugs, e.g. Biowar, which has the form of plastic strips containing 400 mg of the active substance. Unlike in the case of Apiwarol AS, amitraz diffuses slowly, reaching a therapeutic level in the beehive in 6 – 8 weeks. Over 25 years of observation on the combating of varroasis indicate that the parasites may develop resistance against amitraz, which has usually been observed after treatment with strips. Presumably, a long exposure to the substance released from the strip is more likely to produce resistance than fumigation with Apiwarol AS over a relatively short time. However, some reports of a reduced efficacy of fumigations have also been made. In these cases the efficacy of the drug may have been reduced by such factors as inappropriate application; season of the year and time of the day when the drug was used as well as the number of fumigations. On the other hand, a comparison of results for the years 1981 1985, 1986 - 2000 and 2001 – 2009, presented in numerous studies, indicates that there were no statistically significant (P≤0.05) differences in the efficacy of combating V. destructor with amitraz in these periods, which was 93.6±3.73 %, 95.4±3.43 % and 93.2±6.59 %, respectively. Nevertheless, further laboratory and field investigations are required to assess the ability of the parasite to develop resistance against Apiwarol AS.
Key words: amitraz, Apiwarol AS, varroasis, treatment, efficacy