Beekeepers have already observed resistance of mites to synthetic acaricides.
Bees face increasing threats and one of the most pressing is varroosis, a parasitic disease caused by Varroa destructive moth. Hives affected by high-level virus infestations are at risk of colony collapse and acute paralysis or deformed wings among hive bees in addition to a host of other problems. To protect and control mite populations, beekeepers have turned to drugs such as synthetic miticides and organic acids.
Unfortunately, these treatment options have some harmful drawbacks. Beekeepers have already observed resistance of mites to synthetic acaricides. Bees and drones have been shown to have shorter lifespans, reduced fertility, behavioral changes, and increased mortality following the use of these treatments. Additionally, certain chemicals can be found in hive products and accumulate to cause negative downstream effects for the hive.
Find a better alternative to control v. destroyer– that is, finding options that do not have adverse effects – is imperative.
Essential oils have shown promising microbial, antifungal and antiparasitic properties. Additionally, they are more environmentally friendly and are less likely to cause resistance in the mite population than some other treatment options.
A team of Italian researchers published a study in Veterinary sciences who evaluated the contact toxicity, the efficacy of fumigation and the repellent effect of origanum heracleoticum (oregano) essential oil against v. destroyer mites. Green veterinary pharmacology like this is a growing movement globally.
Using contact and fumigation methods, investigators found that oregano essential oil was effective against adult females. Varroa mites, with more favorable results due to higher exposure time and concentration. They evaluated the mortality rate 1 hour after exposure, reaching 90.9% mortality.
But the mites had no preference for wax treated with essential oil of oregano over untreated wax. The researchers indicate that for this reason, they did not observe any repellent activity of the essential oil of oregano against dust mites.
Overall, this study provided further evidence for the importance of essential oils as a possible method of controlling varroosis in bee populations. The most effective method of administering essential oils needs to be determined, so further study is needed.
Aileen Yum Chan graduated in 2022 from the University of Connecticut School of Pharmacy at Storrs.
Castagna F, Bava R, Piras C, et al. Green Veterinary Pharmacology for Bee Health and Welfare: Origanum heracleoticum L. (Lamiaceae) Essential Oil for the Control of Apis mellifera Varroatosis. veterinary science. 2022;9(3):124. doi:10.3390/vetsci9030124