Varroatosis is one of the most feared bee diseases in Europe and regularly leads to large losses. The disease is caused by the Varroa destructor, a parasite damaging both adult bees and bee brood. An attack of Varroatosis leads to deformity (e.g., deformed wing virus), crippling and death of the brood. The disease must be treated by law; one method of doing so is to use authorised varroacides.
Many beekeepers decide to use organic acids such as lactic acid, oxalic acid or formic acid. These acids or their salts are found naturally in the metabolism of plants and animals, or directly in some varieties of honey. Organic acids are also used after the final honey harvest in the autumn and winter, and prevent critical amounts of parasites from remaining that would otherwise accumulate, above all, in the beeswax. A concentration in the wax to this effect would ultimately damage the honey too. In contrast to traditional treatment methods, the acids are not liposoluble, meaning that an accumulation in the wax is not possible. This method is recommended by some ministries and beekeeping institutes.