If you don’t treat a colony that is infested with Varroa mites effectively, you are condemning it to certain death, within a year in many cases.
These mites weaken the bees by feeding off their haemolymph (blood). Bees become far less resistant to other diseases, their lifetime is greatly shortened and their wings become atrophied. Fewer forager bees can fly to find pollen and nectar to feed larvae in the brood, and weakened, their return flight to the hive becomes more and more difficult. The colony produces less and less honey and becomes unable to feed the new bees, which causes the weakness (in spite of the laying activity of the queen) then the colony collapses.
Moreover, it has been proven that the higher the rate of infestation, the shorter the duration of life of honey bees. That is a real issue for wintering bees that are infested during their development and not able to go through winter and take part in colony development in spring.
Treating against Varroa mites is a matter of bees and colony survival. The goal is to lower the infestation rate to a threshold that can be sustainable for colony development and survival in winter.
Varroa destructor is a real plague for the honey bees and beekeepers in a majority of countries all over the world. Its control is a matter of global concern of the worldwide beekeeping industry.
Apivar strips are made of two components:
Amitraz is an acaricide. It does not kill mites directly, but is rather considered as a sub-lethal miticide with an original mode of action from neurotoxicity type, different from other current Varroacides. Acting on the synaptic transmission of mites, it leads to constant excitation and paralysis, followed by mite drop from the bee’s back. Secondarily, Varroa dies due to starvation as a result of this paralysis. Amitraz acts by contact only.
A plastic polymer specially chosen for its rigidity and to allow a slow and continuous release of amitraz during many weeks.
Apivar strip has been designed to release the active ingredient, from the opening of the pack, as soon as it is put into the hive. Amitraz is available on the surface of the strips for the bees that come in contact. The active ingredient is spread into the colony from one bee to another by contact. After a short period of time, amitraz is hydrolyzed and disappears from the hive.
Mode of action into the hive
1. Amitraz is available at the surface of the strip in the hive
2. Honey bees in contact with the strips pick up the active ingredient (no diffusion into the hive by evaporation)
3. By contact, honey bees can transfer the amitraz within the colony
4. Amitraz is quickly hydrolyzed and disappears from the hive. (cf FAQ residues)
Merrington, O (1990). Bibliography on the Use of Amitraz for Varroa Control in Bees (Apis spp.) (1979-1989). Cambridge, UK, Cambridge Animal and Public Health Ltd. 36pp.
Spread of amitraz into the colony is the result of the contact between the honey bees and the strips. As a consequence, this diffusion is not directly linked to the external temperature. This mode of action is different from other devices used to treat against Varroa such as thymol-based products whose diffusion by vaporization changes in relation to the hive’s atmosphere. This diffusion is blocked at a low temperature or dangerously increased at a very high temperature.
Regarding amitraz, temperature has no effect on the product itself. Nevertheless, we can consider that at low temperature, activity of bees is lowered and contacts with the strips can decrease.
You may use the product all year round, but as an additional safety factor for the good image of honey, it is recommended to not use Apivar when the honey supers are present:
- After harvesting, towards the mid or end of the Summer – “Autumn Treatment”
- Before the nectar collecting period in the Spring – “Spring Treatment”
Treatment after the last usable honey flow – Autumn Treatment.
The aim of the autumn treatment is to decontaminate the colony before winter bees are produced and is considered the most important treatment in most beekeeping systems to prepare the colony for a good wintering, in addition with correct feeding when needed.
It should be initiated as soon as honey supers are removed
- when the nurses of winter bees are developing so that their breeding capacities can be maximized.
- before the parasites have had time to harm the colony
The aim of the spring treatment, with the removal of the strips before adding the honey supers, is to decrease the mite populations before honey collection and to be sure that there will be no risk of colony collapse during the season up to the Autumn treatment and to maximise honey yield.
Varroa mites can be most quickly and easily eliminated when the least amount of brood is present.
The recommended dosage is 2 strips per brood chamber (or 1 strip per 5 frames of bees).
Apivar was tested on the basis of a precise dosage and specific use directions, therefore these should be followed to obtain the best performance.
Under-dosage may lead to poor efficacy and be critical for the colony survival until the next varroa treatment.
An excessively low concentration may cause the parasites to become resistant to the active ingredient. That could be the case if only one strip was inserted, if old strips were re-used or if strips were not removed after the treatment period.
There is no contraindication to feed and treat at the same time. Apivar does not effect feeding. On the contrary, it can be easily thought that the two activities are synergistic to fight against Varroa mite:
- Feeding increases activity in the colony and probably the contact of bees with the Apivar strips. So it can be considered as a good way to increase the speed of decontamination.
- Feeding has the same goal as Apivar treatment, to reinforce the colony for the winter season. As a consequence feeding and treating at the same time can be regarded as good preparation for the wintering period.
From a regulatory point of view, Apivar can be used all year round. Nevertheless, in accordance with good beekeeping practice, we recommend to treat when honey supers are not present. This would be the best way to convey a good image for honey as a natural product. As a consequence, strips should be removed before the main nectar-collecting period in the spring and can be placed into the hive after harvesting during summer.
It is recommended to treat when there is some brood in the colony and that is one of the major assets of a long-release treatment such as Apivar in treating against Varroa.
The strips release amitraz for many weeks. As a consequence, treatment is effective for several reproduction cycles of the Varroa mite and can be more effective for decontamination of the colony.
It is very important to position the strips in an area of high activity and nearest to the Varroa breeding area (in the brood).
Nevertheless, when there is no brood in the hive, treatment is also effective.
As Apivar is a medicine, you should read and follow the directions of use.
- Positioning of the strips.
Apivar works by contact only. It is therefore very important to position your strips in an area of high bee activity, and nearest to the Varroa breeding area in the brood area.
This ensures that many bees will be in regular contact with the strips in order to give effective distribution of the Amitraz throughout the hive.
Ideal positioning is to hang up each strip between 2 frames inside the brood area with a minimum distance of 2 frames between strips.
- Respect the recommended dosage.
The recommended dosage is 2 strips per brood chamber. Apivar was tested on the basis of a precise dosage and specific direction for use. The recommended dose on the label should be followed to obtain the best performance.
- Treating all the hives at the same time:
Adult Varroa mites attach themselves to adult bees. They spread when hives are robbed, when drones move from one hive to another, and even, according to some researchers, when pollen is gathered through foraging bees. Hive member exchanges, meeting of colonies, artificial swarming and even bee shipments and purchase may infest a hive that has previously been healthy. To avoid this, check your hives regularly and treat all of them if you see any infestation.
- Checking strips position after a few weeks.
Sometimes, during the Autumn treatment, the brood area can slowly move. As a consequence, a few weeks after the beginning of the treatment, the strips of Apivar are no longer amongst the brood. This situation can decrease the efficacy of the treatment by lowering the number of contacts between bees and strips.
It is recommended to check the position and to correct if necessary. In this case it can be appropriate to lengthen the treatment by 2 additional weeks.
- Remove the strips at the end of treatment.
Strips should be removed at the end of the treatment for 2 main reasons:
– At the end of treatment, after a long releasing process, the quantity of amitraz released by the strips is lower. This creates favourable conditions for resistance development.
– Apivar strips are not biodegradable. Product should be disposed of in a registered local body landfill (i.e. local rubbish collection).
- Strips should not be reused.
This is very rare. Our recommendation will be to remove the propolis from the surface as it prevents bees from having real contact with the strips and lowers the diffusion of amitraz.
Apivar packs are sealed under vacuum to ensure a good preservation of the strips and the best quality. So, to guarantee a high concentration of amitraz, strips have to be used as soon as possible after opening.
After removal the strips should be disposed of in a registered local body landfill (i.e. local rubbish collection).
In the EU where it has been developed, Apivar is classed as a veterinary medicine and is subject to the medicine regulations. As a consequence, Apivar benefits from a full market authorization dossier with efficacy data that shows its efficacy to reduce Varroa mite infestation.
Since it has been authorized, many trials have been carried out on a regular basis to monitor its efficacy. For example, in France, where Apivar is authorized and used on a large scale since 1995, Veto-pharma takes part every year in an efficacy study. The efficacy of Apivar remains very high despite a very intensive and repeated use for many years in a lot of countries worldwide.
Trials have also been conducted in the US and Turkey in 2009, and in Bulgaria in 2011. All the results are consistent and show a constant efficacy.
The French laboratory of ANSES in Sofia Antipolis, is the reference lab for the European Union for honey bee health. It has conducted a residue trial in 2007 whose results are consistent to previous ones:
- No residue of Amitraz was detected in honey after 10 weeks of treatment, regardless of the date of sampling. This is due to the instability of the active ingredient in an acid environment. Other studies have also proved that the amitraz is fully degraded after 10 days in honey.
- No residue of amitraz in wax after 24h after the removal of the strips.
This publication also studied residues of coumaphos in honey and wax with less satisfactory results.
Other studies concluded that quantities of residues of amitraz or its main metabolites in honey are always under the MRL.
Ref: Martel A.C. et al, Acaricide residues in honey and wax after treatment of honey bee colonies with Apivar or Asuntol 50, Apidologie (2007), 38, 2002, 534-544
Ref : R.M. Goodwin et al, Residues of amitraz in wax honey and propolis after using Apivar, 2002
Apivar is authorized in several countries thanks to a complete Market Authorization Dossier that includes safety data.
Two types of toxicity have been assessed:
- Toxicity for the bees.
A study applying Amitraz at a dosage 5 times more than that recommended, shows no effect on honey bees, queens and brood.
- Toxicity for human beings.
This safety is controlled with the MRL system that fixed a maximum limit of residues that are allowed into products dedicated to human consumption. Many residues studies have proved that the residues of amitraz and its main residue are always lower than this threshold which is 200 ppm (200 mg per ton of honey).
This good situation is due to the high instability of amitraz and its quick hydrolysis.
As a consequence, it can be said that amitraz is safe when it is used in accordance with recommendations (dosage, treatment duration…)
Ref: Martel A.C. et al, Acaricide residues in honey and wax after treatment of honey bee colonies with Apivar or Asuntol 50, Apidologie (2207), 38, 2002, 534-544
On the contrary pyrethroids (like fluvalinate) are more stable in wax. Some studies show that the level of residues of this product is higher for a longer time than those of amitraz’s. The risk of residues in honey is more likely with these type of actives.
Ref: S. BOGDANOV et al, ACARICIDE RESIDUES IN BEESWAX AND HONEY, (1997)
Ref: K. WALLNER, Varroacides and their residues in bee products, Apidologies 30 (1999) 235-248
Apivar is the result of a unique technology allowing the continuous liberation of a little dose of the amitraz for a long duration. To cover many varroa mite life cycles, it is important to leave the strips unmoved for several weeks. This long-acting treatment does not lead to an accumulation of residues. Amitraz is very sensitive to hydrolysis which means that it is very quickly destroyed after liberation. Many studies have shown that there is no more residue after 24h in wax and honey.
Amitraz is destroyed as the treatment goes along.
Nevertheless, it is important to remove the strips at the end of the treatment to avoid the continuous liberation of amitraz at very low dosage, too weak to be effective but probably high enough to select resistances. Forgetting the strips in the beehive for all of the wintering period could probably be responsible for the hypothetic emergence of resistance.
It has been recognised for many years that amitraz is very effective for the control of varroa mite infestation in the colonies. Nevertheless, efficacy and security for both humans and bees are only provided by a restricted use of the active ingredient.
The use of Taktic in the apiary is very far from Apivar guarantees. Taktic is a short acting product and as a consequence only kills phoretic varroa present at the moment of the application with no control of the residues and the quantity of actives inhaled by the beekeepers. New generations of bees will be contaminated as soon as they emerge from their cells. As a consequence, this illegal treatment presents very low effect when there is brood in the colony and is responsible for high risks to honey bees and human health.
On the other hand, Apivar is authorised as a drug which delivers a controlled and continuous amount of active during many varroa lifecycles allowing elimination of most of the varroa in the beehive. Moreover, the residues are known and always lower than the regulatory threshold (Maximum Residue Limit) defined for this active.
Apivar is not only effective but safe and helps beekeepers to increase the quality image of the honey.