18.104.22.168.1. Manual infestation
1. Using recently capped brood i.e. within 6 hours (see section ‘Obtaining brood and adults of known age’ of the BEEBOOK paper on miscellaneous methods (Human et al., 2013)) make a small hole in the side of the capping.
2. Introduce the mite using a fine wetted paint brush.
3. Close and reseal the hole by pushing the capping down.
Workers will seal the hole when the frame is reintroduced in the colony. Using melted wax to prevent the mite escaping is not recommended since it could damage the fragile larva.
4. Mark the location of the cell on a transparent sheet placed above the comb.
This method needs practice. From an initial 20 % acceptance of artificially infested brood, one can rapidly reach 80 %. This rate is however variable according to colony and experimenter. The success rate can be checked by removing frame after few hours and verifying the status of the cell. Important: bees covering the combs used for artificial transfers must be carefully removed with a brush and not by shaking, which could damage pupae and mites. An opened and empty marked cell means that the workers removed the larva and the mite. Workers might also discard the old capping and reseal the cell without removing the larva. This can be recognised by a fresh capping deprived of cocoon layer. In this case the mite might have escaped or have been removed before resealing.