The European Drosophila Stock Centre in Umea, Sweden, have a mite
infestation (Histiostoma laboratorium). We are doing all we can to get
rid of the plague and we want to warn all of you who have recieved fly
stocks from us during the last two months, to look carefully at your
stocks and to keep them in quarantine. Rapid transfers and paper discs
soaked in tetradifon might help you to get rid of the mites. Read more
about it in Drosophila, a laboratory handbook (p.1202ff) by M. Ashburner.