New wet sieving method for isolating house dust mites

Abstract

A new wet sieving method for isolating house dust mites from dust was developed by modifying the Furumizo method. In five successive sievings of samples collected by vacuum cleaners, the average proportion of mites isolated in the first three sievings to the total number was 98.4% (ranged from 89.5 to 100.0%) for live mites and 98.7% (90.8-100.0%) for dead mites. Recovery rates of 100 live Dermatophagoides farinae marked with Rhodamin B in each of four 500mg dust samples ranged from 84-95% by three times of sieving; and of dead ones, from 91-98%. This new method was superior to the Darling solution centrifugation method, as far as the isolation efficiency was concerned, when these two methods were compared among five samples each of 0.5g dust.