Effect of age of worker honey bees (Apis mellifera) on tracheal mite (Acarapis woodi) infestation

The susceptibility of worker honey bees, Apis mellifera L., as a function of age, to infestation by tracheal mites, Acarapis woodi Rennie, was investigated. Bees < 24 h old were infested most frequently, and the frequency of infestation declined precipitously thereafter. Bees > 4 days old were rarely infested in colonies during active brood rearing. Only 2 of 255 bees > 8 days old, and 1 of 246 bees > 16 days old, became infested. Most of the eggs found in bees > 3 weeks old apparently were produced by the progeny of the original infestation.