<prompt> Vectors for Plague transmissionX. cheopisX. astiaPulex irritansAll of the above  <response>: The commonest and the most efficient vector of plague is the rat flea , X. cheopis, but other fleas may also transmit the infection, e.g., X. astia, X. brasiliensis and Pulex irritanshuman flea. Both sexes of the flea bite and transmit the disease. Ref: Pg No:320;park Textbook ,25th Edition 