Fleas
Fleas can be vectors of disease or may transmit parasitic worms. The most serious infection which they can spread is bubonic plague, transmitted to man by rodent fleas (Xenopsylla cheopis) which carry the causative bacillus from infected rats. In the past rodent fleas have been responsible for serious epidemics of the disease, notably the Great Plague of London in 1665. Rodent fleas may also carry murine typhus and, because of their readiness to attack humans as well as rats, are probably the major flea vector of disease. The Dog flea is an intermediate host of the Dog tapeworm (Dipylidium caninum), whose vertebrate host is usually the dog (occasionally the cat) but which can sometimes be transmitted to man. in Europe fleas are not generally responsible for the transmission of disease. However, they are still objectionable because of the bites they inflict and the deep-rooted social stigma attached to humans with flea infestations.
