Externally they have ticks, fleas and lice. Their vectors are mostly hematophagic arthropods such as fleas, lice, ticks, and mosquitoes. Fleas and lice can hide in seams. Biological vectors are usually, though not exclusively, arthropods, such as mosquitoes, ticks, fleas and lice. In field environments, soldiers are susceptible to infestation of lice, ticks, and fleas. Vector transmission occurs most often from insect bites from mosquitoes, flies, fleas, and ticks. Fleas and ticks are common causes of physical irritation. Flies, fleas, and mosquitoes can carry the virus between rabbits. Phenothrin is primarily used to kill fleas and ticks. Insecticides can protect animals from illnesses that can be caused by parasites such as fleas. Red foxes are not readily prone to infestation with fleas. Boric acid is used as an insecticide, notably against ants, fleas, and cockroaches. It is caused by drinking water contaminated by water fleas infected with guinea-worm larvae. Bacterial diseases carried by fleas include murine or endemic typhus and bubonic plague. Bubonic plague is mainly spread by infected fleas from small animals.