Ectoparasites and Pathogens Associated with Rats

Rat ectoparasites are a health threat! It’s well known that rats and other rodents can have pathogens that affect public health. A Zoonotic disease is one that is transferred between wild or even domestic animals and humans. The ectoparasites like fleas and mites, which are pests that live on the outside of rats, often deliver pathogens from the rodents to humans and this is especially concerning in highly populated urban areas. Ectoparasites will weaken the immune system of rodents, therefore rendering them more susceptible to illness. Ectoparasites on Rats in Orange County A survey was conducted on Roof rats in Orange County to study ectoparasites and associated pathogens (from fleas) in order to assess risk to public health. The same study collected the following ectoparasites from 150 rats throughout the county. Tropical rat mite (Ornithonyssus bacoti) Spiny rat mite (Laelaps echidnina and Laelaps nuttali) Oriental rat flea (Xenopsylla cheopis) Spined rat louse (Polyplax spinulosa) Most rats collected had an average of 4 fleas per rat, while rats from one of the residential area had about 25 fleas per rat. All flea samples contained Bartonella, a bacterium responsible for several diseases affecting humans, like cat scratch disease, endocarditis, and trench fever. Rats will impact the lives of children and adults so rat control is essential to helping protect the public health. Preventing a rat’s access to food, water and shelter through exclusion is essential to helping reduce and/or eliminate high rat populations but baiting of rats is often part of an effective control plan. These control activities can serve to decrease both rat and ectoparasite populations that effect humans and their pets. Two good examples of how these extoparasites can effect humans and the negative impact the have are the Rat and Mite problems at one school in the Saddleback School district and one at Villa Park Elementary School.