Which vector is responsible for transmitting Rocky Mountain spotted fever?

The vector responsible for transmitting Rocky Mountain spotted fever is the deer tick, specifically the Ixodes scapularis species in the eastern United States and Ixodes pacificus in the western United States. These ticks are capable of harboring the bacterium Rickettsia rickettsii, which causes this disease.

Transmission occurs when an infected tick bites a human. As the tick feeds on the host's blood, the bacterium can be transferred, leading to the symptoms of Rocky Mountain spotted fever. This disease is characterized by fever, rash, and in severe cases, can lead to serious complications.

The other options listed do not serve as vectors for this particular disease. The human body louse is known for transmitting lice-borne diseases but is not involved in the transmission of Rickettsia rickettsii. Rat fleas primarily transmit diseases like plague and can carry other pathogens but are not responsible for Rocky Mountain spotted fever. Mosquitoes are vectors for a different set of diseases such as malaria and dengue fever but do not play a role in the transmission of this rickettsial infection.

Therefore, the correct identification of the deer tick as the responsible vector is crucial for understanding the ecology of Rocky Mountain spotted fever and how