Which of the following are vectors for plague?

• A. Ticks
• B. Rodents
• C. Rodent fleas
• D. Cats

Answer: (C)

Plague spreads through a specific transmission route where a biting insect carries the bacteria from an infected animal to a new host. Rodent fleas are the classic vector because they pick up Yersinia pestis when feeding on an infected rodent, then transmit it to humans or other animals during subsequent bites. The bacteria multiply in the flea and can block its gut, causing regurgitation of the pathogen into the bite site. Rodents act as reservoir hosts, keeping the bacterium in the environment, but they are not the vectors themselves. Ticks are not the typical vectors for plague, and while cats can become infected and may transmit in certain scenarios, the well-established transmission path between humans and animal hosts is via rodent fleas.