Which disease is historically associated with flea-borne transmission?

• A. Malaria
• B. Lyme Disease
• C. Typhus
• D. Bubonic Plague

Answer: (D)

Flea-borne transmission means a disease is spread to humans by the bite of a flea. The disease most famously linked to this mode of transmission is the bubonic plague, caused by Yersinia pestis, carried by rat fleas. Fleas become infected after feeding on an infected rat and then pass bacteria to humans through their bite, which sparked devastating outbreaks such as the Black Death in medieval times.

Malaria is transmitted by mosquitoes, not fleas. Lyme disease is carried by ticks. Typhus is typically spread by body lice, though there are flea-associated forms of typhus as well; historically, the classic flea-borne, highly documented disease is bubonic plague.