What parasite transmits Lyme disease?

• A. Dirofilaria immitis
• B. Heartworm
• C. Lice
• D. Tick

Answer: (D)

Lyme disease is spread by ticks. Ticks act as vectors, carrying Borrelia burgdorferi, the bacteria that cause Lyme. When a tick bites and feeds, the bacteria can be transmitted to the host, typically after the tick has been attached for about a day or two. This is why removing ticks promptly reduces risk. Other listed organisms don’t transmit Lyme disease: heartworm is a nematode transmitted by mosquitoes, and lice are not vectors for this infection. So the parasite that transmits Lyme disease is the tick.