What is the vector for Lyme Disease?

Lyme disease is transmitted primarily by the black-legged tick, scientifically known as Ixodes scapularis. This tick is responsible for carrying the bacterium Borrelia burgdorferi, which causes Lyme disease. The habitat of Ixodes scapularis often includes wooded and grassy areas, where it can feed on hosts like deer and small mammals, facilitating the spread of the disease to humans.

The other options listed do not serve as vectors for Lyme disease. For instance, Xenopsylla cheopis is better known as the oriental rat flea, which is associated with the transmission of diseases like bubonic plague and murine typhus, but not Lyme disease. Dermacenter variabilis, also known as the American dog tick, can transmit other illnesses, such as Rocky Mountain spotted fever, but is not a primary vector for Lyme disease. Triatoma sanguisuga, commonly referred to as the kissing bug, is known for its role in transmitting Chagas disease, not Lyme disease.

Thus, Ixodes scapularis is the correct answer, as it is the only tick directly involved in the transmission of Lyme disease to humans.