All ticks (including deer ticks, dog ticks, Lone star ticks, etc.) come in small, medium and large sizes. The smallest size, called larvae, are nearly microscopic. The middle stage, called nymphs, are medium sized although most people would call them tiny. Nymphs of all ticks are about the size of a pinhead in their unfed state.

Then there are the large size or adult stage ticks. Even the adult stage of Blacklegged ticks (aka deer ticks) that transmit Lyme disease are relatively large. In the northeastern United States, the most common “large” tick likely to bite dogs, cats, horses, and humans in the Fall and Winter months is the Blacklegged tick, and it can transmit disease-causing agents including Lyme bacteria. Typically, about 50% of adult Blacklegged ticks are infected with Lyme bacteria.