Lyme Disease - Causes

A tick passes through three stages of development: larva, nymph, and adult. The larva is an immature form of the tick. It hatches from eggs laid on the ground in summer. Larvae attach themselves to small animals and birds and feed on their blood. At this point, the larvae are no threat to humans.

Eventually, larvae develop into nymphs. Nymphs feed off humans. It is at this stage of a tick's life that it is the greatest threat. A nymph can transmit Lyme disease if it bites a human. A nymph is too small to be seen easily seen, and as a result, people may be bitten without realizing it.

Adult ticks feed off humans, mice, and deer. They are sometimes called deer ticks. They can still transmit Lyme disease, but they are larger and easier to see. They are thus less of a threat to humans, who can pick them off quite easily.

The Bb bacterium spreads quickly once it reaches the human bloodstream. It can usually be found in the cerebrospinal fluid (CSF) only twelve hours after a tick bite. Cerebrospinal fluid is the fluid found in the spinal column.