Overview 1, 2, 3, 4, 5 Pertussis is a highly communicable, vaccine-preventable disease that affects the respiratory tract. The illness is caused by Bordetella pertussis (B. pertussis) bacteria, for which humans are the only known natural reservoir.verview 1, 2, 3, 4, 5 Pertussis is a highly communicable, vaccine-preventable disease that affects the respiratory tract. The illness is caused by Bordetella pertussis (B. pertussis) bacteria, for which humans are the only known natural reservoir.
Often, cramps. 1  a sudden, involuntary, spasmodic contraction of a muscle or group of muscles, especially of the extremities, sometimes with severe pain. 2  a piercing pain in the abdomen.
A spasm occurs when a muscle, or even a few fibres of a muscle contract involuntarily (ie without you consciously willing it). If the spasm is forceful and sustained, it becomes a cramp. A muscle cramp is thus defined as an involuntarily and forcibly contracted muscle that does not relax.This causes a visible or palpable hardening of the involved muscle. Muscle cramps can affect any skeletal muscles in the body, but are most common in muscles or muscle groups that span two joints.f the spasm is forceful and sustained, it becomes a cramp. A muscle cramp is thus defined as an involuntarily and forcibly contracted muscle that does not relax. This causes a visible or palpable hardening of the involved muscle.