Active and Passive Immunity. Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response. Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen.
Lower back tightness can cause muscle twitching, pain and reduced range of motion. Lower back muscle tightness is the cause of a muscle spasm. This can be brought on by a strain, overuse or muscle weakness, according to BetterMedicine.com.
Injury is the most common cause of back pain. Improperly lifting heavy objects can cause back cramps. A hot bath can help to relax the muscles and eliminate back cramps. A heating pad can help relax muscles and eliminate back cramps.The muscles of the back. Back cramps may accompany menstrual cramps in women. Back cramps can be caused by poor posture.mproperly lifting heavy objects can cause back cramps. A hot bath can help to relax the muscles and eliminate back cramps. A heating pad can help relax muscles and eliminate back cramps. The muscles of the back.