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.
The main cause of neck pain is tension. During periods of intense anxiety, your muscles tense up dramatically. Muscle tension tightens the muscles, especially in the shoulders, back, and neck. The more anxiety you experience, the more your tension may cause significant pain and discomfort. A related issue comes from the mindset of those with anxiety. Many people get muscle tension in their neck during times of stress.
What causes it? The most common causes of neck cramps or spasms are torticollis, sprain or strain, and muscle spasm. Within all the people who go to their doctor with neck cramps or spasms, 67% report having neck pain, 46% report having back pain, and 33% report having shoulder cramps or spasms.