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.
Causes of Neck Pain. Strained Neck Muscles. In teens, new neck pain is mostly from stretched neck muscles muscle overuse. Common triggers are sleeping in an awkward position or fixing something on the ceiling. Reading in bed or working on a computer for hours can trigger neck pain.