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 Tight Muscles In Neck And Shoulders. 1  Sporting activity: people who play sports such as tennis, badminton or athletes are susceptible to muscular strain and injury. Sport activities where the use of neck and shoulder muscle is more can lead to pulling of such muscles. Overstretching can cause spasm and restricted movement of neck and shoulder. Poor posture: neck and shoulder tightness is also a reason of poor posture. Sitting in front of a computer for long hours can put stretch and strain on muscles of shoulder and neck.