Why does tetanus shot hurt

Tetanus, commonly known as lockjaw, is a fatal disease that is caused by the bacterium clostridium tetani. The bacteria are typically found in soil, dust and manure. They enter into the human body through cuts, burns, puncture wounds and animal bites. Wound areas that are dirty, deep and contain a lot of dead tissue are more prone to tetanus infection.

The chief cause of the disease is the toxin that is produced when the tetanus bacteria multiply rapidly. The toxin affects the region where the nerve interacts with the muscle. This site is called the neuromuscular junction. Due to the presence of the toxin, the chemical signal that the nerve sends to the muscle is amplified. As the result, the muscle remains contracted for a long duration of time. These muscle spasms may either be localized affecting neck, stomach, abdomen and extremities or generalized, where muscle spasms occur throughout the body. Lockjaw occurs when the muscle spasms take place in the face and neck. Due to the spasms, the person is unable to open his jaws. This is the most common symptom of the disease. Tetanus is not a contagious disease, and it is fatal only in 30 percent of the reported cases. The incubation period normally ranges between 2-days to 2-months.

Immunization is the best way to prevent the occurrence of the disease. The vaccine for the prevention of tetanus is a toxoid, that is, it produces the bacteria to provide protection against the toxin. All children between the age of 2 months and 5 years, receive a series of 5 DTaP vaccinations. Thereafter, booster vaccination is administered when the child is 11 years of age. Follow-up booster dose is recommended every 10 years. In addition to providing protection against tetanus, this vaccine also fights against diphtheria and pertussis.

Tetanus shot is characterized by pain, swelling, soreness, tenderness and redness at the site where the injection has been administered. Tetanus bacteria thrive in that environment where there little or no oxygen. If the wound is superficial, the bacteria do not grow rapidly because of the presence of oxygen. However, if the would is deep, the bacteria replicate quickly because of the absence of oxygen at the site of injury.

When the tetanus shot is administered, clostridium tetani bacteria are produced, which persuade the body to release antibodies. These antibodies act against the tetanus toxin. They are also responsible for the pain after tetanus shot. The more the number of bacteria in the body, the greater will be the intensity of the pain. Pain killers like Ibuprofen and hot fomentation are the best remedies to alleviate pain. After a day or two, the pain will automatically subside.