Warning signals of tetanus should be kept in mind, because the disease could occur even when the injury is minor and totally forgotten. In that case, probably, the injury was so minimal that the patient may not have cared to take a booster dose of the vaccination, or may have remained entirely unimmunized. In such cases, the disease appears like a bolt from the blue. However, if the patient is aware of the early symptoms and signs of the disease, he is likely to immediately report to the physician, and the disease can be treated fully with the availability of effective antitetanus serum (ATS). But, if the patient is late and comes with a full-fledged attack of tetanus, survival may not be possible, as firstly, antitetanus serum (ATS) may not prove effective in neutralizing the large amount of tetanus toxin already present in the blood, and secondly, the patient is likely to die of the various fatal complications of the disease in its advanced stage.



Hence, the importance of awareness regarding the warning signals of this disease is vital, so that the patient reaches the doctor quickly, and the treatment is started instantaneously.

The first and the foremost symptom of tetanus is difficulty in opening the mouth (trismus) due to the spasm of the muscles of mastication. Hence, the disease is commonly called 'lockjaw'. It may be noted that this difficulty in opening the mouth is painless, and if one tries to open the mouth, the spasm of the muscles that closes the jaw will increase and, therefore, the patient may not be able to open his mouth widely, howsoever, he may try and, in some cases both the jaws are tightly closed and the teeth clenched.

'Lockjaw' is the earliest characteristic symptom of the disease, and the patient should not delay even if the difficulty in opening the mouth is slight, particularly when there is a history of injury in the recent past.

The incubation period of tetanus, i.e., the period between the injury and the occurrence of lockjaw, is on the average, 1-3 weeks. The disease may manifest itself within 2-3 days in the case of injury of the face (being near to the central nervous system). On the other hand, the incubation period may be much longer, say even months, if the tetanus spores remain dormant in some of the wounds, where the conditions are not favorable for their germination.

However, lockjaw or difficulty in opening the mouth should not frighten the person; it may also occur as a result of acute inflammation/ sepsis of the tonsils and its surrounding areas, including dental conditions, especially impacted tooth; but in such cases, the condition is quite painful, and the patient usually points out the area of pain.

Difficulty in opening the mouth may be accompanied with difficulty in swallowing, with or without some change in the voice, due to the spasm of the muscles for swallowing, as well as of the larynx. Soon stiffness of the neck, tightness of the chest and rigidity of the abdominal wall may take place, due to the spasm of the muscles of the neck, chest and abdomen respectively. The warning signals of tetanus may be summarized in its usual order of sequence as follows:

(i) Lockjaw, with or without recent or past history of injury anywhere on the body.

(ii) Difficulty in swallowing and/or change in voice.

(iii) Stiffness of the neck, followed by tightness of the chest and rigidity of the abdominal wall.