426 TETANUS 



scopically, bacilli resembling the tetanus bacillus may be 

 recognised. Care must be taken, however, to distinguish it from 

 other thicker bacilli with oval spores placed at a short distance 

 from their extremities, such forms being common in earth, etc., 

 and also met with in contaminated wounds. It is important 

 to note that the wound through which infection has taken place 

 may be very small, in fact, may consist of a mere abrasion. 

 In some cases, especially in the tropics, it may possibly be 

 merely the bite of an insect. In many parts of the world infec- 

 tion through the umbilicus originates a high mortality from the 

 disease in newly born infants. The absence in many Bases of a 

 definite channel of infection has given rise to the term "idio- 

 pathic " tetanus. There is, however, practically no doubt that 

 all such cases are true cases of tetanus, and that in all of them 

 the cause is the b. tetani. The latter has also been found in the 

 bronchial mucous membrane in some cases of the so-called 

 rheumatic tetanus, the cause of which is usually said to be cold ; 

 infection of the intestinal mucosa may also occur. 



During the present war the clinical type of tetanus seen in 

 the wounded has been modified in consequence of the wide 

 application of the prophylactic injection of anti-tetanus serum 

 {vide infra). In the first place there has been a tendency to the 

 prolongation of the incubation period, instances where this has 

 extended to many months being not uncommon. In such cases 

 there has usually been an unhealed septic wound, often contain- 

 ing foreign bodies, and the attack of tetanus may be precipitated 

 by operative procedures ; sometimes the wound has healed and 

 tetanus has followed operation for the removal of foreign bodies 

 in the tissues. Again the disease tends to assume the type 

 seen in some animals, the muscles in the neighbourhood of the 

 wound being first affected ; local hardness and stiffness, pain, and 

 exaggeration of local reflexes have thus often been the first, and 

 sometimes the only, clinical phenomena. Such cases of tetanus 

 are also apparently more amenable to treatment with antitetanus 

 serum. 



The pathological changes found post mortem are not striking. 

 There may be haemorrhages in the muscles, which have been the 

 subject of the spasms. These are probably due to mechanical 

 causes. It is in the nervous system that we naturally look for 

 the most important lesions. Here there is ordinarily "a general 

 redness of the grey matter, and the most striking feature is the 

 occurrence of irregular patches of slight congestion which are not 

 limited particularly to grey or white matter, or to any tract of 

 the latter. These patches are usually best marked in the grey 



