BACILLUS LEPR.^ 503 
common, not only in the nasal passages of lepers and tuberculous 
individuals, but also in normal individuals as well. Karlinski's 
organism grows readily on artificial media and is in no way related 
to the leprosy bacillus. As a matter of practice, a clinical diagnosis 
of leprosy is more important than a microscopical diagnosis; the 
latter merely confirms the former. From ulcerated lepromata or from 
intact tubercidoid nodules material may be gathered and stained in 
the usual manner for the presence of acid-fast organisms. Inasmuch 
as the leprosy bacilli occur in large numbers in these tubercles it is 
best to excise a small portion of one, cut sections and stain it for 
leprosy bacilli. This will give the characteristic arrangement of the 
organisms and make the diagnosis very much more certain. Leprosy 
bacilli can be definitely distinguished from tubercle bacilli; when 
injected into guinea-pigs they do not produce lesions. 
Prophylaxis.— i/e/-erf%.— Whether leprosy is a germinal infection 
or not is not known, although the bacilli have been found both in the 
ova and in the testicles. It is suspected that children born of lei)r()Us 
parents are probably infected immediately before or shortly after birth. 
Treatment.— Since the favorable outcome of the use of chaulmoogra 
oil in leprosy in a series of 14 cases by Heiser,^ and the separation of the 
active esters, by Powell and associates and by Dean and Wrenshall,- 
the treatment of this disease has been very materially advanced. 
While it cannot as yet be stated with assurance that permanent cures 
have been obtained, at least marked improvement has been noticed, 
and it appears also to be a fact that the esters of chaulmoogra oil con- 
constitute a valuable agent in the control of the disease.'* 
Method of Dissemination.— The exact method of transmission of 
leprosy is still unknown. It is generally believed that the bacillus 
might be transmitted either by droplet infection or by direct contact. 
The organism, however, does not appear to be very infectious in 
adults at least, for experience has shown that prolonged and intimate 
association with a leper does not as a rule result in infection. 
Leprosy of Rats.— Stefansky* has reported a disease of rats which 
resembles human leprosy in a striking manner; like the disease in 
man the lesions— which consist essentially of glandular enlargement, 
subcutaneous infiltration and induration, alopecia, and frequently 
deep-seated cutaneous ulcerations— contain large numbers of acid- 
fast bacilli which resemble B. lepme both morphologically and in their 
collection in large numbers in the localized swellings. Dean^ has cor- 
roborated the obser^'ation and also found acid-fast bacilli in the nasal 
secretion of the rats. He also isolated a diphtheroid bacillus similar 
to that of Kedrowski. The disease is wide-spread among rats, being 
1 Public Health Reports, 1914, 29, 2763. 
2 Jour. Am. Chem. Sec, 1920, 42, No. 12, for literature and details. 
3 See McDonald and Dean . Public Health Reports, 1920, 35, 1959 
* Centralbl. f. Bakteriol., orig., 1903, 33, 481. 
5 Ibid., 34, 222. 
