Typhus Fever and Pediculidce 
239 
of the second generation were placed on a normal rhesus monkey. 
The experimenters were unable to keep the monkey under very 
close observation during the following three or four weeks, but from 
the fact that he proved resistant to a subsequent immunity test 
they concluded that he probably owed this immunity to infection 
by these lice of the second generation. 
Anderson and Goldberger (19126) object that due consideration 
was not given to the possibility of a variable susceptibility of the 
monkey to typhus. Their similar experiment was “frankly nega¬ 
tive.” 
Prophylaxis against typhus fever is, therefore, primarily a ques¬ 
tion of vermin extermination. A brief article by Dr. Goldberger 
(1914) so clearly shows the practical application of his work and that 
of the other investigators of the subject, that we abstract from it 
the following account: 
“ In general terms it may be stated that association with a case of 
typhus fever in the absence of the transmitting insect is no more 
dangerous than is association with a case of yellow fever in the 
absence of the yellow fever mosquito. Danger threatens only when 
the insect appears on the scene.” 
“We may say, therefore, that to prevent infection of the indi¬ 
vidual it is necessary for him only to avoid being bitten by the louse. 
In theory this may readily be done, for we know that the body louse 
infests and attaches itself almost entirely to the body linen, and that 
boiling kills this insect and its eggs. Individual prophylaxis is 
based essentially, therefore, on the avoidance of contact with indi¬ 
viduals likely to harbor lice. Practically, however, this is not 
always as easy as it may seem, especially under the conditions of 
such intimate association as is imposed by urban life. Particularly 
is this the case in places such as some ol the large Mexican cities, 
where a large proportion of the population harbors this vermin. 
Under such circumstances it is well to avoid crowds or crowded places, 
such as public markets, crowded streets, or public assemblies at 
which the ‘peon’ gathers.” 
“Community prophylaxis efficiently and intelligently carried out 
is, from a certain point of view, probably easier and more effective 
in protecting the individual than is the individual’s own effort to 
guard himself. Typhus emphasizes, perhaps better than any other 
disease, the fact that fundamentally, sanitation and health are 
economic problems. In proportion as the economic condition of the 
masses has improved — that is, in proportion as they could afford 
