37 
man on vegetables seems remote, in view of the fact that no other 
cases occurred. 
The man had eaten no shellfish. So these, as a possible factor, 
can be excluded. 
That no other cases developed in the ward, where there were about 
thirty other demented cases — most of whom were very careless vdth 
their excreta — and the fact that the examination of the stools and 
urine of all the newcomers in the ward were negative for the typhoid 
bacillus, argues strongly against the view that the infection may 
have been caused by a bacillus carrier. 
It is evident that all the known methods of introduction of recent 
infection to this man seem remotely applicable. A possibility of a 
prolonged incubation period in this case has to be considered. 
Davies and Hall® report an instance of a bacillus carrier who, in the 
course of three years, apparently caused three outbreaks of typhoid 
fever, and then herself had an attack of fever which the authors con- 
sidered clinical typhoid. 
If the man contracted the infection before he came to the insti- 
tution he had to do so two years before his onset of definite symp- 
toms. If he were a bacillus carrier during this time some of the 
other inmates in the ward very probably, but of course not neces- 
sarily, would have been infected. 
The solution of the mystery surrounding the causation of this 
case probably would throw much light on the problem of the causa- 
tion of typhoid fever generally. 
CASE AND DEATH RATES FOR CALENDAR YEARS 1908, 1907, AND 
1906. 
The total number of cases of typhoid fever in the District of Colum- 
bia reported to the health officer during the calendar year 1908 was 
936, as against 945 in 1907 and 1,126 in 1906. Thus the typhoid- 
fever morbidity rate in the District of Columbia for the calendar 
year 1908 was 2.75 per 1,000 of population, or 1 person in every 
362, as against 2.87 per 1,000 in 1907 and 3.45 per 1,000 in 1906. 
Although the morbidity rate was slightly lower in 1908 than in 
1907, the death rate was slightly higher. 
The number of deaths from typhoid fever in the District of Colum- 
bia in 1908 was 124, being a death rate of 36.53 per 100,000 of popu- 
lation, as against 34.5 for 1907 and 49.3 for 1906. 
Of the 124 deaths in 1908, 88 were among whites and 36 among 
negroes, giving a death rate among whites of 36.37 per 100,000 and 
among colored of 36.92 per 100,000. 
a Lancet, Nov. 28, 1908, p. 1585. 
