8 The Philippine Journal of Science 1915 
did the man acquire a new and more virulent infection which 
caused him to sicken? 
Apparently healthy persons in quarantined barracks in Bilibid 
Prison, from which carriers were being carefully sought out 
and removed by means of bacteriological examinations made 
every other day, have produced cases in from two- to three-day 
up to twelve- and thirteen-day intervals. This is suggestive of 
persons being able to harbor an infection which is undetectable 
by present methods, or else of a much longer incubation period 
than has previously been accepted. 
One instance is reported of a man who was treated as a case of 
cholera at San Lazaro Hospital in 1913 and this year was found 
to be a cholera carrier and sent there for detention. The ques- 
tion at once presents itself as to whether or not he might per- 
haps have been a host for the cholera germ since his previous 
sickness, and thus be representative of a class whose existence 
in these Islands may reasonably be inferred from the practically 
annual recurrences of this disease and by which the gaps be- 
tween one outbreak and another may very possibly be bridged 
over. 
Treatment to free the intestines of cholera carriers of cholera 
vibrios seems to have been of little value. It will be discussed 
in another paper at this meeting. It is worthy of note that 4 
cases of cholera, 1 case fatal, occurred in carriers who had for 
some time been receiving salol in 0.6 gram doses twice daily in 
the effort to hasten the disappearance of cholera germs through 
the use of intestinal antiseptics. 
As to the duration of the period in which the average cholera 
carrier spontaneously cleared up, there seemed to be some 
variation. Average days of detention were reported from San 
Lazaro as follows: 
TABLE III,—Average time of detention of cholera carriers at San Lazaro. 
is Month. Males. |Females. 
Days. | Days. 


! 
DAML G re ae ee i oe i eg RS Sc 7 | 8 | 
' 
ATU SS Ces oe oe eee eee ee eee a 5 oe eee ek ee ener eet 8 6 
However, very likely some of these cases which were reported 
as cleared up were intermittent carriers and again became tem- 
porary disseminators of disease germs, and thus the average 
period of infectivity as given above is probably too short. 
Experience would seem to indicate that in an outbreak of 
