xX, B, 1 Munson: Cholera Carriers 4 
itive for cholera. Convict 8617 developed true cholera on Sep- 
tember 27, after being a carrier for seventeen days; convict 
12765 developed true cholera on September 27, after being a 
carrier for sixteen days; and convict 30351 developed cholera 
on September 29, after being a carrier for eighteen days, and 
the disease was of a type sufficiently severe to cause death in 
eight hours. 
Several instances have occurred where persons who had given 
specimens became suspicious of possible findings and absented 
themselves from their usual abodes, so that when later deter- 
mined by the Bureau of Science to be positive they could not 
be found and segregated—only to be taken up later as true 
cholera cases in some other portions of the city. And many 
cases have occurred in which the disease has developed within 
the usual period of incubation, such as convict 8486, who was 
found to be a carrier on September 16 and seveloiyes! active 
symptoms of the disease on September 20. 
What may be the cause of development of the symptoms of 
cholera in carriers can only be surmised with our present knowl- 
edge of the disease. But it is worthy of note that in the Bilibid 
cases at least no causes which might operate to produce a general 
lowering of vital resistance were apparent. They were isolated, 
at rest, well fed, and under every hygienic advantage. 
A number of cases of intermittent carriers have been found, 
and it would probably be shown that these are not rare if re- 
examination of all carriers for a considerable period could be 
carried out. Thus, Mamerto Juanico was found to be a carrier 
on September 16, but was released from quarantine on October 
4 after four negative findings, approximately at two-day in- 
tervals. But on October 26 this case was again found positive 
and so continues at the present time. Here is a case which 
has been an intermittent source of danger for over seven weeks. 
If it can be a carrier for seven weeks, why not for fourteen? 
If the germ can be harbored any such length of time, what 
is the limit of its viability in the intestine? Clearly such cases 
tremendously increase the difficulty of cholera control. 
Take the case of Alejo de la Cruz, who was found positive 
on September 27 and 29 and then was negative for 4 findings 
and released from quarantine on October 14; but who was again 
found positive on October 17, developed choleraic symptoms 
on the same date, and was sent to San Lazaro where he re- 
mained until October 27. Was this last manifestation a sud- 
denly increased virulence of a previously existing but scanty 
infection, or was it a sudden lowering of vital resistance, or 
