GOVERNMENTAL SERVICES 141 



Diseases which were formerly not considered sub- 

 ject to it are today restricted by its use; and it is 

 not unlikely that diseases which are not today 

 recognized as spread by germs may later be 

 stamped out by quarantine. 



106. Methods in Quarantine. Formerly quar- 

 antine consisted simply in preventing the entrance 

 of persons or animals upon infected premises, or 

 their exit therefrom. Fences were erected around 

 yellow fever premises, but the disease spread. 

 Now effective quarantine is maintained by screen- 

 ing in the patient, and killing the mosquitoes. 

 After three days the yellow fever patient is no 

 longer able to transmit the disease to the stego- 

 myia mosquito, and further quarantine is useless. 

 The malarial patient must be kept under guard 

 sometimes for months. Eats, and the fleas which 

 they carry, are the means by which the bubonic 

 plague is spread. Quarantine in these cases there- 

 fore means destruction of the vermin for a certain 

 district, always working from the outside of a 

 circle in whose centre infection has been found.^*^ 



In veterinary practice a quarantine may mean 

 only the restriction of certain kinds of animals, 

 or the restriction of the passage of all members 

 of the animal kingdom. For the Texas cattle 

 fever quarantine includes killing the ticks, either 

 by dipping the infected animals, or by destroy- 

 ing the animals and disinfecting the premises. 

 Infected animals may be useful for food purposes, 

 so that burning the carcasses is not necessary, as 

 it is for anthrax. Anthrax has been known to be 



26PUBUC HeAI/TH, §§402, 

 403. 



