3 66 THE POPULAR SCIENCE MONTHLY 



Disinfecting Wharf., Tampa Quarantine Station, Florida. 



tory, have recently proved the identity of typhus and " Brill's disease/' 

 a disease fairly often seen in large cities. They have also shown the role 

 of the body louse in transmitting typhus. The isolation period for sus- 

 pects is fourteen days. 



No more terrible epidemic has ever threatened this country than 

 bubonic plague and against the entry of no disease are more rigid pre- 

 cautions taken. It exists constantly in oriental countries, especially in 

 China and India, and the great danger of introduction here always con- 

 fronts us. There are several forms of plague, of which the pneumonic 

 type is the most deadly. This was the prevailing type in the recent 

 epidemic in northern China. The bacillus of plague lives and multi- 

 plies in the blood of the victim. It also causes an epizootic in rats and 

 certain other rodents, and from these, as well as from human cases, the 

 bacilli are carried to human victims through the agency of fleas and 

 bedbugs. In addition pneumonic plague is highly infectious directly, 

 spreading from man to man by aerial convection. It is very easily seen 

 how important is the eradication of plague epizootic among rats, ground 

 squirrels and other rodents as is being done now in California. An 

 epizootic is a powder magazine waiting only for the match of proper 

 local conditions to explode in all directions in an epidemic of the 

 greatest virulence. 



Quarantine measures against plague first of all aim to prevent in- 

 fected cargo, baggage or ballast from being shipped. To this end rat 

 guards are used, all suspicious articles going on the vessel are thor- 

 oughly disinfected and special efforts are made to destroy all rats on 

 board. Cases of plague reaching a domestic quarantine station are 

 isolated and the surroundings and belongings thoroughly disinfected. 



