DISINFECTANTS. ANTISEPTICS 175 



anthrax spores, tubercle bacilli, tetanus spores, black leg spores, 

 and the contagion of lung plague and rabies are destroyed with 

 difficulty. For the purposes of practical disinfection, the more 

 important infectious diseases can therefore be classified in two 

 groups, the one including those for which a mild disinfectant is 

 sufficient and the other those which require a strong disinfectant. 

 The following groups are arranged on this basis: 



A. Requiring strong disinfectants : 



Anthrax spores. 

 Tetanus spores. 

 Tubercle bacilli. 

 Black leg spores 

 Lung plague virus. 

 Rabies virus. 



B. Requiring mild disinfectants: 



Anthrax bacilli. 



Swine erysipelas baciUi. 



Glanders bacilli. 



Bacteria of hemorrhagic septicaemia. 



Foot-and-mouth disease virus. 



Pox and rinderpest virus. 

 Staphylococci and streptococci occupy a position between 

 these two classes. They are much easier to destroy than spores 

 and spore-containing bacilli, but are considerably more resistant 

 to disinfectants than the spore-free organisms. For these reasons, 

 it is necessary to use the more powerful disinfectants (corrosive 

 sublimate, creolin, tincture of iodine) in the antiseptic treatment 

 of wounds in order to destroy the pus cocci (staphylococcus 

 pyogenes, streptococcus pyogenes). 



Method of Action of the Disinfectants. — It has already been 

 stated that infectious material may be rendered ineffective either 

 through destruction of its vitality or through inhibition of its 

 development. In either case the method of action may be very 

 different. In general, disinfection is the result of the following 

 processes: 



1. By coagulating the bacterial albumins (mycoproteins) the 



