CONTROL OF INFECTIOUS DISEASES 773 



Directions for use: 



Prepare the room to be disinfected by sealing all cracks, windows, ventilators, 

 etc , and all the doors but the one for exit, with wet newspaper strips; open all 

 blankets, drawers, etc.; separate and open up all books, clothing, etc., in the room. 

 Have wet strips of paper in readiness to seal the last door when the disinfection 

 has been started and the operator has left the room. The windows should be left 

 unlatched so that they may be opened from the outside after the disinfection is 

 completed. 



Use a metal pail with lapped (not soldered) seams, or an earthenware receptacle, 

 holding not less than fourteen (14) quarts, in which to mix the above ingredients. 

 Place the receptacle on bricks standing in a pan of water, but the receptacle should 

 not touch the water. 



Place the n ounces of potassium permanganate in the receptacle, distributing it 

 evenly over the bottom. 



Mix the formaldehyde (n ounces) and the water (9 ounces), and pour this 

 mixture over the potassium permanganate in the receptacle. 



This done, the operator should leave the room as quickly as possible, sealing the 

 door behind him with the wet strips of paper prepared in advance for this purpose. 



The directions above apply to the disinfection of a room' containing 1,000 cubic 

 feet or less. If a room contains more than 1,000 cubic feet of space, use one of the 

 above disinfecting outfits for each 1,000 cubic feet or fraction thereof. Do not 

 attempt to use a double charge in a container of even double capacity. 



In disinfecting a whole house, begin with the most distant room and having 

 mixed the potassium permanganate, formaldehyde, and water in the proper re- 

 ceptacle, close the door of the room and seal it at once as directed above. Proceed 

 in this way in the disinfection of all the rooms. Leave the seals unbroken on the 

 window and doors for six hours, after which the rooms should be opened up and 

 thoroughly aired. The temperature of the room at the time of disinfection should 

 not be below 7oF. 



No paper, cotton, cloth, wood, or other combustible material should be in or near 

 the disinfecting outfit for fear of fire, and no flame should be permitted in the room 

 near the disinfecting outfit. 



CARRIAGE OF INFECTION BY BIOLOGICAL AGENTS 



The transmission of yellow fever and malaria by mosquitoes, in the 

 course of which the parasite causing the disease must undergo a whole 

 series of developmental changes before the mosquito can become infective, 

 is now well understood. But the mechanical carriage of infec- 

 tious material by flies from privy vaults or bed pans or even mucous 

 membranes or open wounds to food and drink or to other mucous 

 membranes or wounds has not been very long established. 



That typhoid fever and dysentery have many times occurred in 

 epidemic form chiefly by the carriage of the infective agents by flies the 



