Some Occupational Hazards (Continued) 



SKIN IRRITANTS 



PHYSICAL STRAINS 



EXPLOSIONS AND OTHER ACCIDENTS 



In Brief 



With every improvement in economic conditions, there is a consistent 

 lowering of sickness and mortality rates. Among underprivileged groups both 

 sickness rates and death rates are relatively high. 



To make use of new knowledge and to fit into changing conditions, in- 

 dividuals and members of families need constantly to re-educate themselves 

 and to change their practices. 



The spread of communicable diseases can be prevented by attacking the 

 parasites at the point where they leave the host, in the course of transit to a 

 second host, or at points of entry into the body. 



By exterminating flies and mosquitoes, it has been possible to reduce radi- 

 cally or even to eliminate typhoid fever, malaria, yellow fever, and other diseases. 



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