Has there been a rise in the rate of communicable diseases, and if so what is attributed to the rise in disease?Discuss

Has there been a rise in the rate of communicable diseases, and if so what is attributed to the rise in disease?
Harm reduction methods are one method that is employed to address public health issues such as communicable diseases.  What harm reduction programs are available to address the rise in communicable diseases among addicts?
Research the success of harm reduction programs, such as needle exchange programs, and briefly discuss your findings.