Diseases can be caused in many ways some can spread and some cannot the diseases which spread are known as infectious diseases and the diseases which do not spread are called are non infectious diseases.
The diseases such as B.P, cancer, Heart attack etc they don not spread such diseases are called as non infectious diseases.
They are caused due to unproper food conditions, consumption of alcohol and smoking and over tensed conditions and sudden shocks causes these all diseases.
And the infectious diseases are those which spread such as skin diseases, malaria, common cold, AIDS etc.
These can be through...
Sexual Contact- AIDS
Hope this may help u..