Disease can be defined as any sickness or illness that shows difference or intrusion of any part of the body’s function or structure; a manifested set of signs and symptoms; whose prognosis, pathology and etiology may be known or unknown. Diseases can be infectious (communicable) or non-infectious (Non-communicable).

Globalization has led to an increase in the connectivity of countries, openness to new ideas and an increase in the financial capital of people which has resulted in both beneficial and harmful effects on their health. The effects of globalization or re-globalization have been a debate across the globe. The focus has been the control of infectious diseases, national threats security, provision of urgent medicines, changes in international trade and finance agreements to help improvise accessible treatments. The last few decades have witnessed great advancements in the control of life threatening infectious diseases, primarily due to the focus on sanity and food safety issues, development of new vaccines and antibiotics and improved nutrition. This has resulted the people to believe that medical science would succeed in over riding these obstacles to further improve the health of populations especially in the underprivileged societies. With the help of vaccination campaigns, diseases such as smallpox have been eradicated, poliomyelitis is close to being eradicated, and the incidence of many infectious diseases such as diphtheria, tetanus and measles has greatly reduced. Although communicable diseases such as HIV and many forms of influenza have constantly surprised researchers and have renewed challenges before the public health community, immense hard work is being put into development of treatments for such diseases. The emergence of new antibiotic-resistant strains of common microorganisms due to the over use of antibiotics and scarce vaccine production are challenges before the community and humanity at large. This stresses on the need for novel effective vaccines and antibiotics and to have strengthened positive environmental measures of control.

Immense knowledge on origins of cancer such as that of the stomach, liver, cervix has initiated the development of preventive measures which have also evolved into cures that are now found for other chronic diseases. Tragically, hundreds and thousands of deaths are occurring in the developing countries due to long delays in adopting cost effective medicines and vaccines, while tuberculosis, malaria and other diseases still remain global health issues. Acquisition of advanced knowledge, risk communication, research and application of resources are a fair few challenges to the public health in the decades to come.