Our gut is permanently full of large numbers of bacteria but serious infections rarely occur due to its extraordinary immune system. Public health has reduced but not eliminated transmission of these potentially dangerous infections.
The most common cancer in men in the UK is prostate cancer, around a quarter of all male cancer diagnoses. Testicular cancer, the other male-specific cancer, is rare, but occurs early in life. Neither are preventable.
Lung cancer is the second most common cancer in both men and women, but kills the most people through a combination of being common and currently having much less effective treatment. Both treatment and prevention are currently improving, slowly.
The relative role of the State and the individual is a recurring theme of political theory. It is also a practical question in public health – what are the respective responsibilities of government, individuals and healthcare professionals to protect health?
Ill health has always been concentrated in particular places; tackling these pockets of ill health is an essential role for public health. These may be driven by environmental factors, demography, deprivation and healthcare provision.