With the onset of the epidemiological transition and as the prevalence of infectious diseases decreased through the 20th century, public health began to put more focus on chronic diseases such as cancer and heart disease. Previous efforts in many developed countries had already led to dramatic reductions in the infant mortality rate using preventive methods. In Britain, the infant mortality rate fell from over 15% in 1870 to 7% by 1930.
A major public health concern in developing countries is poor maternal and child health, exacerbated by malnutrition and poverty. The WHO reports that a lack of exclusive breastfeeding during the first six months of life contributes to over a million avoidable child deaths each year.
Public health surveillance has led to the identification and prioritization of many public health issues facing the world today, including HIV/AIDS, diabetes, waterborne diseases, zoonotic diseases, and antibiotic resistance leading to the reemergence of infectious diseases such as tuberculosis and antibiotic resistance, also known as drug resistance.
Further, the WHO reports that at least 220 million people worldwide have diabetes. Its incidence is increasing rapidly, and it is projected that the number of diabetes deaths will double by 2030. In a June 2010 editorial in the medical journal The Lancet, the authors opined that “The fact that type 2 diabetes, a largely preventable disorder, has reached epidemic proportion is a public health humiliation.” The risk of type 2 diabetes is closely linked with the growing problem of obesity. The WHO’s latest estimates as of June 2016 highlighted that globally approximately 1.9 billion adults were overweight in 2014, and 41 million children under the age of five were overweight in 2014. Once considered a problem in high-income countries, it is now on the rise in low-income countries, especially in urban settings.