Death rates in the 20th century

Cause of Deaths

The 20th century saw a transition from infectious diseases such as influenza, to degenerative diseases such as cancer or diabetes as the leading cause of death in the developed world. In 1900, the leading cause of death in the United States was Influenza with 202.2 deaths per 100,000 people followed by tuberculosis with 194.4, which is an easily curable illness today. In the middle of 20th century America, the leading cause of death was heart disease with an impressive 355.5 deaths per 100,000 followed by Cancer at 139.8 deaths per 100,000. Although death rates dropped significantly in the latter part of the 20th century, the leading killers are still constant. The United States saw 129.9 people per 100,000 die from heart disease in 2010 followed by cancer with 185.9 people per 100,000.

Aging Population

A natural population increase transpires when birth rates are higher than death rates. However, post World War II saw an explosion in birth rates faster than would be natural, called the Baby Boom. The Baby Boom occurred when all of the soldiers returned to their homes around the world and started new families. Death rates were significantly lower during the post World War baby boom and thus populations increased substantially. The mass population of people that were all born simultaneously during the Baby Boom, are aging together, meaning the overall population is getting older. The aging population means there will be a dramatic decrease in population size from the increase in death rates over the next decade or so.

Fertility rates and consequently live birth rates declined over the century, while age-adjusted death rates fell more dramatically. Children in 1999 were 10 times less likely to die than children in 1900.

For adults 24–65, death rates have been halved. The death rate for Americans aged 65 to 74 fell from nearly 7% per year to fewer than 2% per year.

The introduction of vaccines for several diseases led to reduced mortality from them. Again developed countries felt the greatest benefit. In the 20th century, vaccines became available for many diseases which caused deaths: diphtheria, pertussis, tuberculosis, tetanus, yellow fever, polio, measles, hepatitis among others.

However, war, genocide and Holocausts led to many millions of deaths throughout the century, and late in the century AIDS had already killed millions, particularly in Africa and south-east Asia. Cancer also killed millions via lifestyle and pollution generated by industrialization.

See also

• Death rate
• List of countries by death rate
• Birth rate