In a small U.S. town of 10,000 people, 250 residents will die each year and 100 of those will be children under 5 years old. Few people in the town will live beyond 50 years old. Of all the children born there, 10% will die before their first birthday and 24% before their 5th birthday.

This town is not the setting of a dystopian novel or film. Instead, it describes the average mortality rate and life expectancy in the United States in 1900. In that year, five infectious diseases—pneumonia, influenza, tuberculosis, gastrointestinal infections, and diphtheria—caused more than one-third of all deaths, and vaccines existed for only smallpox and rabies.

In its 12,000 years of circling the globe, smallpox alone is estimated to have killed hundreds of millions, including as many as half a billion people worldwide in the 20th century alone. However, the smallpox vaccine was so effective the World Health Organization (WHO) launched its Smallpox Eradication Program in 1959. By 1980, the WHO declared smallpox eradicated worldwide—the only infectious human disease successfully extinguished.

Despite the effectiveness of local and global smallpox inoculation campaigns, for decades, the vaccine provoked fear, ignorance, apathy, and resistance—find out why and read the full article at brighammag.org.