Pandemic smallpox was responsible for 300–500 million deaths. As recently as the early 1950s, an estimated 50 million cases of smallpox occurred in the world each year. After successful vaccination campaigns throughout the 19th and 20th centuries, the WHO certified the eradication of smallpox in December 1979. To this day, smallpox is the only human infectious disease to have been completely eradicated, and one of two infectious viruses ever to be eradicated. Historically, measles was prevalent throughout the world, as it is highly contagious. According to the U.S. National Immunization Program, 90% of people were infected with measles by age 15.
To Be, To Be, Ten made To Be has been certified gold for shipments of over 100,000 by the Recording Industry Association of Japan. To Be, To Be, Ten made To Be "To Be, to Be, Ten Made to Be" is Tackey & Tsubasa's debut single under the Avex Trax label. This is the first retail single for their 2wenty 2wo album. "To Be, to Be, Ten Made to Be" is the debut single released by singer duo Tackey & Tsubasa. The a-side song "Sotsugyou:Sayonara wa Ashita no Tameni" was used as the insert song for the anime InuYasha on episode 124, only the version of the song