Garrison Keillor notes three happy events on this date in his daily “Writer’s Almanac.”

Jonas Salk released his life-saving polio vaccine in 1954, which almost completely eliminated this scourge. How well I remember the terror all children felt in the early 1950s. We were warned not to go to movies or other public spaces. If we went, we were warned not to put our heads on the headrest.

By this time, there was tremendous pressure to find an effective way to control the disease: 1952 saw the worst outbreak in America’s history, with nearly 60,000 cases reported; more than 3,000 people died and more than 21,000 were left disabled. Salk knew that he needed to begin testing his vaccine on a large scale, and quickly. He set up a makeshift lab in the gymnasium of Arsenal Elementary School in Pittsburgh, and personally administered his vaccine to 137 schoolkids. A month later, he announced that the first trial was a success, and he soon expanded his efforts across the country. By the time the vaccine was announced to be safe and effective in 1955, 1.8 million schoolchildren had received the vaccine.

In 1952, 60,000 people contracted polio in the United States alone; 60 years later, in 2012, polio cases numbered only 223 in the entire world.

And more:

It’s the birthday of scholar and civil rights activist W.E.B. Du Bois (books by this author), born in Great Barrington, Massachusetts (1868). Du Bois was the first African-American to earn a Ph.D. from Harvard University. He decided to write about racism and the African-American experience. He published a landmark book, The Philadelphia Negro: A Social Study (1899). The book popularized Du Bois’s phrase “the talented tenth,” a term describing the likelihood of one in 10 black men becoming leaders of their race. He also wrote The Souls of Black Folk, a collection of essays (1903).

In 1905, Du Bois met with 30 other African-American scholars, artists, and activists in Canada, near Niagara Falls, to discuss the challenges that people of color faced. The men had to meet in Canada because blacks were not allowed rooms at white-run U.S. hotels. It took a few years, but from this first meeting sprang the formation of the NAACP, the National Association for the Advancement of Colored People (1909), which still exists today to fight racism and bridge cultural divides.

It was on this day in 1940 that Woody Guthrie (works by this artist) wrote the lyrics to “This Land Is Your Land” — now one of America’s most famous folk songs.

The melody is to an old Baptist hymn. Guthrie wrote the song in response to the grandiose “God Bless America,” written by Irving Berlin and sung by Kate Smith. Guthrie didn’t think that the anthem represented his own or many other Americans’ experience with America. So he wrote a folk song as a response to Irving Berlin’s “God Bless America,” a song that was often accompanied by an orchestra. At first, Guthrie titled his own song “God Blessed America” — past tense. Later, he changed the title to “This Land Is Your Land,” which is the first line of the song.

Although Guthrie wrote the words to the song in his notebook on this day in 1940, he didn’t perform it until 1944, and it was several years more still before he published it in a book of mimeographed folk songs. The song really took off in the 1960s. Bob Dylan did a famous version, and it became a popular anthem during the Civil Rights movement.