"Rockin' Pneumonia and the Boogie Woogie Flu" is a song written and originally recorded by Huey 'Piano' Smith in 1957, who scored a minor hit with the song (No. 52 Billboard).

1972 saw the song as an international hit single for Johnny Rivers with instrumental backing from L.A. sessions musicians from the Wrecking Crew. "Rockin' Pneumonia" reached number six on the U.S. Billboard Hot 100 during the winter of 1973. It was only Rivers' fifth highest charting song, but spent much longer on the chart (19 weeks) than any of his two dozen hits to that date. On the U.S. Cash Box Top 100 the song peaked at number five, and in Canada it reached number three.

Rivers' cover of "Rockin' Pneumonia" became his third Gold record. His last Gold record would be five years later with the 1977 hit, "Swayin' to the Music (Slow Dancing)."

...
Wikipedia