The term "germ free" does not appear to be part of the official title or a primary theme of the 1973 film. It is possible this is a misremembered detail or a reference to (the "Bubble Boy"), whose famous "germ-free" life in a sterile plastic bubble also began in 1971 and was a major news topic throughout the 1970s. 14 and Under (1973)
This phrasing often appears in government or institutional reports (like early awakening report 14 and under 1973 germ free