This basically comes down to how you define literacy.

Nationally, 21% of Americans have level 1 or below literacy on the PIAAC literacy scale. That's probably where the 85 people came from.

12% are at level 1, meaning they can only read at a basic level. 4% are functionally illiterate, and 4% had some kind of cognitive or physical handicap or language barrier that kept them from being surveyed.

About 34% of illiterate Americans were born outside the US, so they're possibly literature in another language.