In the case of any county taking over the responsibilities of an independent local health special district created pursuant to Chapter 6 (commencing with Section 880) of Part 2 of Division 1 of the Health and Safety Code, as enacted by Chapter 60 of the Statutes of 1939, for purposes of computations pursuant to this chapter, the amount of state assistance payments with respect to that county shall be increased by five hundred four thousand nine hundred fifty-seven dollars ($504,957).