Mo. Rev. Stat. § 210.040: Blood test results — confidential.

As soon as the result of the test is determined, and if the test is positive or doubtfully positive for syphilis or hepatitis B, the physician, or such other obstetrical or gynecological attendant shall fill out a form to be furnished by the department of health and senior services of Missouri, with such finding noted thereon, and send it to the county or municipal department of health of the county or city in which the pregnant woman or the mother is then residing. In no event shall this finding be made public by any person.