Section 2(m) in The M.P. Chechak Tika Adhiniyam, 1968
(m)"unprotected child" or "unprotected adult person" means a child or an adult person, as the case may be-(i)who has not had smallpox, either naturally or by inoculation; or(ii)who has not been successfully vaccinated; or(iii)who has not been certified or deemed to be certified under this Act or any other law for the time being in force to be insusceptible to vaccination;
