"Occupational disease" means such disease or infection as arises naturally and proximately out of employment under the mandatory or elective adoption provisions of this title.
[ 1961 c 23 s 51.08.140. Prior: 1959 c 308 s 4; 1957 c 70 s 16; prior: 1951 c 236 s 1; 1941 c 235 s 1, part; 1939 c 135 s 1, part; 1937 c 212 s 1, part; Rem. Supp. 1941 s 7679-1, part.]