Immunization by vaccination was first introduced by? February 1, 2021 / By Preparation Point / Biology Mcqs Share on WhatsApp Share on Facebook Share on Twitter Share on LinkedInA. Fleming in 1945 B. Florey & Chain in 1975 C. Flore & Chain in 1795 D. Edward Jenner in 1795 Share this:TwitterFacebookMoreTelegramWhatsAppLike this:Like Loading... Related Share on WhatsApp Share on Facebook Share on Twitter Share on LinkedIn