Microbiology Salmonella typhi is the causative agent of typhoid fever. The infective dose of S.typhi – A One bacillus B 108 - 1010 bacilli C 102 - 105 bacilli D 1 - 10 bacilli π‘ Explanation Salmonella typhi is the causative agent of typhoid fever. The infective dose of S.typhi - β Correct Answer: C. 102 - 105 bacilli