Antibody
noun
Confront your body? Sounds like it's something that's against bodies... perhaps, something that's antibody?
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
どうしてボスに逆らって、そのウィルスへの抗体を作り出そうとするのですか？予防接種を受ける！
Why do you defy your boss and try to build up antibodies to the virus? Get a vaccination!