Synonyms for Infectious (same or very similar meaning)
WordNet sense 1 (caused by infection or capable of causing infection):
infective
WordNet sense 2 (containing or resulting from disease-causing organisms):
infected, septic
WordNet sense 3 (easily diffused or spread as from one person to another):
contagious
WordNet sense 4 ((of disease) capable of being transmitted by infection):
catching
From the ODE community, based on WordNet
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