Preliminary tests identified the source of the outbreak as the highly contagious norovirus, which had struck several guests just before they boarded the cruise Nov. 3 in Rome, Carnival officials said.
the source of the outbreak was dengue fever
( z1 be-from :ARG1 ( z2 outbreak ) :ARG2 ( z3 disease :name ( z4 name :op "Dengue" :op "Fever" ) ) )