"I did notice there was a whole bunch of people using hand sanitizers and stuff," parishioner Jody Snow said.
It's a response to a letter from Michael Burbidge, bishop of the Catholic diocese of Raleigh, addressing concerns raised by the swine flu virus.
The bishop asks all ministers to wash their hands before and after mass.
He also wants people to use discretion during Holy Communion, especially if they're feeling ill.
"He did suggest that you not pass the cup, the same with the sharing of our sign of peace with one another," Snow said.
In those cases, the bishop advises taking "a deep bow, or a nod of the head" instead of a handshake.
Those attending Mass on Sunday said they found the bishop's letter outlining those 'common sense precautions' inside the bulletin, at the Sacred Heart Cathedral and at other churches across the diocese.
The bishop is asking for compliance among the faithful until the risk of flu subsides.