Twelve of the cases are travel-related, two were contracted by person-to-person spread, 42 were on board the Diamond Princess cruise ship and three were repatriated from the city of Wuhan in China where the outbreak began, the CDC said.
The US government has begun preparing for a potential novel coronavirus epidemic within the United States after reported outbreaks in Iran, South Korea and Italy escalated this week.
Washington said it fears that an epidemic could hurt global growth and weaken financial markets worldwide.
The outbreak of pneumonia caused by a new strain of coronavirus was first registered in the Chinese city of Wuhan, in Hubei province, in December, and has since spread to more than 30 countries worldwide.
A global health emergency was declared by the World Health Organisation over the novel coronavirus outbreak.