33 people have tested positive for the novel coronavirus in California, Governor Gavin Newsom said in a press conference on Thursday. Five of those individuals have since left the state, he said, while 28 others remain in California.
The state is currently monitoring 8,400 people, who have arrived on domestic commercials flights from places of concern, particularly Asia, after 2 February, for possible coronavirus.
California has only an "inadequate" number of some 200 test kits now, Newman said, but has been in "constant contact with federal agencies" to get a significant number of new test kits in the near time.
The first possible transmission was in a resident of Sacramento County, health authorities said earlier.
As of Wednesday, the number of confirmed coronavirus cases in the US stood at 59, the Centers for Disease Control and Prevention (CDC) said.
US President Donald Trump said the outbreak could worsen in the United States, but such a situation was not inevitable. 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.
The coronavirus cases in the United States have so far mostly been travel-related and connected to those who were on board the Diamond Princess cruise ship. There are also cases from those repatriated from Wuhan, the epicentre of the outbreak, as well as those who contracted the deadly virus by person-to-person contact.