US health officials said on Wednesday they had detected a possible case of “community spread” of Covid-19 – the disease caused by the new coronavirus – with a patient testing positive, despite having no travel history to places with outbreaks or of being exposed to someone already infected. The US Centres for Disease Control and Prevention (CDC) statement was released soon after President Donald Trump said in a White House press briefing that he had appointed Vice-President Mike Pence to lead the containment effort against the spread of the illness that emerged in China’s Hubei province. Community transmission – in which multiple cases are detected without any clear source of infection – could significantly weaken the effectiveness of containment measures such as travel restrictions. Trump appoints Vice-President Pence to lead anti-coronavirus efforts “At this time, the patient’s exposure is unknown. It’s possible this could be an instance of community spread of Covid-19, which would be the first time this has happened in the United States,” the CDC statement said. “It’s also possible, however, that the patient may have been exposed to a returned traveller who was infected,” it said. The patient tested positive for the illness after being screened by “astute clinicians” in the public health system in California, the CDC said. Apart from China – where the bulk of the 81,000 plus infections have occurred – countries such as Italy, South Korea, Iran and Singapore are currently experiencing community transmission of the virus to different degrees. The new case brings the total number of coronavirus infections in the US to 60. This includes 45 people who were either brought back from the central Chinese city of Wuhan – the epicentre of the outbreak – or from the Diamond Princess cruise ship in Japan, where hundreds of people were sickened. Purchase the China AI Report 2020 brought to you by SCMP Research and enjoy a 20% discount (original price US$400). This 60-page all new intelligence report gives you first-hand insights and analysis into the latest industry developments and intelligence about China AI. Get exclusive access to our webinars for continuous learning, and interact with China AI executives in live Q&A. Offer valid until 31 March 2020.