"People should be considering the possibility of substantial human-to-human transmission more seriously than they have so far", he continued, saying it was "unlikely" that animal exposure was the sole source of infection.
The clinical signs and symptoms of coronavirus infection are mainly fever with a few patients having difficulty in breathing, the Indian travel warning said.
Two people are known to have died from the respiratory illness which appeared in Wuhan city in December. A lot of them appear to have left for home for the Chinese New Year holidays. Meanwhile, the World Health Organization (WHO) said yesterday officials see evidence of limited human-to-human transmission, adding that it's closely watching for signs of sustained spread. There have also been reports of people infected with coronavirus outside of China who had recently traveled to Wuhan.
This comes as passengers from Wuhan will be subject to health screenings at New York's JFK airport as well as airports in San Francisco and Los Angeles starting on Saturday.
Wuhan officials have been providing updates on new cases nearly daily since 11 January, and 17 is the highest number reported since then.
These patients showed symptoms such as fever or cough before January 13, according to Wuhan Municipal Health Commission.
The total number of patients infected by the disease in China, all of them in central Chinese city of Wuhan, has now climbed to 62.
Authorities said on Sunday that some of the cases had "no history of contact" with the seafood market believed to be the centre of the outbreak.
CDC officials say people shouldn't freak out and that more common illnesses such as the flu are much bigger threats to Americans than this new virus from China.
India on Friday issued an advisory to its nationals visiting China following a second death due to the outbreak of the new strain of pneumonia in the Chinese city of Wuhan where over 500 Indian medical students are studying.
One estimate Friday by the MRC Centre for Global Infectious Disease Analysis at Imperial College London suggested that there could be as many as 1,700 cases.
The researchers estimated there have been 1,700 cases of the coronavirus, and up to 4,000 cases.
Scott Pauley, a CDC spokesman, told VOA the CDC anticipates a higher number of Chinese travelers to the United States for the new year and has factored this into its planning.
"It still requires close monitoring for any possible mutations", the commission said.
The outbreak of this virus was trending on Weibo, a microblogging platform in China.