Chinese health authorities say that they have discovered four more cases of pneumonia following an outbreak of what is believed to be a new corona virus strain in the central city of Wuhan, raising concerns that the disease could spread further.
The four individuals were diagnosed with pneumonia on Thursday and are in a stable condition, the Wuhan Municipal Health Commission said in a statement published shortly after midnight, a day after it confirmed the death of a second patient.
Nearly 50 people are known to have been infected and so far involve only individuals who have travelled to or live in Wuhan, but the World Health Organization (WHO) has warned that a wider outbreak is possible.
Many of China's 1.4 billion people will be travelling abroad during the Lunar New Year holidays next week, raising concerns about the disease spreading to other countries.
A report published by the London Imperial College's MRC Centre for Global Infectious Disease Analysis asserted there are likely "substantially more cases" of the new corona virus than the 45 currently announced by Wuhan authorities.
A summary of the report on the centre's website says its baseline scenario estimates that there would be 1,723 cases showing onset of related symptoms by 12 January. The full report was not available, however.
The Wuhan commission referred queries on the report to China's National Health Commission and the Hubei provincial government.
The National Health Commission and the Hubei government did not immediately respond to requests for comment.
Thailand reported two cases of the corona virus from Chinese travellers from Wuhan this week, while Japan confirmed one case involving a Japanese national who travelled to Wuhan.
Memories remain fresh in Asia of a 2002/03 outbreak of Severe Acute Respiratory Syndrome (SARS), which emerged in China and killed nearly 800 people worldwide.
Corona viruses are a large family of viruses that can cause infections ranging from the common cold to SARS.
Health officials say the new virus discovered in Wuhan does not appear to be as lethal as SARS, but admit they still know little about it, including its origins or how easily it can be transmitted from person to person.
A seafood market in Wuhan is believed to be the epicentre, but authorities say some patients they have identified deny having any exposure to this market.
US authorities have said they would start screening at three airports to detect travellers arriving via direct or connecting flights from Wuhan who may have symptoms of the new virus.
In Asia, authorities in Singapore, South Korea, Taiwan and Thailand have stepped up monitoring of passengers from Wuhan at airports.
Indonesia, Malaysia and the Philippines say they have strengthened screening at all points of entry in response to the outbreak, as well.
Japan screens all incoming travellers for high temperatures and started displaying notices at airports around the country asking passengers to come forward if they have travelled to Wuhan and have become sick.
Australia, which saw about 1.4 million short-term arrivals from China last year, is not planning any special screenings for now.
The WHO has said it advises against any travel or trade restrictions on China.