BEIJING • Since late last year, dozens of people in the Chinese city of Wuhan have been infected with a viral pneumonia whose cause is still unknown. A preliminary investigation has identified the respiratory disease as a new type of coronavirus, Chinese state media reported on Thursday, citing scientists handling the investigation.
Experts in China had found the novel coronavirus in 15 of the 59 cases detected as of Wednesday evening, CCTV said. Seven patients were in critical condition, while the rest were stable. Eight were discharged on Wednesday night after they did not exhibit any more symptoms for several days.
Q What are coronaviruses?
A Coronaviruses are a large family of viruses first identified in humans in the mid-1960s. Some transmit easily from person to person, while others do not.
Some coronaviruses are a cause of the common cold, while others found in bats, camels and other animals have evolved into more serious illnesses such as severe acute respiratory syndrome (Sars) and Middle East respiratory syndrome (Mers).
The family derives its name from the Latin word "corona", meaning halo or crown, which the viruses resemble when viewed under an electron microscope.
Q What are the symptoms?
A Common symptoms include runny nose, headache, cough and fever.
Shortness of breath, chills and body aches are associated with more dangerous kinds of coronavirus, according to the US Centres for Disease Control and Prevention.
Q How are coronaviruses spread?
A Many coronaviruses can spread through coughing or sneezing, or by touching an infected person. Chinese officials said the present illness in Wuhan, in central Hubei province, does not transmit readily between people.
Dr Jeremy Farrar, a specialist in infectious disease epidemics and director of British-based global health charity The Wellcome Trust, said that while "a cluster of patients with an unusual respiratory infection is, and should always be, a worry... if the infection is not passing person to person, the level of concern is somewhat reduced".
The Wuhan Municipal Health Commission said some of the patients ran businesses in a seafood market, meaning it is possible that they were infected by animals there.
Operations at the market have been suspended as investigations are under way.
Q How is the Wuhan virus different from Sars and Mers?
A Chinese state media, citing preliminary investigation results, said the Wuhan virus is different from the coronaviruses that were identified in the past. Laboratory tests have ruled out Sars and Mers, as well as influenza, bird flu, adenovirus and other common lung-infecting germs as being behind the current outbreak.
Sars emerged as a novel coronavirus in 2002, first infecting people in southern China, then spreading to more than two dozen countries. More than 8,000 people were infected and more than 700 died. No new Sars cases have been reported since 2004.
Another form of coronavirus causes Mers, an illness that began in Jordan and Saudi Arabia in 2012 before spreading to about two dozen countries. It has resulted in more than 800 deaths, with the majority from Saudi Arabia.
Q When will the Wuhan virus be identified?
A Dr Xu Jianguo, leader of the group that made the preliminary assessment, told the Xinhua state news agency that they will conduct more research over the next several weeks to confirm that it is indeed a new coronavirus.
The World Health Organisation said more comprehensive information is needed to positively identify the pathogen.
Q What are the types of influenza viruses?
A There are three main types of influenza viruses: types A, B and C.
Influenza A and B viruses circulate and cause seasonal epidemics of the disease. Only type A viruses are known to have caused pandemics.
The Influenza C virus is detected less frequently and usually causes mild infections.
ASSOCIATED PRESS, REUTERS, BLOOMBERG, WORLD HEALTH ORGANISATION