Ten years ago the world was gripped by the threat of SARS (severe acute respiratory syndrome), which was caused by a coronavirus. The outbreak infected more than 8,000 people and around 800 died.
Over the past six months a new coronavirus has come to light, beginning with cases in the Middle East, but spreading to Europe. There have been over 30 cases of infection so far, 24 in Saudi Arabia, where over half of those infected have died. Cases in Europe have been linked to travellers returning from the Arabian Peninsula.
The agent has been called novel coronavirus 2012 (officially London1 novel CoV 2012). The virus is in the same family as the SARS virus, but has some different biological features.
How does it spread?
The new coronavirus is most probably transmitted by coughs and sneezes (droplet infection), but there is also a possibility of infection through skin contact, which was suspected in the SARS outbreak. The novel coronavirus causes severe respiratory illness and some patients have died from renal failure.
Coronavirus infections are common in animals but are not commonly passed on to humans. This type is thought have arisen from bats and has been shown to be transmitted from human to human. However, the strain does not seem to be highly infective, since each of the case clusters in the Middle East and in Europe has been small.
The World Health Organization has not recommended restrictions on travel but the United States Centers for Disease Control advises people travelling in the Arabian Peninsula to be vigilant about personal hygiene and avoid contact with people who have a respiratory illness. It recommends that travellers in the Middle East who develop a cough or shortness of breath should seek medical assistance.
There is no specific treatment for coronavirus infection. Infected individuals should be isolated and a barrier nursing system should set up, with personal protective suits and masks to protect health care personnel. Management is aimed at relieving respiratory distress and symptoms of renal failure.
Director of the US National Institute of Allergy and Infectious Diseases, Anthony Fauci, has reported that the virus responds to a combination of two standard antiviral agents (ribavirin and interferon alpha 2b) in laboratory settings, but no animal or human trials have been conducted. Ribavirin and interferon are already widely used to treat hepatitis C.
Should we be concerned?
There is no specific risk to Australia at this stage, as there are small clusters in the Middle East and Europe, with limited person-to-person transmission.
But if the number of novel coronavirus cases in the Middle East continues to rise, it may be necessary to set up a special system to track pilgrims returning from the Hajj. The Hajj is in mid-October this year, and about two million Muslims from all parts of the world visit Saudi Arabia for the great pilgrimage. Thailand has already recommended that Muslims returning from the Hajj routinely receive a medical check on return.
While the threat of the novel coronavirus is of concern, our main attention should still be focused on the potential for rapid spread of H7N9, a new bird flu virus which has infected around almost 100 individuals in China in recent weeks and has killed about 20% of patients so far.
The new bird flu virus has spread among chickens in China and is transmitted from birds to humans, but human-to-human transmission has not so far been recorded.