Q Is it possible that the disease is airborne and not a virus? If so, how much more dangerous would it be to Hong Kong?
A The major mode of transmission is through droplets spread when an infected person coughs or sneezes and droplets are spread to a nearby contact. But Dr Julie Gerberding, the director of the Centres for Disease Control and Prevention (CDC) in Florida, said in a media briefing on Saturday: 'We are concerned about the possibility of airborne transmission across border areas and also the possibility that objects that become contaminated in the environment could serve as modes of spread.' Hong Kong's Director of Health, Margaret Chan Fung Fu-chun, also said on Saturday that the government was very concerned about infection on estates and would not rule out that the Sars virus might be airborne. Sars is caused by a virus, with the leading hypothesis being that it is caused by a new coronavirus, the type which causes common colds. International laboratories are still exploring the possibility of it being another type or types of virus, according to the World Health Organisation and the CDC.
Q Is the diagnostic test for Sars available to everyone or just people suspected to have the disease?
A The diagnostic test is used to confirm a doctor's initial diagnosis of Sars and is not used as a mass screening test. At 60 per cent sensitivity, it can produce a lot of false negatives, according to Dr Lo Wing-lok, legislator for the medical sector and a specialist in infectious diseases. To diagnose Sars, doctors still use their clinical judgment on the symptoms and chest X-rays as the most useful screening tests. The diagnostic test, developed by a University of Hong Kong medical team, is used for patients already diagnosed with Sars symptoms. Test results can be obtained in about eight hours.
Q My friend has left Hong Kong with her children until the scare over the virus blows over. Should I do the same, and if I do, is it safe to travel by aeroplane?