A coronavirus particle has spikes on its surface with knobs on the ends, making it look a bit like the sun and its corona. Hence the family name. Human ones were first seen in the 1960s by the electron microscopist June Almeida, in collaborative common cold research with the virologist David Tyrrell. Growing the viruses was very difficult. Almeida and Tyrell were enthusiasts for organ culture (I am reminded of it daily; I worked with June and have a scar on my forearm where skin was taken in a vain attempt to grow wart viruses). Bits of tissue kept alive in test tubes were infected with sneezings from common cold sufferers. It turned out that a quarter of colds are caused by coronaviruses.
In 2002-3 SARS joined the family. A 10 per cent mortality rate from pneumonia drove diagnostic improvements. No longer is it necessary to have virological green fingers. Nucleic acid sequencing is rapid, accurate and informative. The results of tests done in Rotterdam on lung tissue from a 60-year-old who died from pneumonia in Saudi Arabia in July have been compared with samples from a Qatari with severe pneumonia who had visited Saudi Arabia, fell ill in Doha on 3 September, and been transferred by air ambulance to a private hospital in London on 11 September, where he is in full isolation. There is a 95 per cent similarity in gene sequence. The virus is new. It is not SARS.
The SARS virus probably came from fruit bats that had then infected civet cats. Does the new virus have an animal source? Will it spread? Does it always cause severe infections? Only time will tell. But I am glad not to be a public health official concerned with the forthcoming Hajj.