With the WHO’s help, Chinese scientists identified the cause — a previously unknown coronavirus — and the source, a fish market in Wuhan, within a few days. The response includes issuing travel advice and disease-management recommendations, as well as provision of supplies for diagnosis and treatment, and guidelines for monitoring and managing the disease.

Whether it will be enough to stop the disease spreading far and killing many people is, of course, impossible to say. That depends on a variety of things; how contagious the disease is (it has just been spotted passing from person to person, as opposed to from animal to human, as it started) and how deadly, for a start.

The area in which it has arisen is also key. The 2013 Ebola outbreak was so deadly partly because poor transport links meant that it was hard to get support to many of the areas it affected. Cultural factors, such as a tendency in west Africa to touch the skin of the dead at funerals, aided its spread.

As for how contagious and deadly the disease is, it’s far too early to say. Jeremy Farrar, the head of the Wellcome Trust, has said that the range of symptoms caused by the coronavirus means that it’s very hard to get a sense of how many people are affected. That could mean that it’s quietly spreading much further than realised, with most people having very mild symptoms.

But it’s worth noting that the disease itself is probably less deadly than others such as SARS and certainly than Ebola. The usual metric for that is “case fatality rate”, i.e. how many cases of infection lead to one death. In SARS it was about 14 deaths per 100 cases. The related Middle East respiratory syndrome (MERS) was more like 34. Ebola was 50.

As of yesterday there had been 278 confirmed cases of the novel coronavirus, and six deaths; a case fatality rate of less than three per 100. Many more people are in intensive care and that number could easily rise, but it looks much less deadly than those other epidemics. If Farrar is right and even more people are infected, then that means the fatality rate is even lower, although of course more infections may still mean more people actually die.

The heartening thing though is that the world has responded much better than it has in the past. The WHO is far from perfect — at the same time as doing this good work, it has been issuing frankly irresponsible advice about e-cigarettes being as dangerous as smoking — but it does seem to have learnt from its past mistakes, and is a useful first line of defence against a real global pandemic.

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Tom Chivers is a science writer. His second book, How to Read Numbers, is out now.

TomChivers

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