Highly Infectious, Not Very Lethal

Still focused on the Diamond Princess, because it’s a microcosm of the new coronavirus outbreak, isolated from all the others. We should get a fairly good idea of just how infectious it is, and just how lethal. The passengers and crew of this ship have become the guinea pigs in a medical experiment. And there seem to be all different races present.

A headline I read today –

The news from the cruise ship moored in quarantine in Japan is awful – coronavirus cases aboard are soaring

– probably arose from the fact that there were first 10 cases, and then 20 cases, and now 60 cases. But this may simply be because the results from some 270 or so tests have been only slowly coming out over a period of several days. It looks like it took 3 days for 270 tests to be completed, so they could only do about 90 tests per day.

So what it probably means is that when the tests were carried out, nearly a quarter of the passengers sampled were already infected.

And that shouldn’t be too surprising. As far as I can see, life aboard these sorts of cruises is pretty much one long party. People go on them primarily in order to socialize. So they’ll all have been mingling with each other closely during the 15-day voyage. Timeline:

The checks began after an 80-year-old Hong Kong man who had been on the ship last month fell ill with the virus.

He boarded the cruise ship in Yokohama on 20 January and disembarked in Hong Kong on 25 January.

Where had he been before he boarded in Yokohama? If he’d just arrived from Wuhan, he was probably a carrier. If not, then he likely picked it up on board from some other carrier.

The captain announced the discovery of coronavirus on 3 Feb. Two days later, 5 Feb, passengers were confined to their cabins. Same day, 10 cases were found on the ship. Next day, 6 Feb, another 10 were found. Today another 40. But these numbers are probably just the results of 270 tests carried out (on 4 Feb?) slowly trickling out.

If they get round to testing everybody, it rather looks like they’ll find that 60/270 or 22% of everyone on board  is carrying the virus.  And that will be something approaching 1000 cases.

However, 19 days after the 80-year-old Hong Kong man boarded the ship, nobody has died. And if the virus had been on the ship for 10 days before he arrived, then in an entire month nobody will have died.

So, using just the Diamond Princess numbers, it looks to me like this is a highly infectious virus, but not a very lethal one.

Some people think that the virus is racially targeted, and only Chinese people can contract it. But since a Brit who doesn’t look in the least bit Chinese has tested positive, this would seem not to be true.

Other people think that the new coronavirus epidemic is just another scare. Or that lung problems and pneumonia in Wuhan are being blamed on the virus, but actually caused by air pollution. Wuhan maybe just happens to be the worst place anyone would want to be when they come down with flu.

My guess, for what it’s worth, is that this new coronavirus is being massively hyped, because the dangers of absolutely everything – from tobacco smoke to carbon dioxide – are vastly exaggerated these days. So this latest threat is also being inflated into something worse than it actually is.