Joi Ito's Web

Joi Ito's conversation with the living web.

A few quotes from the proMED-mail, which is a good list to follow for on-the-ground updates from the global medical community.
Date: 4 Apr 2003
From: ProMED-mail
Source: OIE press release
Atypical pneumonia: Severe acute respiratory syndrome (SARS)

The causative agent has not yet been identified. It appears to be a Paramyxovirus, a Coronavirus, or a mixture. The World Health Organization (WHO) has hypothesised that the causative virus(es) may be of animal origin, from domestic or wild animals located in Guangdong Province (in South China).

This is why the World Organisation for Animal Health (OIE) has contacted the Chinese Veterinary Authorities to obtain information on the animal health situation in China over the past 6 months and, in particular, in Guangdong Province.

Date: Fri 4 Apr 2003
From: Steve Berger

SARS - Deja vu ?

As SARS enters its fifth month, a number of questions remain unanswered. Why Asia? Why now? Why young adults? To these I would add a fourth question (Why the panic?) and an hypothesis.

Every 10 years or so, a pandemic spreads out from China and surrounding countries. The 'Asian flu' of 1957 claimed 98 000 lives worldwide, and the 'Hong Kong flu' of 1968 an additional 45 000 lives. Although the world community was rightly concerned, I do not recall a collapse of air travel, imposition of quarantine, or daily front-page headlines. To date, SARS has claimed 79 lives, and the etiological agent appears to be far less contagious than Influenza A virus.


Folks -- most new 'killer' diseases come from animals. The technical term is 'zoonoses'.

The reason zoonotic diseases are so virulent and occasionally fatal to humans, is because they've "optimized" themselves for their "host" animal's biology; what works well for a disease in chickens for example, may be fatal to humans.

Occasionally, these diseases mutate into a human-infectious form, hence the danger.

Non-zoonotic diseases have, by contrast, been living in humans for thousands of years, and have "optimized" themselves to keep their hosts *alive*. A successful disease does not kill, as that means their food source is no more ;)

BTW the reason these have recently been originating in China and other Asian countries, is due to the prevalence of live fowl being sold in markets, combined with high-density housing and work environments, apparently. The density of fowl and humans provides lots of opportunity for a mutated microbe to make that jump and infect humans, who then live and work in close proximity to a lot more humans, which provides a path to infect more humans quickly.

This is all AFAIK -- my girlfriend's a biologist who did a little work in the field in the past...

How does sars come from animals

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Joi Ito questions the panic around SARS. I have to say, I am perplexed also. It seems to me that 79 people worldwide is hardly something to get worked up about - maybe the threat of "biological weapons" and nasty... Read More