What did Steve do for the SARS effort?
SARS is, by all appearances, under control in Singapore.  The Asia Research Institute and the Faculty of Science have each held workshops considering the disease and its consequences.  A number of researchers at NUS are now trying to understand the disease in all its aspects.  As news reports suggest, controlling the disease and dealing with its effects has been quite costly not to mention the significant cost in human life.

In April 2003 I began working with a small team of researchers here at NUS that had been organized by the WHO.  We worked to understand how the communicable disease spread in Singapore so that, should the disease break out again, intervention can be as swift and as effective as possible. Even if SARS does not return, the possibility of another outbreak of a communicable disease is real.

SARS has been spread directly person-to-person in Singapore.  Social contact has been critical.  Yet while the disease sometimes spread by the most fleeting contact, in other cases, more extended contact did not result in transmission.  We need to sort through quite a lot of information to sort out the reasons for the transmission and non-transmission of the disease.

As part of that effort of simplifying the available data to gain a better understanding, I worked on visualizing the information on the spread of the disease.  Two preliminary examples of our graphs are below.  These communicate the diffusion of the disease over time and the sources of infection.  The horizontal dimension to the graph is time.

These are, of course, rough copies meant for informal use. Of course, there is much more that can be visualized but these two communicate the basics.
This figure shows the uneven pace of diffusion through the end of April

This fugure shows how the cases were transmitted bwteeen persons.  Many of the cases can be traced back to a single source.

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