Experts call for computer imaging to halt outbreaks

HONG KONG, June 27 (Reuters) Experts today called for the use of computer imaging to track the spread of disease, such as bird flu, saying it can be used to identify areas of outbreaks so they can be ringfenced.

The technology, geographic information system (GIS), can be used to chart detailed maps showing exact locations of residential and office buildings, produce markets, chicken farms and any other sites where infections might have occurred.

''Anytime there is a new disease, the important thing is to georeference that information ... where do the victims live, where might the exposure have taken place, did it take place at home, at work or recreationally?'' said Charles Croner of the U S Centers for Disease Control and Prevention (CDC).

''If flu cases continue to appear in the medical system, then we start to get a pattern of its existence.'' ''We must immediately put in resources to stop the flu. We must remediate it, we must give out vaccines to people who might have been exposed to these people. The geography is crucial,'' he told reporters on the sidelines of a conference on GIS.

Although the H5N1 avian flu virus remains predominantly a disease among birds, the medical community has warned it can trigger a pandemic if it mutates to spread efficiently among people.

There have been a few cases of limited transmission among humans but genetic analyses of the virus by the World Health Organisation and the CDC has not shown any of the traits known to help the virus spread more easily among people.

Croner said GIS was badly needed in countries such as China, Vietnam and Indonesia where the virus is now endemic.

''The WHO is very concerned about the use of this technology so it can help improve disease detection,'' he said.

GIS is the science of capturing, managing, analysing and displaying all forms of geographically referenced information.

The WHO has recommended that the technology be used to analyse epidemiological data and trends that would be more difficult to discover in tabular format.

GIS was used in Hong Kong in 2003, when it was struck by Severe Acute Respiratory Syndrome, or SARS, which killed almost 300 people in the territory.

Lai Poh Chin, associate professor of geography at the University of Hong Kong, said the technology can be used to predict the spread of an epidemic.

''Based on the mean centre, you can track its movement and see it going in a certain direction,'' Lai told Reuters.

''This technology (helps) ascertain where cases are and (allows for) fast intervention.'' REUTERS SHB HT1600