Satellite imagery shows effects of changes in land use on human health
14 July 2006
Manhattan, Kansas, USA. Analysis of satellite images of
the earth can show how land use and land cover changes caused by human
population growth and migration, and climate change affect human health and
Doug Goodin, a Kansas State University geography professor,
is using remote sensing, in combination with other types of data, to monitor
and forecast the spread of infectious disease. Goodin and other scientists
recently discussed this subject at the workshop, "Contributions of Remote
Sensing for Decisions about Human Welfare," sponsored by the National
Academies of Science in Washington, D.C.
According to Goodin, there is a
confluence of change currently taking place across the globe. The world's
population is steadily increasing, the global climate is changing and global
ecology is being altered. All are thought to be related to the emergence of
new diseases or re-emergence of old diseases, he said.
"One of the new
paradigms for looking at this kind of thing is that we try to understand the
disease as not just something that affects the human being," Goodin said.
"We also try to understand its ecological context, its physical context and
also its social context because there are certainly social human factors in
any kind of disease."
Goodin said one reason for current interest in
remote sensing is because it allows researchers to measure or note changes
in the delicate balance of ecological systems. He is using the technology to
study the re-emergence of hantavirus in the South American country of
Paraguay. The deadly rodent-borne virus is fatal 30 percent to 50 percent of
the time in humans.
"By using remote sensing technology, we've been able
to understand how human beings have changed the landscape the mice live in,"
Goodin said. "It forces different kinds of behaviour for the mice. It brings
them, perhaps, more in contact with each other, so the disease spreads
horizontally in the rodent population, and more in contact with people, so
there is a greater chance humans can contract this disease."
the reoccurrence of the hantavirus, which re-emerged in the 1990s in United
States, is evidence of the delicate balance of ecological systems and the
possibility of disease to emerge or re-emerge when those systems are
altered. He chose Paraguay to conduct his study because it is one place
where there has been significant occurrence of the disease and also because
there are several hantaviruses circulating there.
"Even though it is a
relatively small country, Paraguay is a country with tremendous ecological
contrast," Goodin said.
Goodin attributes the rapid deforestation of
Paraguay's rain forest, the Atlantic forest, as a cause for the landscape
changes. He said the Atlantic forest is more of a biodiversity hot spot than
the more famous Amazon forest. He said the forest is rapidly disappearing
because people need the land.
According to Goodin, remote sensing
technology also can be used to reduce sickness related to poor water
quality, such as diarrhoea.
"That is something we can observe with remote
sensing," Goodin said. "We can actually look at water bodies; we also can
look at the context to see where pollutants in water are coming from. Armed
with that kind of knowledge, we can actually suggest how to try to eliminate
Goodin's research project is sponsored in part by the
National Institutes of Health through the Southern Research Institute for
$1.6 million over a four-year period. NASA also has co-sponsored the
research for approximately $40,000 through its Space Grant Program.