Scientists to use satellite imagery to predict disease outbreaks
Washington, Oct 9 : Scientists at the University of Maryland in the US are hoping to
predict disease outbreaks like cholera epidemics four to six weeks before they actually
happen, by looking a satellite imagery.
According to a report in Discovery News, the research could help save lives worldwide,
and could be used to develop other models to predict other seasonal or climate-driven
infectious diseases.
"Predicting the conditions that trigger cholera outbreaks in coastal regions could be
very valuable for public health," said Rita Colwell, a University of Maryland scientist
who has studied cholera for decades.
"If we see this coming, we could go into these areas with bottled water and medication
to save lives," she added.
Cholera, a disease that gives victims diarrhea so severe they can die 18 hours after
their first liquid stool, is caused by a bacterium, Vibrio cholerae. Humans become
infected after eating contaminated food or water.
Cholera outbreaks usually occur in developing countries, such as India, Bangladesh and
in Afica, although Colwell says that she's found the bacterium in Eastern U.S. coastal
waters as well.
Vibrio cholerae is associated with a type of crustacean called a copepod that appears
naturally in many areas of the world. The copepods feed on zooplankton, which in turn feed
on phytoplankton. Phytoplankton use photosynthesis to harvest energy from the sun to
create their food.
Colwell and her colleagues use this food ladder to their advantage. Higher sea
temperatures encourages photosynthesis. Higher sea levels brings that phytoplankton, and
later cholera, closer to humans.
Satellites can currently measure sea temperature, sea height and chlorophyll
concentrations.
Colwell hopes that future satellite data will also include information on salinity,
oxygen saturation and other variables, which could help increase the accuracy of their
models.
Colwell and her colleagues correlated the environmental data with infection statistics
in several countries to create a model that can predict the severity of cholera outbreaks
four to six weeks before the first individual is infected.
Colwell expects that within the next three to four years, her team will accurately
predict the time and size of future cholera epidemics four to six weeks before the first
individuals become ill.
According to David Hamer, an infectious disease specialist at Boston University,
"Having a tool to predict outbreaks like cholera would be very helpful to public health
authorities by making sure that adequate supplies for rehydration therapy and antibiotics
are available to treat the disease."
--ANI
