From 2000 to 2009, 45 percent of carbon monoxide exposure reported by the National Poison Data System was not treated at a hospital, U.S. officials say. The Centers for Disease Control and Prevention\'s Morbidity and Mortality Weekly Report says these exposures to carbon monoxide would not have been identified by existing surveillance methods based on healthcare administrative records.The National Poison Data System of the American Association of Poison Control Centers holds more than 50 million poison exposure case records, with more than 2 million new records added each year.The system holds many types of technical medical information that is searchable in many ways, and it is the only near real-time comprehensive poisoning surveillance database in the United States.\"Carbon dioxide poisoning is a leading cause of unintentional U.S. poisoning deaths, yet it is preventable. The NPDS, a near real-time surveillance system on calls placed to the U.S. poison centers, was used to depict the burden of carbon monoxide exposures and their true health impact and cost to society more accurately,\" the report says. \"We found that the demographics of persons managed on-site for carbon monoxide exposure and those treated at a healthcare facility were similar, and that the predominant exposure location -- a person\'s home -- was similar.\" This suggests that current prevention efforts for CO poisoning, such as home installation of CO alarms, can protect individuals whether or not their poisoning is severe enough to warrant care at a healthcare facility.