Carbon Monoxide: The statistical data

Facts about carbon monoxide poisoning:

Most signs and symptoms of CO exposure are nonspecific (e.g., headache or nausea) and can be mistakenly attributed to other causes, such as viral illnesses. Undetected or unsuspected CO exposure can result in death. – Morbidity and Mortality Weekly Report

The true incidence of CO poisoning is not known, since many non-lethal exposures go undetected. It has been estimated that one-third of all cases of CO poisoning are undiagnosed. – The Internet Journal of Emergency & Intensive Care Medicine

During 2001–2003, an estimated 15,200 persons with confirmed or possible non–fire-related CO exposure were treated annually in hospital EDs. In addition, during 2001–2002, an average of 480 persons died annually from non–fire-related CO poisoning. – Morbidity and Mortality Weekly Report

The nonfatal rate for CO exposure was highest for children aged under 4 years (8.2 per 100,000 population), whereas the CO death rate was highest for adults aged over 65 years (0.32). Adults aged over 65 years accounted for 23.5% of CO poisoning deaths. – Morbidity and Mortality Weekly Report

The annualized incidence of fatal and nonfatal CO exposures occurred more often during the fall and winter months, with the highest numbers occurring during December (56 fatal and 2,157 nonfatal exposures) and January (69 fatal and 2,511 nonfatal exposures). The annualized incidence was substantially lower during the summer months, with 21 fatal and 510 nonfatal exposures occurring during June and 22 fatal and 524 nonfatal exposures occurring during July. – Morbidity and Mortality Weekly Report

The majority (64.3%) of nonfatal CO exposures were reported to occur in homes; 21.4% occurred in public facilities and areas. – Morbidity and Mortality Weekly Report

CO from motor-vehicle exhausts is the single most common cause of poisoning deaths in the United.10 Of the 11,547 unintentional CO deaths during 1979-1988, 57% were caused by motor vehicle exhausts; of these 83% were associated with stationary vehicles. Most motor-vehicle-related CO deaths in garages have occurred even though the garage doors or windows have been open, suggesting that passive ventilation may not be adequate to reduce risk in semi-closed spaces. Smoke inhalation from all types of fires is the second leading cause of CO poisoning. Most immediate deaths from building fires are due to CO poisoning and therefore, fire fighters are at high risk. – The Internet Journal of Emergency & Intensive Care Medicine

…men and adults aged over 65 years were more likely to die from CO poisoning than other persons. The higher rate in men has been attributed to high-risk behaviors among men, such as working with fuel-burning tools or appliances. The higher rate among older persons has been attributed to the likelihood of older adults mistaking symptoms of CO poisoning for other conditions common among persons in this age group (e.g., influenza-like illnesses or fatigue). CO deaths were highest during colder months, likely because of increased use of gas-powered furnaces and use of alternative heating and power sources used during power outages, such as portable generators, charcoal briquettes, and propane stoves or grills. – Morbidity and Mortality Weekly Report

The most common symptoms experienced were headache (37.5%), dizziness (18.0%), and nausea (17.3%). Severer symptoms were reported less often, including loss of consciousness (7.7%), shortness of breath (6.7%), and loss of muscle control (3.5%). According to medical records, 9.3% of patients in the NEISS-AIP sample reported that they had a CO detector at home, and 100% of those indicated that the detector had alerted them to the presence of CO. – Morbidity and Mortality Weekly Report

Many victims of CO poisoning die or suffer permanent, severe neurological injury despite treatment. In addition, as many as 50% of those who recover consciousness and survive may experience varying degree of more subtle but still disabling neuropsychiatric sequela. – The Internet Journal of Emergency & Intensive Care Medicine