For Submission to the Journal of Community Health: Carbon Monoxide Awareness and Detector Use in the State of Wisconsin.

Carbon monoxide (CO) is a leading cause of poisoning. CO detectors are a known-effective prevention strategy, however, little is known about use of detectors or knowledge of risk. This study assessed awareness of CO poisoning risk, detector laws, and detector use among a statewide sample. Data collected from the Survey of the Health of Wisconsin (SHOW) included a CO Monitoring module added to the in-home interview for 466 participants representing unique households across Wisconsin in 2018-2019. Univariate and multivariable logistic regression models examined associations between demographic characteristics, awareness of CO laws and detector use. Less than half of households had a verified CO detector. Under 46% were aware of the detector law. Those aware had 2.82 greater odds of having a detector in the home compared to those unaware of the law. Lack of CO law awareness may lead to less frequent detector use and result in higher risk of CO poisoning. This highlights the need for CO risk and detector education to decrease poisonings.

Lost time: COVID-19 indemnity claim reporting and results in the Wisconsin workers' compensation system from March 12 to December 31, 2020.

BACKGROUND: The COVID-19 pandemic introduced a new compensable infectious disease to workplaces. METHODS: This was a descriptive analysis of Wisconsin COVID workers' compensation (WC) claims between March 12 and December 31, 2020. The impact of the presumption law (March 12 to June 10, 2020) was also evaluated. RESULTS: Less than 1% of working-age residents with COVID-19 filed a claim. COVID-19 WC claim rates (per 100,000 FTE) were notably low for frontline industry sectors such as Retail Trade (n = 115), Manufacturing (n = 88), and Wholesale Trade (n = 31). Healthcare workers (764 claims per 100,000 FTE) comprised 73.2% of COVID-19 claims. Most claims (52.8%) were denied and the proportion of denied claims increased significantly after the presumption period for both first responders and other occupations. CONCLUSION: The presumption law made benefits accessible primarily to first responders. Further changes to WC systems are needed to offset the individual and collective costs of infectious diseases.

Development of a Pharmacist-Led Opt-Out Cessation Treatment Protocol for Combustible Tobacco Smoking Within Inpatient Settings.

Background: Although people who smoke cigarettes are overrepresented among hospital inpatients, few are connected with smoking cessation treatment during their hospitalization. Training, accountability for medication use, and monitoring of all patients position pharmacists well to deliver cessation interventions to all hospitalized patients who smoke. Methods: A large Midwestern University hospital implemented a pharmacist-led smoking cessation intervention. A delegation protocol for hospital pharmacy inpatients who smoked cigarettes gave hospital pharmacists the authority to order nicotine replacement therapy (NRT) during hospitalization and upon discharge, and for referral to the Wisconsin Tobacco Quit Line (WTQL) at discharge. Eligible patients received the smoking cessation intervention unless they actively refused (ie, "opt-out"). The program was pilot tested in phases, with pharmacist feedback between phases, and then implemented hospital-wide. Interviews, surveys, and informal mechanisms identified ways to improve implementation and workflows. Results: Feedback from pharmacists led to changes that improved workflow, training and patient education materials, and enhanced adoption and reach. Refining implementation strategies across pilot phases increased the percentage of eligible smokers offered pharmacist-delivered cessation support from 37% to 76%, prescribed NRT from 2% to 44%, and referred to the WTQL from 3% to 32%. Conclusion: Hospitalizations provide an ideal opportunity for patients to make a tobacco quit attempt, and pharmacists can capitalize on this opportunity by integrating smoking cessation treatment into existing inpatient medication reconciliation workflows. Pharmacist-led implementation strategies developed in this study may be applicable in other inpatient settings.

Improving Outreach and Surveillance Efforts Following a Large-Scale Carbon Monoxide Poisoning in Wisconsin.

OBJECTIVE: In December 2014, the largest carbon monoxide (CO) poisoning in Wisconsin's history occurred at an ice arena. Following this event, the Wisconsin Environmental Public Health Tracking (WI EPHT) Program sought to improve outreach and surveillance efforts. METHODS: WI EPHT designed and distributed educational materials on CO poisoning prevention and surveyed stakeholders to gauge the effectiveness of outreach efforts. To enhance surveillance, WI EPHT utilized data from the Wisconsin Poison Center (WPC) to generate real-time alerts of anomalous numbers of CO-related calls. RESULTS: WI EPHT found that 42% of stakeholders reviewed the outreach materials, and 1 ice arena had installed a CO detector as a result. CO alerts were developed using WPC data and are now routinely used in statewide public health surveillance. CONCLUSION: WI EPHT staff improved CO poisoning prevention outreach and saw a positive response among stakeholders. This work demonstrates ways that health agencies can improve outreach and surveillance for CO poisoning. Improvements in these areas can bolster public health response and may prevent CO-related illness and injury.

Taking Action With Data: Improving Environmental Public Health at the Community Level.

CONTEXT: The Wisconsin Environmental Public Health Tracking Program (Wisconsin Tracking) compiles and provides data on health endpoints and related environmental exposures as a resource to local health departments, tribes, academia, and other stakeholders. The goal of providing these data is that stakeholders use them to develop projects that improve environmental health in their communities-that is, moving from "data to action." OBJECTIVE: To encourage use of Wisconsin Tracking data, we developed a minigrants program and issued a funding opportunity to local health departments and tribes. The opportunity requested proposals for small projects using our data, with the goal of making public health improvements in those communities. Wisconsin Tracking evaluated the minigrants program after its completion. DESIGN/SETTING: Eight local health departments in Wisconsin were awarded up to $10 500 to develop and implement projects over a 9-month period. METHODS: Wisconsin Tracking created a funding opportunity announcement requiring utilization of our data to develop projects by local health departments in Wisconsin. We reviewed and scored applications, evaluating proposals on a range of criteria. During the 9-month project period, Wisconsin Tracking staff members provided a variety of technical assistance to grantees. An evaluation of the overall program followed. RESULTS: Funded communities used Wisconsin Tracking data to improve public health infrastructure, leverage partnerships, establish new initiatives, respond to emergencies, improve communication with stakeholders and residents, and make a variety of public health improvements in their communities. CONCLUSIONS: Efforts to increase use of our data catalyzed development of small-scale environmental health projects. This minigrants program was successful at building relationships between local health departments and Wisconsin Tracking, increasing awareness of Wisconsin Tracking data and resources, and contributing to numerous documented public health improvements throughout Wisconsin.

Exposure to Elevated Carbon Monoxide Levels at an Indoor Ice Arena--Wisconsin, 2014.

On December 13, 2014, the emergency management system in Lake Delton, Wisconsin, was notified when a male hockey player aged 20 years lost consciousness after participation in an indoor hockey tournament that included approximately 50 hockey players and 100 other attendees. Elevated levels of carbon monoxide (CO) (range = 45 ppm-165 ppm) were detected by the fire department inside the arena. The emergency management system encouraged all players and attendees to seek medical evaluation for possible CO poisoning. The Wisconsin Department of Health Services (WDHS) conducted an epidemiologic investigation to determine what caused the exposure and to recommend preventive strategies. Investigators abstracted medical records from area emergency departments (EDs) for patients who sought care for CO exposure during December 13-14, 2014, conducted a follow-up survey of ED patients approximately 2 months after the event, and conducted informant interviews. Ninety-two persons sought ED evaluation for possible CO exposure, all of whom were tested for CO poisoning. Seventy-four (80%) patients had blood carboxyhemoglobin (COHb) levels consistent with CO poisoning; 32 (43%) CO poisoning cases were among hockey players. On December 15, the CO emissions from the propane-fueled ice resurfacer were demonstrated to be 4.8% of total emissions when actively resurfacing and 2.3% when idling, both above the optimal range of 0.5%-1.0%. Incomplete fuel combustion by the ice resurfacer was the most likely source of elevated CO. CO poisonings in ice arenas can be prevented through regular maintenance of ice resurfacers, installation of CO detectors, and provision of adequate ventilation.

Using environmental public health tracking to identify community targets for public health actions in childhood lead poisoning in Wisconsin.

OBJECTIVE: In an effort to improve the ability of local public health departments to target resources to the highest need regions, the Wisconsin Environmental Public Health Tracking (WI EPHT) Program worked to enhance its public portal to benefit the Wisconsin Childhood Lead Poisoning Prevention Program (WCLPPP) and other programs. The WI EPHT Program conducted this enhancement in collaboration with WCLPPP. DESIGN/SETTING: The WI EPHT enhanced public portal is the next phase of Wisconsin's ongoing efforts in environmental public health tracking. As part of this process, this new mapping application includes mapping capacity that provides information on childhood lead testing and results at county and census tract levels in Wisconsin. METHODS: The WI EPHT Program will update its public portal to have the capability to map data at a subcounty level (ie, census tract or zip code) for some data topics when such data are available. RESULTS: This tool is available to local public health departments and other public health organizations throughout Wisconsin as a resource to identify communities most affected by the Centers for Disease Control and Prevention's new guidelines with regard to childhood lead poisoning. CONCLUSIONS: The collaboration between WI EPHT and WCLPPP on updating and enhancing the portal exemplifies the power of environmental health data to inform a more accurate understanding of public health problems.

Parental depressive symptoms and childhood cancer: the importance of financial difficulties.

PURPOSE: Research suggests a relationship between caring for a child with cancer and psychological distress in caregivers. Less evident is the role which financial difficulties might play in this relationship. We sought to determine if caring for a child with cancer was related to clinically relevant depressive symptoms among parents, whether or not financial difficulties mediated this relationship, and if financial difficulties were independently associated with symptoms of depression among parents of children with cancer. METHODS: Data are from 215 parents of children diagnosed with cancer or brain tumors (n = 75) and a comparison group of parents of healthy children (n = 140). Multiple logistic regression analyses were used to assess the factors associated with reporting clinically relevant depressive symptoms. RESULTS: Caring for a child with cancer was associated with increased odds of clinically relevant depressive symptoms in parents (OR = 4.93; 95 % CI 1.97-12.30), controlling for covariates. The mediating effect of financial burden on this relationship was not statistically significant. However, among parents of children with cancer, negative financial life events increased the likelihood of reporting symptoms of depression (OR = 4.89; 95 % CI 1.26-18.96). CONCLUSIONS: Caring for a child with cancer was associated with depressive symptoms for parents. Financial difficulties were the strongest correlate of these symptoms among parents of children with cancer. Our results suggest that it may not only be the burden of caring for the child with cancer but also the associated financial difficulties that contribute to a higher likelihood of depressive symptoms in parents.

Long COVID Among Wisconsin Workers in the Workers' Compensation System: Associations With Sociodemographics, Vaccination, and Predominant Variant Period From March 1, 2020 to July 31, 2022.

OBJECTIVE: This analysis aimed to determine the likelihood of developing long COVID among Wisconsin workers while adjusting for sociodemographics, COVID-19 vaccination, industry, and occupation. METHODS: This retrospective analysis determined the odds ratios of developing long COVID among Wisconsin workers who were compensated for COVID-19 lost time during March 1, 2020 to July 31, 2022. RESULTS: A total of 234 workers (11.7%) were determined to have long COVID. Factors associated with long COVID were age ≥40 years, non-White race, infection occurrence during the initial and Omicron variant dominant periods, and the absence of COVID-19 vaccination. Workers in manufacturing and public administration were more likely to develop long COVID compared with those in health care and social assistance. CONCLUSIONS: Long COVID disproportionately affects some worker groups. This calls for more worker protection and preventative care to mitigate its impact.

Look local: the value of cancer surveillance and reporting by American Indian clinics.

INTRODUCTION: Cancer incidence and mortality rates for American Indians in the Northern Plains region of the United States are among the highest in the nation. Reliable cancer surveillance data are essential to help reduce this burden; however, racial data in state cancer registries are often misclassified, and cases are often underreported. METHODS: We used a community-based participatory research approach to conduct a retrospective ascertainment of cancer cases in clinic medical records over a 9-year period (1995-2003) and compared the results with the state cancer registry to evaluate missing or racially misclassified cases. Six tribal and/or urban Indian clinics participated in the study. The project team consisted of participating clinics, a state cancer registry, a comprehensive cancer center, an American Indian/Alaska Native Leadership Initiative on Cancer, and a set of diverse organizational partners. Clinic personnel were trained by project staff to accurately identify cancer cases in clinic records. These records were then matched with the state cancer registry to assess misclassification and underreporting. RESULTS: Forty American Indian cases were identified that were either missing or misclassified in the state registry. Adding these cases to the registry increased the number of American Indian cases by 21.3% during the study period (P = .05). CONCLUSIONS: Our results indicate that direct reporting of cancer cases by tribal and urban Indian health clinics to a state cancer registry improved the quality of the data available for cancer surveillance. Higher-quality data can advance the efforts of cancer prevention and control stakeholders to address disparities in Native communities.

Work and Life in the Balance: COVID-19 Mortality by Usual Occupation and Industry in Wisconsin.

INTRODUCTION: Work is central to the discourse surrounding the pandemic. Going to work during the COVID-19 pandemic put individuals at risk for both disease and death. This study assesses COVID-19 mortality by industry and occupation for working-age adults in Wisconsin and applies a health equity lens to understand COVID-19, demographics, work, and mortality in the state. METHODS: We used vital records data to evaluate COVID-19 mortality in Wisconsin. We assessed the demographics of working-age decedents using chi-square tests and logistic regression. We also classified decedents by usual occupation with Standard Occupational Classification (2018) and North American Industry Classification System (2017) codes to calculate mortality rates. We then calculated proportional mortality ratios to evaluate if mortality rates from COVID-19 in industry or occupation groups were significantly higher than the overall (ie, average) mortality rate from COVID-19 among all working-age Wisconsin adults. RESULTS: Both Asian/Pacific Islander and Hispanic individuals in Wisconsin had elevated likelihoods of dying from COVID-19. Lower levels of education also were associated with a higher likelihood of COVID-19-attributable death. Additionally, we found several occupations and industries that had elevated mortality rates from COVID-19. Proportional mortality ratios showed higher than expected mortality for several occupations including Protective Service; Office and Administrative Support; Farming, Fishing, and Forestry; and Installation, Maintenance, and Repair. Moreover, several industries had elevated proportional mortality ratios, including Agriculture, Forestry, Fishing, and Hunting; Finance and Insurance; Transportation and Warehousing; and Public Administration. DISCUSSION: The lessons of the pandemic are important for public health and worker safety. Understanding who bears disparate risks allows us to prepare, communicate, and mitigate risk.

Incidence of COVID-19 and Worker's Compensation Utilization Among Food Manufacturing in Wisconsin, October 1, 2020 - December 31, 2021.

BACKGROUND: The food manufacturing industry is a critical economic sector and has been a high-risk industry for COVID-19. This analysis aimed to describe COVID-19 cumulative case incidence rates among Wisconsin food manufacturing workers and their worker's compensation utilization. METHODS: This was a descriptive analysis of COVID-19 cases among food manufacturing industry workers in Wisconsin from October 1, 2020, through December 31, 2021. RESULTS: Occupations with the highest cumulative case incidence rate (per 1000 workers) were Packers and Packagers, Hand (275; 95% CI, 252-300), Packaging and Filling Machine Operators and Tenders (266; 95% CI, 254-277), and Laborers and Freight, Stock and Material Movers, Hand (261; 95% CI, 247-276). Two worker's compensation claims were paid to food manufacturing workers. DISCUSSION: Wisconsin food manufacturing workers were disproportionately affected by COVID-19, with a high cumulative case incidence rate exceeding that of the manufacturing industry overall, statewide non-institutionalized working-age adults, and the ambulatory health care industry. There was also a disproportionately low use of worker's compensation benefits in Wisconsin compared to the high COVID-19 disease incidence. Improved worker protections for occupational infectious diseases with high risk of transmission are needed as well as improvements to the worker's compensation system.

Increased Alcohol-Related Mortality in Wisconsin Pre-COVID: A Two-Decade Trend.

INTRODUCTION: Alcohol-related mortality is increasing nationally, but state-specific trends still need to be explored. This paper reviews the patterning of alcohol-related deaths among Wisconsin residents in the 2 decades prior to the COVID-19 pandemic. METHODS: Data are from death certificates for state residents from 2000 through 2019. We used underlying cause of death codes (ICD-10) to classify deaths as 100% attributable to alcohol (ie, acute, chronic liver, and other chronic). Demographic characteristics were available for the most recent decedents (2015-2019). We assess trends in alcohol-related mortality and used chi-square tests to assess demographic differences compared to deaths from all other causes. RESULTS: The number of alcohol-related deaths more than doubled from 2000 through 2019 in Wisconsin, rising from 394 in 2000 to 857 in 2019. In the 5 most recent years (2015-2019), the populations with significantly higher rates of alcohol-related deaths included men, middle-aged adults, Black residents, and those of Hispanic descent. Education level also was significantly related to alcohol-attributable mortality, as those with the highest and lowest education levels were the least likely to die from this cause. DISCUSSION/CONCLUSIONS: Results of these analyses show that the number of deaths due to alcohol-related diseases has risen significantly since 2000, and this trend preceded the COVID-19 pandemic. These rising mortality rates deserve the attention of the medical and public health communities. Our findings show that, in recent years, Hispanic individuals, men, and middle-aged adults are at a higher risk for alcohol-related deaths. Stakeholders may wish to consider interventions targeted to these groups.

Can inpatient pharmacists move the needle on smoking cessation? Evaluating reach and representativeness of a pharmacist-led opt-out smoking cessation intervention protocol for hospital settings.

PURPOSE: Hospitalization affords an opportunity to reduce smoking, but fewer than half of patients who smoke receive evidence-based cessation treatment during inpatient stays. This study evaluated a pharmacist-led, electronic health record (EHR)-facilitated opt-out smoking cessation intervention designed to address this need. METHODS: Analyses of EHR records for adult patients who smoked in the past 30 days admitted to an academic medical center in the upper Midwest were conducted using the Reach Effectiveness Adoption Implementation Maintenance (RE-AIM) framework. The reach of a pharmacist-led, EHR-facilitated protocol for smoking cessation treatment was assessed by comparing patients' receipt of nicotine replacement therapy (NRT) and tobacco quitline referral before and after implementation. χ2 tests, t tests, and multiple logistic regression models were used to compare reach across patient demographic groups to assess treatment disparities and the representativeness of reach. Adoption of the program by hospital services was also assessed. RESULTS: Of the 70 hospital services invited to implement the program, 88.6% adopted it and 78.6% had eligible admissions. Treatment reach increased as rates of delivering NRT rose from 43.6% of eligible patients before implementation to 50.4% after implementation (P < 0.0001) and quitline referral rates rose from 0.9% to 11.9% (P < 0.0001). Representativeness of reach by sex and ethnicity improved after implementation, although disparities by race and age persisted after adjustment for demographics, insurance, and primary diagnosis. Pharmacists addressed tobacco use for eligible patients in 62.5% of cases after protocol implementation. CONCLUSION: Smoking cessation treatment reach and representativeness of reach improved after implementation of a proactive, pharmacist-led, EHR-facilitated opt-out smoking cessation treatment protocol in adult inpatient services.

An observational study of the secondary effects of a local smoke-free ordinance.

INTRODUCTION: The secondary, sometimes unintended effects of smoke-free ordinances have not been thoroughly evaluated. In this observational study, we evaluated the association of a local ordinance implemented in Madison, Wisconsin, with changes in public disturbances; smoking, drinking, and bar-going behaviors in the general population; and smoking and drinking behaviors among university students. METHODS: We obtained data from 4 sources: police records, key informant interviews, a community survey, and an undergraduate survey. Except for interviews, which we conducted postenactment only, we compared measures before and after the ordinance was put into effect. RESULTS: We found no evidence of association of the ordinance with public disturbances. We found that the ordinance was not associated with changes in smoking rates, drinking rates, or bar-going in the general population, although bar-going decreased among the 16% of the general adult population who smokes (from 84% in 2005 to 70% in 2007, P < .001). Student smoking rates also decreased (from 23% in 2005 to 16% in 2007, P < .001), but student binge drinking did not change. CONCLUSION: The study adds unique information to the evidence base on the effect of smoke-free policies, finding little evidence of their secondary, unintended effects. With the addition of these results to existing evidence, we conclude that the potential health benefits of smoke-free ordinances outweigh the potential harms from unintended effects.

Cancer health disparities persist among African Americans in Wisconsin.

BACKGROUND: Cancer incidence and mortality rates have decreased over the last few decades, yet not all groups have benefited equally from these successes. This has resulted in increased disparities in cancer burden among various population groups. OBJECTIVE: This study examined trends in absolute and relative disparities in overall cancer incidence and mortality rates between African American and white residents of Wisconsin during the period 1995-2006. METHODS: Cancer incidence data were obtained from the Wisconsin Cancer Reporting System. Mortality data were accessed from the National Center for Health Statistics' public use mortality file. Trends in incidence and mortality rates during 1995-2006 for African Americans and whites were calculated and changes in relative disparity were measured using rate ratios. RESULTS: With few exceptions, African American incidence and mortality rates were higher than white rates in every year of the period 1995-2006. Although cancer mortality and incidence declined for both groups over the period, relative racial disparities in rates persisted over the period and account for about a third of African American cancer deaths. CONCLUSIONS: Elimination of cancer health disparities will require further research into the many contributing factors, as well as into effective interventions to address them. In Wisconsin, policymakers, health administrators, and health care professsionals need to balance resources carefully and set appropriate priorities to target racial inequities in cancer burden.

Carbon monoxide detector effectiveness in reducing poisoning, Wisconsin 2014-2016.

Introduction: Carbon monoxide (CO) is a colorless, odorless, and nonirritating gas. The most common exposures are from gas powered appliances such as furnaces, water heaters, stoves, and vehicles. To prevent poisoning, CO detectors with audible alarms were developed. This study aims to evaluate the effectiveness of CO detectors in reducing poisoning in Wisconsin.Methods: Records were queried from National Poison Data System for unintentional CO exposures that occurred in residences in Wisconsin during 2014-2016 (N = 703). After applying sample exclusion criteria, notes were abstracted for cases where CO detector use was mentioned (n = 408). Logistic regression analyses were used to assess the association between having a CO detector alarm and CO poisoning. Linear regression analyses were used to assess the relationship between having a CO detector alarm and poisoning severity.Results: In logistic models, odds of CO poisoning were 3.2 times higher (95% CI: 1.5, 6.9) among those who had no CO detector compared to those who had a CO detector that alarmed. In linear models, not having a CO detector was associated with a 0.34 point (95% CI: 0.17, 0.54) change in outcome severity score compared to having a CO detector that alarmed.Discussion: Individuals who were exposed to CO in the absence of a CO detector were more likely to be poisoned and to have more severe medical outcomes than those that had a CO detector that alarmed.

Exposures to Opioids Among Wisconsin Children and Adolescents, 2002-2016.

BACKGROUND: Opioid overdoses and opioid-related fatalities have increased dramatically in Wisconsin over the past decade. The observed rise in morbidity and mortality parallels increased opioid prescribing and greater use of illicit drugs such as heroin. Increased availability of both prescription and illicit opioids may increase the risk of exposure and overdose among the pediatric population. METHODS: We examined demographics and temporal trends in opioid exposures among children aged 0-19 years using hospital encounter and Wisconsin Poison Control Center (WPC) data. Exposures were categorized by type of opioid. RESULTS: We identified 3,320 WPC calls and 2,725 hospital encounters involving opioids during 2002-2016. Within the hospital encounter data, the rate of opioid-involved exposures increased significantly in children aged 0-5 years and adolescents aged 13-19 years. The majority of opioid-related hospital encounters involved prescription opioids. However, the proportion of hospital encounters involving heroin increased significantly among 13-19 year olds from 2002-2016. Within WPC data, the proportion of calls involving tramadol increased among 0-5 year olds and 13-19 year olds. However, calls about opioid/acetaminophen combinations decreased significantly as a proportion of opioid exposures. DISCUSSION: These findings suggest the need for caregiver education regarding safe storage and disposal of prescription opioids to prevent unintentional or intentional exposure to these substances among young children and adolescents. Overdose rates among teens continue to rise and an increasing proportion are due to heroin; comprehensive treatment and prevention strategies targeting this demographic are needed.

Carbon Monoxide Exposure and Poisoning Cases in Wisconsin, 2006-2016.

INTRODUCTION: Carbon monoxide (CO) poisoning is responsible for over 450 deaths and 21,000 Emergency Department visits annually in the United States. In Wisconsin, multiple large-scale CO poisoning events have occurred in recent years. This analysis explores trends in CO exposure events in the state from 2006 through 2016. METHODS: Wisconsin Poison Center (WPC) CO exposure data from January 1, 2006 through December 31, 2016 was analyzed for trends over time. CO poisoning cases were classified using the Council of State and Territorial Epidemiologists case definition. RESULTS: During the study period, 3,703 persons were exposed to CO and 2,148 were poisoned. On average, 337 persons were exposed annually over this period, with an annual average of 195 suspected and probable poisoning cases per year, as reported to the WPC. Large-scale events ( ≥ 5 persons) accounted for 4.8% (n = 104) of all events. Using data extracted from WPC case notes for large-scale exposures, the most common source of exposure was furnaces or water heaters (20.2%; n = 21) followed by fire (8.7%; n = 9). CONCLUSIONS: Despite public health efforts to reduce CO exposures, CO poisoning continues to affect Wisconsin residents. Efforts to prevent large scale CO poisonings should focus on awareness of CO exposure within the home, as well as the risk in public or occupational settings. Moreover, these efforts should focus on improving the use of CO detectors in all settings to prevent exposure. The WPC can be used as a resource for clinicians in cases of CO exposure and poisoning.