Per- and polyfluoroalkyl substances: using comparative medicine to understand exposure and adverse health outcomes in people and their pets.

One of the important human health benefits of keeping pets may be to serve as an early warning system for indoor childhood exposure to toxic chemicals such as per- and polyfluoroalkyl substances (PFAS). The stain-resistant properties and environmental stability of PFAS make them a preferred choice for protective coatings and lubricants, and they have been used for years in various manufacturing and industrial processes around the world. Although the use of PFAS has arguably improved many commercial products, they have been linked to adverse health outcomes such as developmental delays, liver damage, immune suppression, disruption of endocrine and reproductive systems, and some cancers. The current body of literature suggests that serum PFAS levels in dogs and cats are analogous to their human counterparts and that household pets experience similar changes in blood chemistry markers. The proximity of small children and household pets to PFAS-treated carpets and floors, in addition to their tendency to put things into their mouths, potentially allows pets to serve as sentinels for household PFAS exposure. To assess the suitability of pets as indicators for exposure, researchers need to understand the most likely sources of PFAS exposure for household pets and identify the biomarkers of biological effects in those animals. Understanding these parameters may alert veterinary clinicians to potential sources of contamination in the home and ultimately protect the lives of the children and animals who live there.

Current per- and polyfluoroalkyl substance (PFAS) research points to a growing threat in animals.

Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that are colorless, odorless, and oil and water repellent. Their widespread use in manufacturing and industrial processes has resulted in environmental contamination found across the world. Exposure to PFAS can lead to a variety of adverse human health outcomes such as increased cholesterol, liver damage, immune suppression, and disruption of endocrine and reproductive systems. Exposure to this family of chemicals is considered a significant public health threat. Though nearly every human and animal around the world has been exposed, most of what is known regarding health effects and toxicological processes of PFAS in animals stems from human epidemiological and laboratory animal studies. Discoveries of PFAS contamination on dairy farms and concerns for companion animals have increased interest in PFAS research related to our veterinary patients. In the limited studies published to date, PFAS has been demonstrated in serum, liver, kidneys, and milk of production animals and has been linked to changes in liver enzymes, cholesterol levels, and thyroid hormones in dogs and cats. This is further addressed in the companion Currents in One Health by Brake et al, AJVR, April 2023. There is a gap in understanding the routes of exposure, absorption of PFAS, and adverse health effects among our veterinary patients. The purpose of this review is to summarize the current literature on PFAS in animals and discuss the implications for our veterinary patients.

Antimicrobial-resistant non-typhoidal Salmonella enterica prevalence among poultry farms and slaughterhouses in Chitwan, Nepal.

BACKGROUND AND AIM: Antibiotic-resistant infections are one of the leading threats to public health globally. Indiscriminate use of antibiotics in food animal production is an important driver of resistance, particularly among foodborne pathogens such as non-typhoidal Salmonella enterica (NTS). While there has been extensive research on antimicrobial-resistant (AMR) S. enterica in India and China, there have been few studies in countries in South Asia, including Nepal. This is particularly important with the rise of commercial poultry farming in Nepal as a means of economic development and nutritional subsistence. This descriptive study seeks to identify the prevalence and resistance patterns of NTS serotypes focusing on Chitwan, Nepal's leading poultry producing district. MATERIALS AND METHODS: A mixture of purposive and judgment sampling of 18 poultry farms and 20 slaughterhouses representing a broad geographic distribution across multiple municipalities in Chitwan was conducted in May 2019. Environmental samples taken from poultry farms included: Water, litter, feces, feed, farm swabs, and eggshell swabs. Biological samples taken from nearby slaughterhouses included: Muscle, heart, liver, skin, cecum, crop, and spleen. Samples were cultured and tested for the presence of NTS. Positive isolates were serotyped and tested for antimicrobial susceptibility to seven antibiotics known to be important to both human and animal health regionally. Farm practices were also characterized through a survey, the results of which are detailed in the accompanying paper. RESULTS: Out of 708 samples (288 environmental and 420 biological), 103 (15%) tested positive for NTS (9% of environmental; n=26, 18% of biological; n=77). The percentage of positive environmental and biological samples varied by source. Environmental sample positive rates were water (27.5%), feces (10.6%), litter (8.6%), farm swabs (5%), feed (1.8%), and eggshells (0%). Biological sample positive rates were skin (28%), heart (23%), crop (20%), muscle (15%), liver (15%), spleen (15%), and cecum (12%). Out of 103 positive S. enterica isolates, 48.5% were identified as Salmonella Typhimurium, 35% Salmonella Enteritidis, 7.8% Salmonella Gallinarum, 4.9% Salmonella Virchow, and 3.9% were Salmonella Agona. Of the 103 positive isolates, 80 (78%) were resistant to at least one antibiotic, and 21 (20%) were multidrug-resistant (MDR). CONCLUSION: NTS is highly prevalent among Chitwan's growing poultry industry with higher rates of positivity found in slaughterhouse samples compared with environmental samples from farms. In addition, a high rate of AMR (78%) was revealed, and an extremely concerning number of those were shown to be MDR (20%). This baseline data has important implications for poultry production and consumption in the region. Further research will elucidate the extent to which this contamination and drug resistance is impacting the health of the local population and help inform treatment and management strategies.Note: The characterization of the poultry industry and practices that might be linked to NTS contamination in the Chitwan district are detailed in the previous paper in this series (www.veterinaryworld.org/Vol.14/February-2021/14.pdf).

Prevalence of non-typhoidal Salmonella and risk factors on poultry farms in Chitwan, Nepal.

BACKGROUND AND AIM: Poultry is becoming an increasingly important source of protein in the Nepalese diet. The Chitwan region of Nepal is the hub of the emerging poultry industry. Little is known about the prevalence of non-typhoidal Salmonella (NTS) on poultry farms or the role of farm management practices that may contribute to the presence of NTS on farms. The role of poultry in the transmission of Salmonella enterica to humans is also poorly defined. This descriptive study seeks establish baseline data through estimation of the prevalence of NTS on broiler and layer operations in various farms of the Chitwan district of Nepal. MATERIALS AND METHODS: Based on district documents on poultry production and meat marketing, a purposive sampling of 18 commercial poultry farms comprising ten broilers farms and eight layers farms was conducted. Environmental samples including water, litter, feces, feed, farm, and eggshell swabs were randomly collected from each farm. Samples were cultured and tested for the presence of NTS; positives were serotyped, and antimicrobial susceptibility determined. A comprehensive farm and practice questionnaire was administered to each farm manager. RESULTS: The farm level point prevalence rate was 55% (10 of 18 farms) for S. enterica. Of the total 288 farm environmental samples collected, 26 samples (9%) were positive. The rate of isolation varied according to the origin of samples: Water (27.5%), feces (10.6%), litter (8.6%), farm swabs (5%), feed (1.8%), and eggshells (0%). Farm management variables/risk factors are summarized and categorized as non-modifiable and modifiable for analysis. Broiler operations were more likely to be positive than layer operations as were poultry houses with two or less open sides. All-in/all-out management style was found to be protective. Due to the small sample size (18 farms), no associations reached statistical significance. CONCLUSION: Based on environmental sampling results, NTS is highly prevalent on the poultry farms in the Chitwan district of Nepal. Certain risk factors are associated with finding NTS on farms. Our findings are generally in agreement with other studies in similar countries with rapidly emerging poultry industries. The identification of risk factors provides owners, technicians, and veterinarians with some guidance to help reduce the prevalence of NTS on farms. This baseline data are critical to understanding the epidemiology of zoonotic strain of NTS in the region and are necessary for the design of future studies and mitigation plans and underlines the need for a one-health approach to protect public health-related to Salmonella spp. from poultry farms.

Public health surveillance for methicillin-resistant Staphylococcus aureus: comparison of methods for classifying health care- and community-associated infections.

OBJECTIVES: We compared 3 methods for classifying methicillin-resistant Staphylococcus aureus (MRSA) infections as health care associated or community associated for use in public health surveillance. METHODS: We analyzed data on MRSA infections reported to the Michigan Department of Community Health from October 1, 2004, to December 31, 2005. Patient demographics, risk factors, infection information, and susceptibility were collected for 2151 cases. We classified each case by the health care risk factor, infection-type, and susceptibility pattern methods and compared the results of the 3 methods. RESULTS: Demographic, clinical, and microbiological variables yielded similar health care-associated and community-associated distributions when classified by risk factor and infection type. When 2 methods yielded the same classifications, the overall distribution was similar to classification by 3 methods. No specific combination of 2 methods was superior. CONCLUSIONS: MRSA categorization by 2 methods is more accurate than it is by a single method. The health care risk factor and infection-type methods yield comparable classification results. Accuracy is increased by using more variables; however, further research is needed to identify the optimal combination.

Vancomycin-resistant Staphylococcus aureus, Michigan, USA, 2007.

Vancomycin-resistant Staphylococcus aureus (VRSA) infections, which are always methicillin-resistant, are a rare but serious public health concern. We examined 2 cases in Michigan in 2007. Both patients had underlying illnesses. Isolates were vanA-positive. VRSA was neither transmitted to or from another known VRSA patient nor transmitted from patients to identified contacts.

Demographic and urban environmental variables associated with dog bites in Detroit.

OBJECTIVE: To identify demographic and urban environmental variables associated with prevalence rates of dog bites per zip code in Detroit. DESIGN: Retrospective ecological study. SAMPLE: 6,540 people who visited any 1 of 15 hospital emergency rooms in the 29 zip codes in Detroit between January 1, 2006, and December 31, 2013, with a primary complaint of dog bite. PROCEDURES: The number of dog bites over the study period was determined per zip code. Data for the human population in each zip code in 2011 and demographic and urban environmental variables were obtained from federal, state, and municipal databases. The prevalence rate of dog bites in each zip code was calculated, and regression analysis was used to identify variables associated with this outcome. RESULTS: Results of multivariate analysis indicated that demographic variables (eg, gender, age, and education) accounted for 23.2% (adjusted R2 = 0.232) of the variation in prevalence rates of dog bites per zip code, whereas urban environmental variables (eg, blight, crime with weapons, and vacancy rate) accounted for 51.6% (adjusted R2 = 0.516) of the variation. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that demographic variables had poor association with variation in prevalence rates of dog bites per zip code, whereas urban environmental variables, particularly crime, vacancy rate, and blight, were better associated. Thus, public health and education policies need to address these urban environmental issues to lower the prevalence of dog bites in distressed urban areas.

Epidemiological Study of Mycobacterium bovis Infection in Buffalo and Cattle in Amazonas, Brazil.

Bovine Tuberculosis (BTB) is an endemic disease in about one hundred countries, affecting the economy causing a decrease in productivity, condemnation of meat, and damaging the credibility on international trade. Additionally, Mycobacterium bovis the major causative agent for BTB can also infect humans causing a variety of clinical presentations. The aim of this study was to determine BTB prevalence and the main risk factors for the Mycobacterium bovis prevalence in cattle and buffalos in Amazonas State, Brazil. Tissue samples from 151 animals (45 buffalo and 106 cattle from five herds with buffalo only, 22 herds with cattle only, and 12 herds with buffalo and cattle) were obtained from slaughterhouses under State Veterinary Inspection. M. bovis were isolated on Stonebrink medium. The positive cultures were confirmed by polymerase chain reaction (PCR) testing. The apparent herd and animal prevalence rates were 56.4 and 5.40%, respectively. Regarding animal species, the apparent prevalence rates were 3% in cattle and 11.8% in buffalo. Generalized Linear Mixed Models (GLMM) with random effect were used to assess the association with risk factors on the prevalence. Species (buffalo), herds size (>100 animals) and the presence of both species (buffalo and cattle) in the herd were the major risk factors for the infection by Mycobacterium bovis in the region. The findings reveal an urgent need for evidence-based effective intervention to reduce BTB prevalence in cattle and buffalo and prevent its spread to the human population. Studies are needed to understand why buffalo are more likely to be infected by M. bovis than cattle in Amazon. Recommendations for zoning, use of data from the inspection services to generate information regarding BTB focus, adoption of epidemiological tools, and discouragement of practices that promote the mixing of cattle and buffalo, were made.

Vancomycin-resistant Staphylococcus aureus in the United States, 2002-2006.

BACKGROUND: This report compares the clinical characteristics, epidemiologic investigations, infection-control evaluations, and microbiologic findings of all 7 of the cases of vancomycin-resistant Staphylococcus aureus (VRSA) infection in the United States during the period 2002-2006. METHODS: Epidemiologic, clinical, and infection-control information was collected. VRSA isolates underwent confirmatory identification, antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and typing of the resistance genes. To assess VRSA transmission, case patients and their contacts were screened for VRSA carriage. RESULTS: Seven cases were identified from 2002 through 2006; 5 were reported from Michigan, 1 was reported from Pennsylvania, and 1 was reported from New York. All VRSA isolates were vanA positive and had a median vancomycin minimum inhibitory concentration of 512 microg/mL. All case patients had a history of prior methicillin-resistant S. aureus and enterococcal infection or colonization; all had several underlying conditions, including chronic skin ulcers; and most had received vancomycin therapy prior to their VRSA infection. Person-to-person transmission of VRSA was not identified beyond any of the case patients. Infection-control precautions were evaluated and were consistent with established guidelines. CONCLUSIONS: Seven patients with vanA-positive VRSA have been identified in the United States. Prompt detection by microbiology laboratories and adherence to recommended infection control measures for multidrug-resistant organisms appear to have prevented transmission to other patients.

Multistate outbreak of Pseudomonas fluorescens bloodstream infection after exposure to contaminated heparinized saline flush prepared by a compounding pharmacy.

BACKGROUND: Pharmaceutical compounding, the manipulation of ingredients to create a customized medication, is a widespread practice. In January 2005, the Centers for Disease Control and Prevention was notified of 4 cases of Pseudomonas fluorescens bacteremia that were traced to contaminated heparinized saline intravenous flush syringes prepared as a compounded medical product. PATIENTS AND METHODS: We reviewed medical records of symptomatic patients with P. fluorescens-positive cultures of blood specimens or sections of explanted catheters, reviewed the production process of syringes, performed syringe cultures, compared isolates by pulsed-field gel electrophoresis (PFGE), and examined catheters by scanning electron microscopy. RESULTS: We identified 80 patients in 6 states with P. fluorescens-positive cultures during December 2004-March 2006. Sixty-four patients (80%) had received a diagnosis of cancer. Seventy-four (99%) of 75 patients for whom information about catheter type was available had long-term indwelling catheters. Thirty-three (41%) of 80 cases were diagnosed 84-421 days after the patient's last potential exposure to a contaminated flush (delayed-onset cases). Compared with patients with early infection onset, more patients with delayed infection onset had venous ports (100% versus 50%; P <.001). By PFGE, clinical isolates from 50 (98%) of 51 patients were related to isolates cultured from unopened syringes. Scanning electron microscopy of explanted catheters revealed biofilms containing organisms morphologically consistent with P. fluorescens. CONCLUSION: This outbreak underscores important challenges in ensuring the safety of compounded pharmaceuticals and demonstrates the potential for substantially delayed infections after exposures to contaminated infusates. Exposures to compounded products should be considered when investigating outbreaks. Patients exposed to contaminated infusates require careful follow-up, because infections can occur long after exposure.

Human Mycobacterium bovis infection and bovine tuberculosis outbreak, Michigan, 1994-2007.

Mycobacterium bovis is endemic in Michigan's white-tailed deer and has been circulating since 1994. The strain circulating in deer has remained genotypically consistent and was recently detected in 2 humans. We summarize the investigation of these cases and confirm that recreational exposure to deer is a risk for infection in humans.

Epidemiologic attributes of invasive non-typhoidal Salmonella infections in Michigan, 1995--2001.

OBJECTIVES: To determine: (1) the incidence of invasive salmonellosis, (2) the distribution of specific Salmonella serotypes associated with invasive disease, and (3) the role of demographic characteristics in invasive salmonellosis in Michigan. DESIGN: We conducted a cross-sectional study using laboratory-confirmed cases of salmonellosis reported to the Michigan Department of Community Health between 1995 and 2001. METHODS: Average annual incidences (AAIs) for invasive salmonellosis were computed, and Poisson regression analysis was used to model the association between demographic attributes and invasive salmonellosis. RESULTS: Of 6797 cases of salmonellosis, 347 (5.1%) were characterized as invasive having an AAI of 0.5/100000. A covariate-adjusted Poisson model showed children aged <1 year to be at higher risk for invasive salmonellosis compared to adults aged 40-49 years (rate ratio (RR) 8.98, 95% confidence interval (CI) 5.69-14.17). No significant differences were found between males and females (RR 1.02, 95% CI 0.83-1.26), African-Americans and Caucasians (RR 0.95, 95% CI 0.64-1.42), and urban and rural residents (RR 0.98, 95% CI 0.76-1.26). Among the most common serotypes associated with invasive salmonellosis (Heidelberg, Typhimurium, and Enteritidis), Salmonella serotype Heidelberg had the highest blood invasiveness ratio (15.79/100). CONCLUSIONS: Children aged <1 year, especially of minority groups, are at higher risk for invasive Salmonella infections. Invasive salmonellosis may be included in the differential diagnosis of acute bacterial infections in young children with positive stool cultures for Salmonella.

Prevalence of Bovine Leukemia Virus Antibodies in US Dairy Cattle.

OBJECTIVE: To estimate current US herd-level and animal-level prevalence of bovine leukemia virus (BLV) in dairy cows and characterize epidemiologic features. DESIGN: Cross-sectional observational study design and survey. ANIMALS: 4120 dairy cows from 103 commercial dairy herds in 11 states across the US. PROCEDURES: Milk samples were collected from dairy cows through routine commercial sampling and tested for anti-BLV antibodies by antibody capture ELISA. Based on the ELISA results of a sample of an average of 40 cows per herd, within-herd apparent prevalence (AP) was estimated by a directly standardized method and by a lactation-weighted method for each herd. Within-herd AP estimates were summarized to give estimates of US herd-level and animal-level AP. Differences in AP by lactation, region, state, breed, and herd size were examined to characterize basic epidemiologic features of BLV infection. RESULTS: 94.2% of herds had at least one BLV antibody positive cow detected. The average within-herd standardized AP was 46.5%. Lactation-specific AP increased with increasing lactation number, from 29.7% in first lactation cows to 58.9% in 4th and greater lactation cows. Significant differences were not observed based on region, state, breed, or herd size. CONCLUSIONS AND CLINICAL RELEVANCE: These results are consistent with a historical trend of increasing prevalence of BLV among US dairy cattle. Given the findings of other studies on the negative impacts of BLV infection on milk production and cow longevity, these findings are clinically relevant for veterinarians counseling dairy clients on the risks of BLV to their herds.

The role of neighborhood level socioeconomic characteristics in Salmonella infections in Michigan (1997-2007): assessment using geographic information system.

BACKGROUND: The majority of U.S. disease surveillance systems contain incomplete information regarding socioeconomic status (SES) indicators like household or family income and educational attainment in case reports, which reduces the usefulness of surveillance data for these parameters. We investigated the association between select SES attributes at the neighborhood level and Salmonella infections in the three most populated counties in Michigan using a geographic information system. METHODS: We obtained data on income, education, and race from the 2000 U.S. Census, and the aggregate number of laboratory-confirmed cases of salmonellosis (1997-2006) at the block group level from the Michigan Department of Community Health. We used ArcGIS to visualize the distribution, and Poisson regression analysis to study associations between potential predictor variables and Salmonella infections. RESULTS: Based on data from 3,419 block groups, our final multivariate model revealed that block groups with lower educational attainment were less commonly represented among cases than their counterparts with higher education levels (< high school degree vs. > or = college degree: rate ratio (RR) = 0.79, 95% confidence interval (CI):0.63, 0.99; > or = and high school degree, but no college degree vs. > or = college degree: RR = 0.84, 95% CI: 0.76, 0.92). Levels of education also showed a dose-response relation with the outcome variable, i.e., decreasing years of education was associated with a decrease in Salmonella infections incidence at the block group level. CONCLUSION: Education plays a significant role in health-seeking behavior at the population level. It is conceivable that a reporting bias may exist due to a greater detection of Salmonella infections among high education block groups compared to low education block groups resulting from differential access to healthcare. In addition, individuals of higher education block groups who also have greater discretionary income may eat outside the home frequently and be more likely to own pets considered reservoirs of Salmonella, which increase the likelihood of contracting Salmonella infections compared to their counterparts with lower levels of education. Public health authorities should focus on improving the level of disease detection and reporting among communities with lower income and education and further evaluate the role of higher educational attainment in the predisposition for salmonellosis.

Spatial epidemiology of HIV-hepatitis co-infection in the State of Michigan: a cohort study.

BACKGROUND: Acquired immunodeficiency syndrome (AIDS) is a continuing global public health threat affecting millions of individuals. In 2009, 33.3 million people worldwide were living with human immunodeficiency virus (HIV) infection. HIV-infected individuals are at an increased risk of acquiring hepatitis B and hepatitis C viral (HBV, HCV)infections because of shared transmission routes. The purpose of this study was to identify geographical clusters of HIV-(HBV/HCV) co-infection in the State of Michigan. METHODS: Retrospective cohort data on HIV-infected individuals were matched to all hepatitis B and C cases in Michigan during the period of January 1, 2006 through December 31, 2009. A prevalence map of HIV infection was created and spatial clusters of HIV-hepatitis B or C co-infection were detected using GeoDa's bivariate local Moran's I and SaTScan's discrete Poisson model. RESULTS: A bivariate cluster of high prevalence HIV and hepatitis B or C was identified in the Detroit Metropolitan Area and surrounding counties. A Poisson cluster of HIV-hepatitis B or C co-infection was identified, relative risk (RR) = 1.38 (p = 0.029) in the western and northwestern counties of Lower Michigan, controlling for sex, race, and AIDS status. CONCLUSION: This study identified elevated HIV-hepatitis B or C co-infection unexplained by sex, race or AIDS status in counties outside of the Detroit Metropolitan Area where HIV prevalence was highest in Michigan. The findings from this study may be used to target future public health policy and healthcare interventions for HIV-hepatitis co-infection in these areas.

Factors influencing school closure and dismissal decisions: influenza A (H1N1), Michigan 2009.

BACKGROUND: In fall 2009, many US communities experienced school closures during the influenza A H1N1 pandemic (pH1N1) and the state of Michigan reported 567 closures. We conducted an investigation in Michigan to describe pH1N1-related school policies, practices, and identify factors related to school closures. METHODS: We distributed an online survey to all Michigan K-12 school principals. Descriptive statistics and chi-square tests summarize school policies, practices, adherence to government guidelines, and differences between schools that closed and those that remained open during the pandemic. RESULTS: Of 4441 traditional K-12 Michigan schools, 937 (21%) principals responded to our survey representing approximately 374,000 students and 17,700 teachers. The majority (88%) of schools had influenza preparedness plans and followed government school influenza guidelines. Among respondents, 15% (137/937) of schools closed in fall 2009 with high absenteeism as the primary reason for closure. Schools that closed reported significant illness in their school, had <300 students, and had invested substantial resources preparing and responding to influenza. CONCLUSIONS: Adherence to government guidelines for schools appears high in Michigan. Closures occurred in schools that reported significant illness and were likely motivated by excessive absenteeism. Understanding factors related to closures during pH1N1 may inform future pandemic preparedness efforts.

Knowledge, attitudes, and practices of nonpharmaceutical interventions following school dismissals during the 2009 Influenza A H1N1 pandemic in Michigan, United States.

BACKGROUND: Many schools throughout the United States reported an increase in dismissals due to the 2009 influenza A H1N1 pandemic (pH1N1). During the fall months of 2009, more than 567 school dismissals were reported from the state of Michigan. In December 2009, the Michigan Department of Community Health, in collaboration with the United States Centers for Disease Control and Prevention, conducted a survey to describe the knowledge, attitudes, and practices (KAPs) of households with school-aged children and classroom teachers regarding the recommended use of nonpharmaceutical interventions (NPIs) to slow the spread of influenza. METHODS: A random sample of eight elementary schools (kindergarten through 5th grade) was selected from each of the eight public health preparedness regions in the state. Within each selected school, a single classroom was randomly identified from each grade (K-5), and household caregivers of the classroom students and their respective teachers were asked to participate in the survey. RESULTS: In total, 26% (2,188/8,280) of household caregivers and 45% (163/360) of teachers from 48 schools (of the 64 sampled) responded to the survey. Of the 48 participating schools, 27% (13) experienced a school dismissal during the 2009 fall term. Eighty-seven percent (1,806/2,082) of caregivers and 80% (122/152) of teachers thought that the 2009 influenza A H1N1 pandemic was severe, and >90% of both groups indicated that they told their children/students to use NPIs, such as washing hands more often and covering coughs with tissues, to prevent infection with influenza. CONCLUSIONS: Knowledge and instruction on the use of NPIs appeared to be high among household caregivers and teachers responding to the survey. Nevertheless, public health officials should continue to explain the public health rationale for NPIs to reduce pandemic influenza. Ensuring this information is communicated to household caregivers and teachers through trusted sources is essential.

Michigan Clostridium difficile hospital discharges: frequency, mortality, and charges, 2002-2008.

OBJECTIVE: Clostridium difficile (C. difficile) causes an intestinal bacterial infection of increasing importance in Michigan residents and health-care facilities. The specific burden and health-care costs of C. difficile infection (CDI) were previously unknown. We evaluated the frequency, mortality, and health-care charges of CDI from Michigan hospital discharge data. METHODS: The Michigan Department of Community Health purchased discharge data from all Michigan acute care hospitals from the Michigan Health and Hospital Association. We extracted all hospital discharges from 2002 through 2008 containing the International Classification of Diseases, Ninth Revision code for intestinal infection due to C. difficile. Discharges were stratified by principle diagnosis and comorbidity level. Total hospitalization charges were standardized to the 2008 U.S. dollar. RESULTS: From 2002 through 2008, 68,686 hospital discharges with CDI occurred. The annual rate increased from 463.1 to 1096.5 CDI discharges per 100,000 discharges. CDI discharge rates were substantially higher among the elderly, females, and black people. Of all CDI discharges, 5,924 (8.6%) patients died. The mean total health-care charge for the time period was $67,149, and the annual mean increased 35% from 2002 to 2008. Hospital charges varied significantly by race/ethnicity and age. People with Medicaid insurance accrued the highest charges. CONCLUSION: Across Michigan, the CDI burden is growing substantially and affecting vulnerable populations. Surveillance utilizing hospital discharge data can illuminate trends and inform intervention targets. To reduce disease and health-care charges, increased prevention and infection-control efforts should be directed toward high-risk populations, such as the elderly.