Health system resource use among populations with complex social and behavioral needs in an urban, safety-net health system.

BACKGROUND: Costs incurred by health systems when caring for populations with social or behavioral complexity are poorly understood. We compared the frequency and costs of unreimbursed care among individuals with complexity factors (homelessness, a history of county jail incarceration, and/or substance use disorder or mental illness [SUD/MI]). METHODS: We conducted a cross-sectional analysis using electronic health record data for adults aged 18 and older between January 1, 2016 and December 31, 2017 from a Midwestern safety-net health system. Zero-inflated negative binomial regression models were used to assess risk-adjusted associations between complexity factors and care coordination encounters, missed appointments, and excess inpatient days. RESULTS: Our sample included 154,719 unique patients; 6.8% were identified as homeless, 7.8% had a history of county jail incarceration, and 20.6% had SUD/MI. Individuals with complexity factors were more likely to be African-American, Native American, or covered by Medicaid. In adjusted models, homelessness and SUD/MI were significantly associated with care coordination encounters (RR 1.8 [95% CI,1.7-2.0]; RR 1.9 [95% CI,1.8-2.0]), missed appointments (RR 1.5 [95% CI,1.4-1.6]; RR 1.7 [95% CI,1.7-1.8]), and excess inpatient days (RR 1.5 [95% CI,1.3-1.8]; RR 2.8 [95% CI,2.5-3.1]). County jail incarceration was associated with a significant increase in missed appointments. In 2017, SUD/MI accounted for 81.8% ($7,773,000/$9,502,000) of excess costs among those with social or behavioral complexity. CONCLUSIONS: Social and behavioral complexity are independently associated with high levels of unreimbursed health system resource use. IMPLICATIONS: Future payment models should account for the health system resources required to care for populations with complex social and behavioral needs. LEVEL OF EVIDENCE: IV.

Water quality, availability, and acute gastroenteritis on the Navajo Nation - a pilot case-control study.

The Navajo Nation includes approximately 250,000 American Indians living in a remote high desert environment with limited access to public water systems. We conducted a pilot case-control study to assess associations between acute gastroenteritis (AGE) and water availability, use patterns, and quality. Case patients with AGE and non-AGE controls who presented for care to two Indian Health Service hospitals were recruited. Data on demographics and water use practices were collected using a standard questionnaire. Household drinking water was tested for presence of pathogens, coliforms, and residual chlorine. Sixty-one subjects (32 cases and 29 controls) participated in the study. Cases and controls were not significantly different with respect to water sources, quality, or patterns of use. Twenty-one percent (n = 12) of study participants resided in dwellings not connected to a community water system. Eleven percent (n = 7) of subjects reported drinking hauled water from unregulated sources. Coliform bacteria were present in 44% (n = 27) of household water samples, and 68% (n = 40) of samples contained residual chlorine concentrations of <0.2 mg/L. This study highlights issues with water availability, quality, and use patterns within the Navajo Nation, including sub-optimal access to community water systems, and use of water hauled from unregulated sources.

Cholera Epidemic - Lusaka, Zambia, October 2017-May 2018.

On October 6, 2017, an outbreak of cholera was declared in Zambia after laboratory confirmation of Vibrio cholerae O1, biotype El Tor, serotype Ogawa, from stool specimens from two patients with acute watery diarrhea. The two patients had gone to a clinic in Lusaka, the capital city, on October 4. Cholera cases increased rapidly, from several hundred cases in early December 2017 to approximately 2,000 by early January 2018 (Figure). In collaboration with partners, the Zambia Ministry of Health (MoH) launched a multifaceted public health response that included increased chlorination of the Lusaka municipal water supply, provision of emergency water supplies, water quality monitoring and testing, enhanced surveillance, epidemiologic investigations, a cholera vaccination campaign, aggressive case management and health care worker training, and laboratory testing of clinical samples. In late December 2017, a number of water-related preventive actions were initiated, including increasing chlorine levels throughout the city's water distribution system and placing emergency tanks of chlorinated water in the most affected neighborhoods; cholera cases declined sharply in January 2018. During January 10-February 14, 2018, approximately 2 million doses of oral cholera vaccine were administered to Lusaka residents aged ≥1 year. However, in mid-March, heavy flooding and widespread water shortages occurred, leading to a resurgence of cholera. As of May 12, 2018, the outbreak had affected seven of the 10 provinces in Zambia, with 5,905 suspected cases and a case fatality rate (CFR) of 1.9%. Among the suspected cases, 5,414 (91.7%), including 98 deaths (CFR = 1.8%), occurred in Lusaka residents.

Notes from the Field: Four Multistate Outbreaks of Human Salmonella Infections Linked to Small Turtle Exposure - United States, 2015.

In August 2015, the Food and Drug Administration (FDA) notified CDC of a consumer complaint involving Salmonella Sandiego infection in a child (the index patient), who had acquired a small turtle (shell length <4 inches [<10 cm]) at an Alabama flea market. The subsequent investigation, which included examining data from PulseNet, the national molecular subtyping network for foodborne disease surveillance, identified four multistate Salmonella outbreaks: two involving Salmonella Sandiego and two involving Salmonella Poona. These serotypes have been linked to small turtles in previous outbreaks (1,2). Although selling small turtles as pets in the United States has been banned since 1975 (3), illegal sales still occur at discount stores and flea markets and by street vendors. CDC investigated to determine the extent of the outbreaks and prevent additional infections.

Multistate outbreak of human Salmonella Typhimurium infections linked to live poultry from agricultural feed stores and mail-order hatcheries, United States 2013.

Live poultry-associated salmonellosis is an emerging public health issue in the United States. Public and animal health officials collaborated to investigate one of the largest (356 cases, 39 states) of these outbreaks reported to date. A case was defined as illness in a person infected with the outbreak strain of Salmonella Typhimurium with illness onset between 1 March and 22 October 2013. The median patient age was seven years (range: < 1-87 years); 58% of ill persons were children ≤ 10 years, 51% were female, 25% were hospitalized; 189 (76%) of 250 patients reported live poultry exposure in the week before illness; and 149 (95%) of 157 reported purchasing live poultry from agricultural feed stores. Traceback investigations identified 18 live poultry sources, including 16 mail-order hatcheries. Environmental sampling was conducted at two mail-order hatcheries. One (2.5%) of 40 duplicate samples collected at one hatchery yielded the outbreak strain. Live poultry are an important source of human salmonellosis, particularly among children, highlighting the need for educational campaigns and comprehensive interventions at the mail-order hatchery and agricultural feed store levels. Prevention and control efforts depend on a One Health approach, involving cooperation between public and animal health officials, industry, health professionals, and consumers.

Increased Likelihood of Missed Appointments ("No Shows") for Racial/Ethnic Minorities in a Safety Net Health System.

Missed appointments have been linked to adverse outcomes known to affect racial/ethnic minorities. However, the association of missed appointments with race/ethnicity has not been determined. We sought to determine the relationships between race/ethnicity and missed appointments by performing a cross-sectional study of 161 350 patients in a safety net health system. Several race/ethnicity categories were significantly associated with missed appointment rates, including Hispanic/Latino patients, American Indian/Alaskan Native patients, and Black/African American patients, as compared with White non-Hispanic patients. Other significant predictors included Mexico as country of origin, medical complexity, and major mental illness. We recommend additional research to determine which interventions best reduce missed appointments for minority populations in order to improve the care of vulnerable patients.

Outbreaks of Salmonellosis From Small Turtles.

OBJECTIVE: Turtle-associated salmonellosis (TAS), especially in children, is a reemerging public health issue. In 1975, small pet turtles (shell length <4 inches) sales were banned by federal law; reductions in pediatric TAS followed. Since 2006, the number of multistate TAS outbreaks has increased. We describe 8 multistate outbreaks with illness-onset dates occurring in 2011-2013. METHODS: We conducted epidemiologic, environmental, and traceback investigations. Cases were defined as infection with ≥ 1 of 10 molecular subtypes of Salmonella Sandiego, Pomona, Poona, Typhimurium, and I 4,[5],12:i:-. Water samples from turtle habitats linked to human illnesses were cultured for Salmonella. RESULTS: We identified 8 outbreaks totaling 473 cases from 41 states, Washington DC, and Puerto Rico with illness onsets during May 2011-September 2013. The median patient age was 4 years (range: 1 month-94 years); 45% percent were Hispanic; and 28% were hospitalized. In the week preceding illness, 68% (187 of 273) of case-patients reported turtle exposure; among these, 88% (124 of 141) described small turtles. Outbreak strains were isolated from turtle habitats linked to human illnesses in seven outbreaks. Traceback investigations identified 2 Louisiana turtle farms as the source of small turtles linked to 1 outbreak; 1 outbreak strain was isolated from turtle pond water from 1 turtle farm. CONCLUSIONS: Eight multistate outbreaks associated with small turtles were investigated during 2011-2013. Children <5 years and Hispanics were disproportionately affected. Prevention efforts should focus on patient education targeting families with young children and Hispanics and enactment of state and local regulations to complement federal sales restrictions.

Insights into the environmental reservoir of pathogenic Vibrio parahaemolyticus using comparative genomics.

Vibrio parahaemolyticus is an aquatic halophilic bacterium that occupies estuarine and coastal marine environments, and is a leading cause of seafood-borne food poisoning cases. To investigate the environmental reservoir and potential gene flow that occurs among V. parahaemolyticus isolates, the virulence-associated gene content and genome diversity of a collection of 133 V. parahaemolyticus isolates were analyzed. Phylogenetic analysis of housekeeping genes, and pulsed-field gel electrophoresis, demonstrated that there is genetic similarity among V. parahaemolyticus clinical and environmental isolates. Whole-genome sequencing and comparative analysis of six representative V. parahaemolyticus isolates was used to identify genes that are unique to the clinical and environmental isolates examined. Comparative genomics demonstrated an O3:K6 environmental isolate, AF91, which was cultured from sediment collected in Florida in 2006, has significant genomic similarity to the post-1995 O3:K6 isolates. However, AF91 lacks the majority of the virulence-associated genes and genomic islands associated with these highly virulent post-1995 O3:K6 genomes. These findings demonstrate that although they do not contain most of the known virulence-associated regions, some V. parahaemolyticus environmental isolates exhibit significant genetic similarity to clinical isolates. This highlights the dynamic nature of the V. parahaemolyticus genome allowing them to transition between aquatic and host-pathogen states.

Hennepin Health: a safety-net accountable care organization for the expanded Medicaid population.

Health care payment and delivery models that challenge providers to be accountable for outcomes have fueled interest in community-level partnerships that address the behavioral, social, and economic determinants of health. We describe how Hennepin Health--a county-based safety-net accountable care organization in Minnesota--has forged such a partnership to redesign the health care workforce and improve the coordination of the physical, behavioral, social, and economic dimensions of care for an expanded community of Medicaid beneficiaries. Early outcomes suggest that the program has had an impact in shifting care from hospitals to outpatient settings. For example, emergency department visits decreased 9.1 percent between 2012 and 2013, while outpatient visits increased 3.3 percent. An increasing percentage of patients have received diabetes, vascular, and asthma care at optimal levels. At the same time, Hennepin Health has realized savings and reinvested them in future improvements. Hennepin Health offers lessons for counties, states, and public hospitals grappling with the problem of how to make the best use of public funds in serving expanded Medicaid populations and other communities with high needs.

Increase in Vibrio parahaemolyticus infections associated with consumption of Atlantic Coast shellfish--2013.

Vibrio parahaemolyticus (Vp) is found naturally in coastal saltwater. In the United States, Vp causes an estimated 35,000 domestically acquired foodborne infections annually, of which most are attributable to consumption of raw or undercooked shellfish. Illness typically consists of mild to moderate gastroenteritis, although severe infection can occur. Demographic, clinical, and exposure information (including traceback information on implicated seafood) for all laboratory-confirmed illnesses are reported by state health departments to CDC through the Cholera and Other Vibrio Surveillance system. Vp isolates are distinguished by serotyping (>90 serotypes have been described) and by pulsed-field gel electrophoresis (PFGE).

Shifts in geographic distribution and antimicrobial resistance during a prolonged typhoid fever outbreak--Bundibugyo and Kasese Districts, Uganda, 2009-2011.

BACKGROUND: Salmonella enterica serovar Typhi is transmitted by fecally contaminated food and water and causes approximately 22 million typhoid fever infections worldwide each year. Most cases occur in developing countries, where approximately 4% of patients develop intestinal perforation (IP). In Kasese District, Uganda, a typhoid fever outbreak notable for a high IP rate began in 2008. We report that this outbreak continued through 2011, when it spread to the neighboring district of Bundibugyo. METHODOLOGY/PRINCIPAL FINDINGS: A suspected typhoid fever case was defined as IP or symptoms of fever, abdominal pain, and ≥1 of the following: gastrointestinal disruptions, body weakness, joint pain, headache, clinically suspected IP, or non-responsiveness to antimalarial medications. Cases were identified retrospectively via medical record reviews and prospectively through laboratory-enhanced case finding. Among Kasese residents, 709 cases were identified from August 1, 2009-December 31, 2011; of these, 149 were identified during the prospective period beginning November 1, 2011. Among Bundibugyo residents, 333 cases were identified from January 1-December 31, 2011, including 128 cases identified during the prospective period beginning October 28, 2011. IP was reported for 507 (82%) and 59 (20%) of Kasese and Bundibugyo cases, respectively. Blood and stool cultures performed for 154 patients during the prospective period yielded isolates from 24 (16%) patients. Three pulsed-field gel electrophoresis pattern combinations, including one observed in a Kasese isolate in 2009, were shared among Kasese and Bundibugyo isolates. Antimicrobial susceptibility was assessed for 18 isolates; among these 15 (83%) were multidrug-resistant (MDR), compared to 5% of 2009 isolates. CONCLUSIONS/SIGNIFICANCE: Molecular and epidemiological evidence suggest that during a prolonged outbreak, typhoid spread from Kasese to Bundibugyo. MDR strains became prevalent. Lasting interventions, such as typhoid vaccination and improvements in drinking water infrastructure, should be considered to minimize the risk of prolonged outbreaks in the future.

US outbreak of human Salmonella infections associated with aquatic frogs, 2008-2011.

OBJECTIVE: Although amphibians are known Salmonella carriers, no such outbreaks have been reported. We investigated a nationwide outbreak of human Salmonella Typhimurium infections occurring predominantly among children from 2008 to 2011. METHODS: We conducted a matched case-control study. Cases were defined as persons with Salmonella Typhimurium infection yielding an isolate indistinguishable from the outbreak strain. Controls were persons with recent infection with Salmonella strains other than the outbreak strain and matched to cases by age and geography. Environmental samples were obtained from patients' homes; traceback investigations were conducted. RESULTS: We identified 376 cases from 44 states from January 1, 2008, to December 31, 2011; 29% (56/193) of patients were hospitalized and none died. Median patient age was 5 years (range <1-86 years); 69% were children <10 years old (253/367). Among 114 patients interviewed, 69 (61%) reported frog exposure. Of patients who knew frog type, 79% (44/56) reported African dwarf frogs (ADF), a type of aquatic frog. Among 18 cases and 29 controls, illness was significantly associated with frog exposure (67% cases versus 3% controls, matched odds ratio 12.4, 95% confidence interval 1.9-infinity). Environmental samples from aquariums containing ADFs in 8 patients' homes, 2 ADF distributors, and a day care center yielded isolates indistinguishable from the outbreak strain. Traceback investigations of ADFs from patient purchases converged to a common ADF breeding facility. Environmental samples from the breeding facility yielded the outbreak strain. CONCLUSIONS: ADFs were the source of this nationwide pediatric predominant outbreak. Pediatricians should routinely inquire about pet ownership and advise families about illness risks associated with animals.

Biochemical, serological, and virulence characterization of clinical and oyster Vibrio parahaemolyticus isolates.

In this study, 77 clinical and 67 oyster Vibrio parahaemolyticus isolates from North America were examined for biochemical profiles, serotype, and the presence of potential virulence factors (tdh, trh, and type III secretion system [T3SS] genes). All isolates were positive for oxidase, indole, and glucose fermentation, consistent with previous reports. The isolates represented 35 different serotypes, 9 of which were shared by clinical and oyster isolates. Serotypes associated with pandemic strains (O1:KUT, O1:K25, O3:K6, and O4:K68) were observed for clinical isolates, and 7 (9%) oyster isolates belonged to serotype O1:KUT. Of the clinical isolates, 27% were negative for tdh and trh, while 45% contained both genes. Oyster isolates were preferentially selected for the presence of tdh and/or trh; 34% contained both genes, 42% had trh but not tdh, and 3% had tdh but not trh. All but 1 isolate (143/144) had at least three of the four T3SS1 genes examined. The isolates lacking both tdh and trh contained no T3SS2α or T3SS2ß genes. All clinical isolates positive for tdh and negative for trh possessed all T3SS2α genes, and all isolates negative for tdh and positive for trh possessed all T3SS2ß genes. The two oyster isolates containing tdh but not trh possessed all but the vopB2 gene of T3SS2α, as reported previously. In contrast to the findings of previous studies, all strains examined that were positive for both tdh and trh also carried T3SS2ß genes. This report identifies the serotype as the most distinguishing feature between clinical and oyster isolates. Our findings raise concerns about the reliability of the tdh, trh, and T3SS genes as virulence markers and highlight the need for more-detailed pathogenicity investigations of V. parahaemolyticus.

Characterization of toxigenic Vibrio cholerae from Haiti, 2010-2011.

In October 2010, the US Centers for Disease Control and Prevention received reports of cases of severe watery diarrhea in Haiti. The cause was confirmed to be toxigenic Vibrio cholerae, serogroup O1, serotype Ogawa, biotype El Tor. We characterized 122 isolates from Haiti and compared them with isolates from other countries. Antimicrobial drug susceptibility was tested by disk diffusion and broth microdilution. Analyses included identification of rstR and VC2346 genes, sequencing of ctxAB and tcpA genes, and pulsed-field gel electrophoresis with SfiI and NotI enzymes. All isolates were susceptible to doxycycline and azithromycin. One pulsed-field gel electrophoresis pattern predominated, and ctxB sequence of all isolates matched the B-7 allele. We identified the tcpETCIRS allele, which is also present in Bangladesh strain CIRS 101. These data show that the isolates from Haiti are clonally and genetically similar to isolates originating in Africa and southern Asia and that ctxB-7 and tcpET(CIRS) alleles are undergoing global dissemination.

Toxigenic Vibrio cholerae O1 in water and seafood, Haiti.

During the 2010 cholera outbreak in Haiti, water and seafood samples were collected to detect Vibrio cholerae. The outbreak strain of toxigenic V. cholerae O1 serotype Ogawa was isolated from freshwater and seafood samples. The cholera toxin gene was detected in harbor water samples.

Retail clinic versus office setting: do patients choose appropriate providers?

OBJECTIVE: To assess whether health plan members who used retail clinics chose that setting for minor conditions and continued to see other providers for more complex conditions. STUDY DESIGN: Retrospective analysis of claims data in a commercially insured population. METHODS: Health plan enrollment data were used to identify and describe the analysis population. Episode Treatment Groups were used to identify members with chronic conditions and to analyze reasons for retail clinic use, complexity of retail clinic visits, and care for chronic conditions in non-retail clinic settings. Logistic regression was used to study predictors of retail clinic use. RESULTS: Retail clinic users differed significantly from nonusers. The most significant predictors of retail clinic use were age, sex, and proximity to a retail clinic. Episodes of care treated in the retail clinic appeared to be less complex than similar episodes treated in other settings. Chronically ill members who used the retail clinic saw another provider for their chronic condition at rates similar to or higher than those of members who did not use the retail clinic. CONCLUSIONS: Individuals may be able to identify when conditions are minor enough to be treated in a retail clinic and serious enough to be treated by a traditional provider.

Re-evaluation, optimization, and multilaboratory validation of the PulseNet-standardized pulsed-field gel electrophoresis protocol for Listeria monocytogenes.

The PulseNet Methods Development and Validation Laboratory began a re-evaluation of the standardized pulsed-field gel electrophoresis (PFGE) protocols with the goal of optimizing their overall performance and robustness. Herein, we describe a stepwise evaluation of the PulseNet-standardized PFGE protocol for Listeria monocytogenes that led to the modification of several steps which significantly improved the overall appearance and reproducibility of the resulting PFGE data. These improvements included the following: (1) reducing the cell suspension concentration, (2) increasing lysozyme incubation temperature from 37 degrees C to 56 degrees C, and (3) decreasing the number of units of restriction enzymes AscI and ApaI. These changes were incorporated into a proposed protocol that was evaluated by 16 PulseNet participating laboratories, including 2 international participants. Results from the validation study indicated that the updated L. monocytogenes protocol is more robust than the original PulseNet-standardized protocol established in 1998 and this resulted in the official adoption of the new protocol into the PulseNet system in the spring of 2008. The modifications not only represent an improvement to the protocol but also describe procedural improvements that could be potentially applied to the PFGE analysis of other Gram-positive organisms.

Plan designs that encourage the use of generic drugs over brand-name drugs: an analysis of a free generic benefit.

OBJECTIVE: To evaluate the effect on adherence and medical care expenditures of a pharmacy benefit change that included free generic drugs and higher copayments for brand-name drugs. STUDY DESIGN: Quasi-experimental pre-post study of patients with ischemic heart disease (1286 control and 555 intervention) and patients with diabetes mellitus (4089 control and 1846 intervention). METHODS: Medical and pharmacy claims data were analyzed for continuously enrolled members from January 1, 2005, through December 31, 2008. A generalized linear model was used to predict costs as adherence changed. RESULTS: The rate of switching from brand-name drugs to generic drugs in the intervention group was not statistically different from that in the control group. The net change in adherence was higher only for the intervention group patients taking statins who switched to generic drugs, a 6.2% increase compared with an 8.5% decrease in the control group. The estimate of medical cost savings attributable to this benefit change was significant for only the metformin class of diabetes drugs. Improved adherence independent of this benefit change was estimated to reduce all-cause medical costs for patients taking sulfonylureas, metformin, and thiazolidinediones. CONCLUSIONS: Altering copayments for pharmaceuticals may affect the rate of conversion to generic drugs but is unlikely in and of itself to result in complete conversion. However, increasing adherence can result in net savings for specific diabetic drug classes, as savings from all-cause medical costs offset the increase in pharmacy costs.

Improving the imputation of race: evaluating the benefits of stratifying by age.

Health plans and other health care institutions may use indirect methods such as geocoding and surname analysis to estimate race, ethnicity, and socioeconomic status in an effort to measure disparities in care or target specific demographics. This study investigated whether stratifying by age improved imputations of race and ethnicity made through geocoding. Self-reported race and ethnicity from Medicaid enrollment records and from a health risk assessment administered by a large employer were used to validate imputation results from both an age-stratified model and a standard model. Sensitivity, specificity, and positive predictive value were calculated. Both approaches successfully imputed race and ethnicity for whites, blacks, Asians, and Hispanics. The age-stratified approach identified more blacks than did the unstratified approach, and correctly identified more blacks and whites. The two approaches worked equally well for identifying Asians and Hispanics. Age stratification may improve the accuracy of imputation methods, and help health care organizations to better understand the demographics of the people they serve.

Rapid identification of Vibrio parahaemolyticus by whole-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry.

Vibrio parahaemolyticus is a pathogenic marine bacterium that is the main causative agent of bacterial seafood-borne gastroenteritis in the United States. An increase in the frequency of V. parahaemolyticus-related infections during the last decade has been attributed to the emergence of an O3:K6 pandemic clone in 1995. The diversity of the O3:K6 pandemic clone and its serovariants has been examined using multiple molecular techniques including multilocus sequence analysis, pulsed-field gel electrophoresis, and group-specific PCR analysis. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has become a powerful tool for rapidly distinguishing between related bacterial species. In the current study, we demonstrate the development of a whole-cell MALDI-TOF MS method for the distinction of V. parahaemolyticus from other Vibrio spp. We identified 30 peaks that were present only in the spectra of the V. parahaemolyticus strains examined in this study that may be developed as MALDI-TOF MS biomarkers for identification of V. parahaemolyticus. We detected variation in the MALDI-TOF spectra of V. parahaemolyticus strains isolated from different geographical locations and at different times. The MALDI-TOF MS spectra of the V. parahaemolyticus strains examined were distinct from those of the other Vibrio species examined including the closely related V. alginolyticus, V. harveyi, and V. campbellii. The results of this study demonstrate the first use of whole-cell MALDI-TOF MS analysis for the rapid identification of V. parahaemolyticus.