Integrated Forecasts Based on Public Health Surveillance and Meteorological Data Predict West Nile Virus in a High-Risk Region of North America.

BACKGROUND: West Nile virus (WNV), a global arbovirus, is the most prevalent mosquito-transmitted infection in the United States. Forecasts of WNV risk during the upcoming transmission season could provide the basis for targeted mosquito control and disease prevention efforts. We developed the Arbovirus Mapping and Prediction (ArboMAP) WNV forecasting system and used it in South Dakota from 2016 to 2019. This study reports a post hoc forecast validation and model comparison. OBJECTIVES: Our objective was to validate historical predictions of WNV cases with independent data that were not used for model calibration. We tested the hypothesis that predictive models based on mosquito surveillance data combined with meteorological variables were more accurate than models based on mosquito or meteorological data alone. METHODS: The ArboMAP system incorporated models that predicted the weekly probability of observing one or more human WNV cases in each county. We compared alternative models with different predictors including a) a baseline model based only on historical WNV cases, b) mosquito models based on seasonal patterns of infection rates, c) environmental models based on lagged meteorological variables, including temperature and vapor pressure deficit, d) combined models with mosquito infection rates and lagged meteorological variables, and e) ensembles of two or more combined models. During the WNV season, models were calibrated using data from previous years and weekly predictions were made using data from the current year. Forecasts were compared with observed cases to calculate the area under the receiver operating characteristic curve (AUC) and other metrics of spatial and temporal prediction error. RESULTS: Mosquito and environmental models outperformed the baseline model that included county-level averages and seasonal trends of WNV cases. Combined models were more accurate than models based only on meteorological or mosquito infection variables. The most accurate model was a simple ensemble mean of the two best combined models. Forecast accuracy increased rapidly from early June through early July and was stable thereafter, with a maximum AUC of 0.85. The model predictions captured the seasonal pattern of WNV as well as year-to-year variation in case numbers and the geographic pattern of cases. DISCUSSION: The predictions reached maximum accuracy early enough in the WNV season to allow public health responses before the peak of human cases in August. This early warning is necessary because other indicators of WNV risk, including early reports of human cases and mosquito abundance, are poor predictors of case numbers later in the season. https://doi.org/10.1289/EHP10287.

Vaccine Breakthrough Cases in South Dakota: Impact of SARS-CoV-2 Variants in a Rural State.

BACKGROUND: Emergence of the SARS-CoV-2 Delta variant raised concern for greater transmissibility and severity of illness compared to the Alpha variant. Our objective was to compare SARS-CoV-2 vaccine breakthrough cases in South Dakota during the time periods where the Alpha and Delta variants of SARS-CoV-2 predominated. METHODS: Data were obtained from the South Dakota Department of Health's electronic disease surveillance system and South Dakota's Health Information Exchange. SARS-CoV-2 cases were matched with the immunization system data to verify vaccination status of vaccine breakthrough cases (VBC). The Alpha variant time-period (ATP) was defined as April 15-May 10, 2021 and the Delta variant time-period (DTP) as July 18-31, 2021. Case rates, demographics, risk factors, symptomology, and outcomes were compared for VBC during these periods. RESULTS: A total of 155 VBC were reported during the ATP and 153 during the DTP. The rate of SARS-CoV-2 VBC was 1.88 times higher for the DTP than the ATP. VBC during the ATP were more likely to present with no symptoms and during the DTP were more likely to present with subjective fever, cough, headache, loss or altered smell/taste, congestion, or postnasal drip. The average hospital length of stay was 6 days for the ATP and 4 days for the DTP. A total of 5 deaths were reported during the ATP compared to 1 death during the DTP. The non-statistically significant relation of the ATP and the DTP for hospital length of stay and number of deaths indicated a similar severity of disease. CONCLUSIONS: In fully vaccinated South Dakotans, the SARS-CoV-2 Delta variant was shown to cause 1.88 times higher breakthrough cases but resulted in similar severity of illness compared to the Alpha variant.

Coronavirus Disease among Workers in Food Processing, Food Manufacturing, and Agriculture Workplaces.

We describe coronavirus disease (COVID-19) among US food manufacturing and agriculture workers and provide updated information on meat and poultry processing workers. Among 742 food and agriculture workplaces in 30 states, 8,978 workers had confirmed COVID-19; 55 workers died. Racial and ethnic minority workers could be disproportionately affected by COVID-19.

COVID-19 Mortality Among American Indian and Alaska Native Persons - 14 States, January-June 2020.

American Indian/Alaska Native (AI/AN) persons experienced disproportionate mortality during the 2009 influenza A(H1N1) pandemic (1,2). Concerns of a similar trend during the coronavirus disease 2019 (COVID-19) pandemic led to the formation of a workgroup* to assess the prevalence of COVID-19 deaths in the AI/AN population. As of December 2, 2020, CDC has reported 2,689 COVID-19-associated deaths among non-Hispanic AI/AN persons in the United States.† A recent analysis found that the cumulative incidence of laboratory-confirmed COVID-19 cases among AI/AN persons was 3.5 times that among White persons (3). Among 14 participating states, the age-adjusted AI/AN COVID-19 mortality rate (55.8 deaths per 100,000; 95% confidence interval [CI] = 52.5-59.3) was 1.8 (95% CI = 1.7-2.0) times that among White persons (30.3 deaths per 100,000; 95% CI = 29.9-30.7). Although COVID-19 mortality rates increased with age among both AI/AN and White persons, the disparity was largest among those aged 20-49 years. Among persons aged 20-29 years, 30-39 years, and 40-49 years, the COVID-19 mortality rates among AI/AN were 10.5, 11.6, and 8.2 times, respectively, those among White persons. Evidence that AI/AN communities might be at increased risk for COVID-19 illness and death demonstrates the importance of documenting and understanding the reasons for these disparities while developing collaborative approaches with federal, state, municipal, and tribal agencies to minimize the impact of COVID-19 on AI/AN communities. Together, public health partners can plan for medical countermeasures and prevention activities for AI/AN communities.

Assessing County-Level Vulnerability for Opioid Overdose and Rapid Spread of Human Immunodeficiency Virus and Hepatitis C Infection in South Dakota.

BACKGROUND: Key indicators of vulnerability for the syndemic of opioid overdose, human immunodeficiency virus (HIV), and hepatitis C virus (HCV) due to injection drug use (IDU) in rural reservation and frontier counties are unknown. We examined county-level vulnerability for this syndemic in South Dakota. METHODS: Informed by prior methodology from the Centers for Disease Control and Prevention, we used acute and chronic HCV infections among persons aged ≤40 years as a proxy measure of IDU. Twenty-nine county-level indicators potentially associated with HCV infection rates were identified. Using these indicators, we examined relationships through bivariate and multivariate analysis and calculated a composite index score to identify the most vulnerable counties (top 20%) to this syndemic. RESULTS: Of the most vulnerable counties, 69% are reservation counties and 62% are rural. The county-level HCV infection rate is 4 times higher in minority counties than nonminority counties, and almost all significant indicators of opioid-related vulnerability in our analysis are structural and potentially modifiable through public health interventions and policies. CONCLUSIONS: Our assessment gives context to the magnitude of this syndemic in rural reservation and frontier counties and should inform the strategic allocation of prevention and intervention services.

COVID-19 Outbreak Among Employees at a Meat Processing Facility - South Dakota, March-April 2020.

On March 24, 2020, the South Dakota Department of Health (SDDOH) was notified of a case of coronavirus disease 2019 (COVID-19) in an employee at a meat processing facility (facility A) and initiated an investigation to isolate the employee and identify and quarantine contacts. On April 2, when 19 cases had been confirmed among facility A employees, enhanced testing for SARS-CoV-2, the virus that causes COVID-19, was implemented, so that any employee with a COVID-19-compatible sign or symptom (e.g., fever, cough, or shortness of breath) could receive a test from a local health care facility. By April 11, 369 COVID-19 cases had been confirmed among facility A employees; on April 12, facility A began a phased closure* and did not reopen during the period of investigation (March 16-April 25, 2020). At the request of SDDOH, a CDC team arrived on April 15 to assist with the investigation. During March 16-April 25, a total of 929 (25.6%) laboratory-confirmed COVID-19 cases were diagnosed among 3,635 facility A employees. At the outbreak's peak, an average of 67 cases per day occurred. An additional 210 (8.7%) cases were identified among 2,403 contacts of employees with diagnosed COVID-19. Overall, 48 COVID-19 patients were hospitalized, including 39 employees and nine contacts. Two employees died; no contacts died. Attack rates were highest among department-groups where employees tended to work in proximity (i.e., <6 feet [2 meters]) to one another on the production line. Cases among employees and their contacts declined to approximately 10 per day within 7 days of facility closure. SARS-CoV-2 can spread rapidly in meat processing facilities because of the close proximity of workstations and prolonged contact between employees (1,2). Facilities can reduce this risk by implementing a robust mitigation program, including engineering and administrative controls, consistent with published guidelines (1).

Update: COVID-19 Among Workers in Meat and Poultry Processing Facilities - United States, April-May 2020.

Meat and poultry processing facilities face distinctive challenges in the control of infectious diseases, including coronavirus disease 2019 (COVID-19) (1). COVID-19 outbreaks among meat and poultry processing facility workers can rapidly affect large numbers of persons. Assessment of COVID-19 cases among workers in 115 meat and poultry processing facilities through April 27, 2020, documented 4,913 cases and 20 deaths reported by 19 states (1). This report provides updated aggregate data from states regarding the number of meat and poultry processing facilities affected by COVID-19, the number and demographic characteristics of affected workers, and the number of COVID-19-associated deaths among workers, as well as descriptions of interventions and prevention efforts at these facilities. Aggregate data on confirmed COVID-19 cases and deaths among workers identified and reported through May 31, 2020, were obtained from 239 affected facilities (those with a laboratory-confirmed COVID-19 case in one or more workers) in 23 states.* COVID-19 was confirmed in 16,233 workers, including 86 COVID-19-related deaths. Among 14 states reporting the total number of workers in affected meat and poultry processing facilities (112,616), COVID-19 was diagnosed in 9.1% of workers. Among 9,919 (61%) cases in 21 states with reported race/ethnicity, 87% occurred among racial and ethnic minority workers. Commonly reported interventions and prevention efforts at facilities included implementing worker temperature or symptom screening and COVID-19 education, mandating face coverings, adding hand hygiene stations, and adding physical barriers between workers. Targeted workplace interventions and prevention efforts that are appropriately tailored to the groups most affected by COVID-19 are critical to reducing both COVID-19-associated occupational risk and health disparities among vulnerable populations. Implementation of these interventions and prevention efforts† across meat and poultry processing facilities nationally could help protect workers in this critical infrastructure industry.

Multistate Mumps Outbreak Originating from Asymptomatic Transmission at a Nebraska Wedding - Six States, August-October 2019.

In August 2019, 30 attendees at a Nebraska wedding developed mumps after being exposed to one asymptomatic index patient who was fully vaccinated according to Advisory Committee on Immunization Practices (ACIP) recommendations (1), resulting in a multistate outbreak. A public health investigation and response revealed epidemiologic links that extended from the index patient through secondary, tertiary, and quaternary patients and culminated in a measles-mumps-rubella (MMR) booster vaccination campaign in the local community where approximately half of the patients resided.

COVID-19 in Correctional and Detention Facilities - United States, February-April 2020.

An estimated 2.1 million U.S. adults are housed within approximately 5,000 correctional and detention facilities† on any given day (1). Many facilities face significant challenges in controlling the spread of highly infectious pathogens such as SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). Such challenges include crowded dormitories, shared lavatories, limited medical and isolation resources, daily entry and exit of staff members and visitors, continual introduction of newly incarcerated or detained persons, and transport of incarcerated or detained persons in multiperson vehicles for court-related, medical, or security reasons (2,3). During April 22-28, 2020, aggregate data on COVID-19 cases were reported to CDC by 37 of 54 state and territorial health department jurisdictions. Thirty-two (86%) jurisdictions reported at least one laboratory-confirmed case from a total of 420 correctional and detention facilities. Among these facilities, COVID-19 was diagnosed in 4,893 incarcerated or detained persons and 2,778 facility staff members, resulting in 88 deaths in incarcerated or detained persons and 15 deaths among staff members. Prompt identification of COVID-19 cases and consistent application of prevention measures, such as symptom screening and quarantine, are critical to protecting incarcerated and detained persons and staff members.

COVID-19 Among Workers in Meat and Poultry Processing Facilities - 19 States, April 2020.

Congregate work and residential locations are at increased risk for infectious disease transmission including respiratory illness outbreaks. SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is primarily spread person to person through respiratory droplets. Nationwide, the meat and poultry processing industry, an essential component of the U.S. food infrastructure, employs approximately 500,000 persons, many of whom work in proximity to other workers (1). Because of reports of initial cases of COVID-19, in some meat processing facilities, states were asked to provide aggregated data concerning the number of meat and poultry processing facilities affected by COVID-19 and the number of workers with COVID-19 in these facilities, including COVID-19-related deaths. Qualitative data gathered by CDC during on-site and remote assessments were analyzed and summarized. During April 9-27, aggregate data on COVID-19 cases among 115 meat or poultry processing facilities in 19 states were reported to CDC. Among these facilities, COVID-19 was diagnosed in 4,913 (approximately 3%) workers, and 20 COVID-19-related deaths were reported. Facility barriers to effective prevention and control of COVID-19 included difficulty distancing workers at least 6 feet (2 meters) from one another (2) and in implementing COVID-19-specific disinfection guidelines.* Among workers, socioeconomic challenges might contribute to working while feeling ill, particularly if there are management practices such as bonuses that incentivize attendance. Methods to decrease transmission within the facility include worker symptom screening programs, policies to discourage working while experiencing symptoms compatible with COVID-19, and social distancing by workers. Source control measures (e.g., the use of cloth face covers) as well as increased disinfection of high-touch surfaces are also important means of preventing SARS-CoV-2 exposure. Mitigation efforts to reduce transmission in the community should also be considered. Many of these measures might also reduce asymptomatic and presymptomatic transmission (3). Implementation of these public health strategies will help protect workers from COVID-19 in this industry and assist in preserving the critical meat and poultry production infrastructure (4).

Public Health Response to an Avian Influenza A(H7N8) Virus Outbreak in Commercial Turkey Flocks - Indiana, 2016.

In January 2016, highly pathogenic avian influenza (HPAI) A(H7N8) virus and low pathogenicity avian influenza (LPAI) A(H7N8) virus were detected in commercial turkey flocks in Dubois County, Indiana. The Indiana State Department of Health (ISDH) and the Dubois County Health Department (DCHD) coordinated the public health response to this outbreak, which was the first detection of HPAI A(H7N8) in any species (1). This response was the first to fully implement unpublished public health monitoring procedures for HPAI responders that were developed by the U.S. Department of Agriculture (USDA) and CDC in 2015 (Sonja Olsen, CDC, personal communication, October 2017). No cases of zoonotic avian influenza infection in humans were detected during the outbreak.

Water Quality Survey of Splash Pads After A Waterborne Salmonellosis Outbreak--Tennessee, 2014.

Waterborne outbreaks of salmonellosis are uncommon. The Tennessee Department of Health investigated a salmonellosis outbreak of 10 cases with the only common risk factor being exposure to a single splash pad. Risks included water splashed in the face at the splash pad and no free residual chlorine in the water system. We surveyed water quality and patron behaviors at splash pads statewide. Of the 29 splash pads participating in the water quality survey, 24 (83%) used a recirculating water system. Of the 24, 5 (21%) water samples were tested by polymerase chain reaction and found to be positive for E. coli, Giardia, norovirus, or Salmonella. Among 95 patrons observed, we identified common high-risk behaviors of sitting on the fountain or spray head and putting mouth to water. Water venue regulations and improved education of patrons are important to aid prevention efforts.

Enhancing Lyme Disease Surveillance by Using Administrative Claims Data, Tennessee, USA.

Lyme disease is underreported in the United States. We used insurance administrative claims data to determine the value of such data in enhancing case ascertainment in Tennessee during January 2011-June 2013. Although we identified ≈20% more cases of Lyme disease (5/year), the method was resource intensive and not sustainable in this low-incidence state.

Influenza vaccination of Michigan children by provider type, 2010-2011.

BACKGROUND: Influenza vaccination for all children aged 6 months to 18 years has been recommended since 2008 to prevent flu-related morbidity and mortality. However, 2010-2011 influenza vaccine coverage estimates show under-vaccination in children of all ages. We examined predictors of influenza vaccination in Michigan during the 2010-2011 influenza season. PURPOSE: To determine whether immunization provider type was associated with a child's influenza vaccination in Michigan and assess whether county-level factors were confounders of the association. METHODS: Influenza vaccinations reported to the Michigan Care Improvement Registry from the 2010-2011 influenza season were analyzed in 2012 to estimate ORs for the association between immunization provider type and influenza vaccination. RESULTS: Among 2,373,826 Michigan children aged 6 months through 17 years, 17% were vaccinated against influenza and lower vaccination rates were observed for public compared to private providers (13% vs 18%). In the unadjusted model, public providers had lower odds of vaccinating children compared to private providers (OR=0.60, 95% CI=0.60, 0.61). County-level factors, including percentage of families living below the poverty line, median household income, and percentage black race, were not shown to confound the association. In the adjusted models, public providers had lower odds of vaccinating children compared to private providers (OR=0.87, 95% CI=0.86, 0.88). CONCLUSIONS: Although a child's likelihood of influenza vaccination in Michigan varies by provider type, more effective strategies to improve influenza vaccination rates for all Michigan children are needed.

Challenges to recruitment and retention of the state health department epidemiology workforce.

BACKGROUND: With nearly one quarter of the combined governmental public health workforce eligible for retirement within the next few years, recruitment and retention of workers is a growing concern. Epidemiology has been identified as a potential workforce shortage area in state health departments. PURPOSE: Understanding strategies for recruiting and retaining epidemiologists may help health departments stabilize their epidemiology workforce. The Council of State and Territorial Epidemiologists conducted a survey, the Epidemiology Capacity Assessment (ECA), of state health departments to identify recruitment and retention factors. METHODS: The ECA was distributed to 50 states, the District of Columbia (DC), and four U.S. territories in 2009. The 50 states and DC are included in this analysis. The State Epidemiologist completed the organizational-level assessment; health department epidemiologists completed an individual-level assessment. Data were analyzed in 2010. RESULTS: All states responded to the ECA, as did 1544 epidemiologists. Seventeen percent of epidemiologists reported intent to retire or change careers in the next 5 years. Ninety percent of states and DC identified state and local government websites, schools of public health, and professional organizations as the most useful recruitment tools. Top recruitment barriers included salary scale, hiring freezes, and ability to offer competitive pay; lack of promotion opportunities and merit raise restrictions were main retention barriers. CONCLUSIONS: Although the proportion of state health department epidemiologists intending to retire or change careers during the next 5 years is lower than the estimate for the total state public health workforce, important recruitment and retention barriers for the employees exist.