Estimating hepatitis C prevalence in the United States, 2017-2020.

BACKGROUND AIMS: The National Health and Nutrition Examination Survey (NHANES) underestimates the true prevalence of hepatitis C virus (HCV) infection. By accounting for populations inadequately represented in NHANES, we created two models to estimate the national hepatitis C prevalence among US adults during 2017-2020. APPROACH RESULTS: The first approach (NHANES+) replicated previous methodology by supplementing hepatitis C prevalence estimates among the US noninstitutionalized civilian population with a literature review and meta-analysis of hepatitis C prevalence among populations not included in the NHANES sampling frame. In the second approach (persons who inject drugs [PWID] adjustment), we developed a model to account for underrepresentation of PWID in NHANES by incorporating the estimated number of adult PWID in the United States and applying PWID-specific hepatitis C prevalence estimates. Using the NHANES+ model, we estimated HCV RNA prevalence of 1.0% (95% confidence interval [CI]: 0.5%-1.4%) among US adults in 2017-2020, corresponding to 2,463,700 (95% CI: 1,321,700-3,629,400) current HCV infections. Using the PWID adjustment model, we estimated HCV RNA prevalence of 1.6% (95% CI: 0.9%-2.2%), corresponding to 4,043,200 (95% CI: 2,401,800-5,607,100) current HCV infections. CONCLUSIONS: Despite years of an effective cure, estimated prevalence of hepatitis C in 2017-2020 remains unchanged from 2013-2016 when using comparable methodology. When accounting for increased injection drug use, estimated prevalence of hepatitis C is substantially higher than previously reported. National action is urgently needed to expand testing, increase access to treatment, and improve surveillance, especially among medically underserved populations, to support hepatitis C elimination goals.

Estimated Prevalence and Awareness of Hepatitis C Virus Infection Among US Adults: National Health and Nutrition Examination Survey, January 2017-March 2020.

During January 2017-March 2020, approximately 2.2 million noninstitutionalized civilian US adults had hepatitis C; one-third were unaware of their infection. Prevalence was substantially higher among persons who were uninsured or experiencing poverty. Unrestricted access to testing and curative treatment is needed to reduce disparities and achieve 2030 elimination goals.

Prevalence and awareness of Hepatitis B virus infection in the United States: January 2017 - March 2020.

BACKGROUND: Prevalence and awareness of HBV infection are important national indicators of progress toward hepatitis B elimination. METHODS: National Health and Nutrition Examination Survey participants were examined for laboratory evidence of HBV infection (positive antibody to HBcAg and HBsAg), and interviewed to determine awareness of HBV infection. Estimates of HBV infection prevalence and awareness were calculated for the US population. FINDINGS: Among National Health and Nutrition Examination Survey participants aged 6 years and older evaluated from January 2017 through March 2020, an estimated 0.2% had HBV infection; of these 50% were aware of their infection.

Prevalence and Trends in Hepatitis B Virus Infection in the United States, 2015-2018.

Hepatitis B virus (HBV) is a type of viral hepatitis transmitted through sexual contact, contaminated blood, or from an infected mother to her newborn (1). HBV may cause a liver infection that is acute or short-term, but may also cause chronic or long-term infection. Vaccination was targeted to high-risk groups in 1982, and universal vaccination of newborns was recommended beginning in 1991 in the United States (2). This report provides 2015-2018 prevalence estimates of past or present HBV infection and evidence of hepatitis B vaccination, based on blood collected in the National Health and Nutrition Examination Survey (NHANES).

Vital Signs: Newly Reported Acute and Chronic Hepatitis C Cases - United States, 2009-2018.

INTRODUCTION: Hepatitis C is a leading cause of death from liver disease in the United States. Acute hepatitis C infection is often asymptomatic, and >50% of cases will progress to chronic infection, which can be life-threatening. Hepatitis C can be diagnosed with a blood test and is curable, yet new cases of this preventable disease are increasing. METHODS: National Notifiable Diseases Surveillance System data were analyzed to determine the rate of acute hepatitis C cases reported to CDC by age group and year during 2009-2018 and the number and rate of newly reported chronic cases in 2018 by sex and age. The proportion of adults aged ≥20 years with hepatitis C who reported having ever been told that they had hepatitis C was estimated with 2015-2018 National Health and Nutrition Examination Survey data. RESULTS: During 2018, a total of 3,621 cases of acute hepatitis C were reported, representing an estimated 50,300 cases (95% confidence interval [CI] = 39,800-171,600). The annual rate of reported acute hepatitis C cases per 100,000 population increased threefold, from 0.3 in 2009 to 1.2 in 2018, and was highest among persons aged 20-29 (3.1) and 30-39 years (2.6) in 2018. A bimodal distribution of newly reported chronic hepatitis C cases in 2018 was observed, with the highest proportions among persons aged 20-39 years and 50-69 years. Only 60.6% (95% CI = 46.1%-73.9%) of adults with hepatitis C reported having been told that they were infected. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Increasing rates of acute hepatitis C among young adults, including reproductive-aged persons, have put multiple generations at risk for chronic hepatitis C. The number of newly reported chronic infections was approximately equal among younger and older adults in 2018. The new CDC hepatitis C testing recommendations advise screening all adults and pregnant women, not just persons born during 1945-1965, and those with risk factors.

Susceptibility to Hepatitis A Virus Infection in the United States, 2007-2016.

BACKGROUND: Despite national immunization efforts, including universal childhood hepatitis A (HepA) vaccination recommendations in 2006, hepatitis A virus (HAV)-associated outbreaks have increased in the United States. Unvaccinated or previously uninfected persons are susceptible to HAV infection, yet the susceptibility in the US population is not well known. METHODS: Using National Health and Nutrition Examination Survey 2007-2016 data, we estimated HAV susceptibility prevalence (total HAV antibody negative) among persons aged ≥2 years. Among US-born adults aged ≥20 years, we examined prevalence, predictors, and age-adjusted trends of HAV susceptibility by sociodemographic characteristics. We assessed HAV susceptibility and self-reported nonvaccination to HepA among risk groups and the "immunization cohort" (those born in or after 2004). RESULTS: Among US-born adults aged ≥20 years, HAV susceptibility prevalence was 74.1% (95% confidence interval, 72.9-75.3%) during 2007-2016. Predictors of HAV susceptibility were age group 30-49 years, non-Hispanic white/black, 130% above the poverty level, and no health insurance. Prevalences of HAV susceptibility and nonvaccination to HepA, respectively, were 72.9% and 73.1% among persons who reported injection drug use, 67.5% and 65.2% among men who had sex with men, 55.2% and 75.1% among persons with hepatitis B or hepatitis C, and 22.6% and 25.9% among the immunization cohort. Susceptibility and nonvaccination decreased over time among the immunization cohort but remained stable among risk groups. CONCLUSIONS: During 2007-2016, approximately three-fourths of US-born adults remained HAV susceptible. Enhanced vaccination efforts are critically needed, particularly targeting adults at highest risk for HAV infection, to mitigate the current outbreaks.

Rising Trends in Emergency Department Visits Associated With Hepatitis C Virus Infection in the United States, 2006-2014.

OBJECTIVE: Emergency departments (EDs) are critical settings for hepatitis C care in the United States. We assessed trends and characteristics of hepatitis C-associated ED visits during 2006-2014. METHODS: We used data from the 2006-2014 Nationwide Emergency Department Sample to estimate numbers, rates, and costs of hepatitis C-associated ED visits, defined by either first-listed diagnosis of hepatitis C or all-listed diagnosis of hepatitis C. We assessed trends by demographic characteristics, liver disease severity, and patients' disposition by using joinpoint analysis, and we calculated the average annual percentage change (AAPC) from 2006 to 2014. RESULTS: During 2006-2014, the rate per 100 000 visits of first-listed and all-listed hepatitis C-associated ED visits increased significantly from 10.1 to 25.4 (AAPC = 13.0%; P < .001) and from 484.4 to 631.6 (AAPC = 3.4%; P < .001), respectively. Approximately 70% of these visits were made by persons born during 1945-1965 (baby boomers); 30% of visits were made by Medicare beneficiaries and 40% by Medicaid beneficiaries. Significant rate increases were among visits by baby boomers (first-listed: AAPC = 13.8%; all-listed: AAPC = 2.6%), persons born after 1965 (first-listed: AAPC = 14.3%; all-listed: AAPC = 9.2%), Medicare beneficiaries (first-listed: AAPC = 18.0%; all-listed: AAPC = 3.9%), and persons hospitalized after ED visits (first-listed: AAPC = 20.0%; all-listed: AAPC = 2.3%; all P < .001). Increasing proportions of compensated cirrhosis were among visits by baby boomers (first-listed: AAPC = 11.5%; all-listed: AAPC = 6.3%). Annual hepatitis C-associated total ED costs increased by 400.0% (first-listed) and 192.0% (all-listed) during 2006-2014. CONCLUSION: Public health efforts are needed to address the growing burden of hepatitis C care in the ED.

Sofosbuvir-Based Regimens for Chronic Hepatitis C in a Well-Insured U.S. Population: Patient Characteristics, Treatment Adherence, Effectiveness, and Health Care Costs, 2013-2015.

BACKGROUND: Chronic hepatitis C (CHC) is a leading cause of morbidity and mortality and has imposed a high health care burden in the United States. Direct-acting antiviral (DAA) regimens are well tolerated and highly effective for CHC therapy but were initially marketed at a high price. Studies of their real-world use with a nationwide population are limited. OBJECTIVE: To examine patient characteristics, treatment adherence, effectiveness, and health care costs in a large U.S. population with commercial and Medicare supplemental insurance plans who received simeprevir (SIM), sofosbuvir (SOF), or ledipasvir/sofosbuvir (LED/SOF) during the years 2013-2015. METHODS: Patients with at least 1 diagnosis code for CHC and at least 1 claim for SIM, SOF, or LED/SOF prescriptions were selected. The date of the first claim for SIM, SOF, or LED/SOF was defined as the index date. Analyses were stratified by 4 regimens: SOF + SIM ± ribavirin (RBV), SOF + peginterferon alpha-2a or 2b (PEG) + RBV, SOF + RBV, and LED/SOF ± RBV. Adherence was defined by the proportion of days covered (PDC) ≥ 80%. Sustained virologic response (SVR12) was defined as a hepatitis C virus (HCV) RNA load of ≤ 25 IU/mL measured at ≥ 12 weeks following the end of the days supply of the last DAA refill. Health care costs such as DAA drug costs and medical costs (inpatient costs plus outpatient costs) were described. RESULTS: Of 10,808 CHC patients, approximately two thirds were male, and mean age was 55 years. The proportion of patients with compensated cirrhosis among each regimen ranged from 7.4% in LED/SOF ± RBV to 13.8% in SOF + SIM ± RBV, and the proportion of patients with decompensated cirrhosis ranged from 3.9% in LED/SOF ± RBV to 10.7% in SOF + SIM ± RBV. The majority of patients (89.0%) used the newer regimen LED/SOF ± RBV in 2015. Adherence rates were estimated at 80.5%, 81.5%, 85.7%, and 91.4% for SOF + SIM ± RBV (n = 1,761); SOF + PEG + RBV (n = 1,314); SOF + RBV (n = 1,994); and LED/SOF ± RBV (n = 5,739), respectively. Regimen-specific adherence predictors included sex, age group, payer type, health plan, and treatment option with RBV. Being born during 1945-1965, liver disease severity, and Charlson Comorbidity Index levels did not predict adherence in any regimen. Overall SVR12 was 92.6% in 203 patients with available HCV RNA results: 100% (41/41) in SOF + SIM ± RBV; 83.3% (25/30) in SOF + PEG + RBV; 90.6% (29/32) in SOF + RBV; and 93% (93/100) in LED/SOF ± RBV. While the drug costs for these DAA regimens were initially high, they had decreased 18.9% (P < 0.001) during 2013-2015. Medical costs decreased 9.2% (P < 0.001) 1 year after the index dates. CONCLUSIONS: These results indicate that DAA drug costs decreased steadily during 2013-2015 and that 89% of patients on SOF-based DAA regimens took newer, lower-cost regimens with adherence rates above 80%. Available data show that SVR12 rates were close to those obtained in clinical studies. Medical costs also significantly decreased 1 year after the index dates. DISCLOSURES: No outside funding supported this study. All authors are U.S. federal employees of the Centers for Disease Control and Prevention. The authors declare that they have no competing interests. The findings and conclusions in this research are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

Hepatitis B Vaccination and Screening Among Foreign-born Women of Reproductive Age in the United States: 2013-2015.

Background: Mother-to-child transmission of hepatitis B can be prevented with vaccination and screening. Foreign-born women living in the United States may have lower vaccination coverage and greater lifetime exposure to hepatitis B virus than US-born women. This study compares self-reported hepatitis B vaccination and screening between US-born and foreign-born women of reproductive age and examines predictors. Methods: National Health Interview Survey data from 2013-2015 were pooled to estimate the prevalence of lifetime history of hepatitis B vaccination and screening self-reported by women aged 18-44 years who were born in the United States or elsewhere (foreign born). The significance of world region of birth, birth-year cohort, and immigration-related characteristics was considered. Results: Among women of reproductive age (n = 24216), the reported hepatitis B vaccination coverage rate was 33% lower for foreign-born (27.3%) than for US-born (40.9%) women (t test, P < .05). Vaccination coverage was low for women who were born in Mexico/Central America/Caribbean islands (18.4%), South America (25.3%), and the Indian subcontinent (31.7%). Education, income, and insurance coverage were associated with vaccination in both groups. Screening was reported by 28.5% of foreign-born versus 31.9% of US-born women (t test, P < .05). The lowest reported screening prevalence occurred among foreign-born Hispanic or Latina Mexican (21.0%) and Puerto Rican (21.9%) women. Factors associated with screening prevalence among foreign-born women included English fluency, recent US residency, and citizenship. Conclusions: Foreign-born women of reproductive age had lower hepatitis B vaccination and screening coverage than US-born women of reproductive age.

Estimating Prevalence of Hepatitis C Virus Infection in the United States, 2013-2016.

Hepatitis C virus (HCV) infection is the most commonly reported bloodborne infection in the United States, causing substantial morbidity and mortality and costing billions of dollars annually. To update the estimated HCV prevalence among all adults aged ≥18 years in the United States, we analyzed 2013-2016 data from the National Health and Nutrition Examination Survey (NHANES) to estimate the prevalence of HCV in the noninstitutionalized civilian population and used a combination of literature reviews and population size estimation approaches to estimate the HCV prevalence and population sizes for four additional populations: incarcerated people, unsheltered homeless people, active-duty military personnel, and nursing home residents. We estimated that during 2013-2016 1.7% (95% confidence interval [CI], 1.4-2.0%) of all adults in the United States, approximately 4.1 (3.4-4.9) million persons, were HCV antibody-positive (indicating past or current infection) and that 1.0% (95% CI, 0.8-1.1%) of all adults, approximately 2.4 (2.0-2.8) million persons, were HCV RNA-positive (indicating current infection). This includes 3.7 million noninstitutionalized civilian adults in the United States with HCV antibodies and 2.1 million with HCV RNA and an estimated 0.38 million HCV antibody-positive persons and 0.25 million HCV RNA-positive persons not part of the 2013-2016 NHANES sampling frame. Conclusion: Over 2 million people in the United States had current HCV infection during 2013-2016; compared to past estimates based on similar methodology, HCV antibody prevalence may have increased, while RNA prevalence may have decreased, likely reflecting the combination of the opioid crisis, curative treatment for HCV infection, and mortality among the HCV-infected population; efforts on multiple fronts are needed to combat the evolving HCV epidemic, including increasing capacity for and access to HCV testing, linkage to care, and cure.

Prevalence of Hepatitis C Virus Infection in US States and the District of Columbia, 2013 to 2016.

Importance: Infection with hepatitis C virus (HCV) is a major cause of morbidity and mortality in the United States, and incidence has increased rapidly in recent years, likely owing to increased injection drug use. Current estimates of prevalence at the state level are needed to guide prevention and care efforts but are not available through existing disease surveillance systems. Objective: To estimate the prevalence of current HCV infection among adults in each US state and the District of Columbia during the years 2013 to 2016. Design, Setting, and Participants: This survey study used a statistical model to allocate nationally representative HCV prevalence from the National Health and Nutrition Examination Survey (NHANES) according to the spatial demographics and distributions of HCV mortality and narcotic overdose mortality in all National Vital Statistics System death records from 1999 to 2016. Additional literature review and analyses estimated state-level HCV infections among populations not included in the National Health and Nutrition Examination Survey sampling frame. Exposures: State, accounting for birth cohort, biological sex, race/ethnicity, federal poverty level, and year. Main Outcomes and Measures: State-level prevalence estimates of current HCV RNA. Results: In this study, the estimated national prevalence of HCV from 2013 to 2016 was 0.84% (95% CI, 0.75%-0.96%) among adults in the noninstitutionalized US population represented in the NHANES sampling frame, corresponding to 2 035 100 (95% CI, 1 803 600-2 318 000) persons with current infection; accounting for populations not included in NHANES, there were 231 600 additional persons with HCV, adjusting prevalence to 0.93%. Nine states contained 51.9% of all persons living with HCV infection (California [318 900], Texas [202 500], Florida [151 000], New York [116 000], Pennsylvania [93 900], Ohio [89 600], Michigan [69 100], Tennessee [69 100], and North Carolina [66 400]); 5 of these states were in Appalachia. Jurisdiction-level median (range) HCV RNA prevalence was 0.88% (0.45%-2.34%). Of 13 states in the western United States, 10 were above this median. Three of 10 states with the highest HCV prevalence were in Appalachia. Conclusions and Relevance: Using extensive national survey and vital statistics data from an 18-year period, this study found higher prevalence of HCV in the West and Appalachian states for 2013 to 2016 compared with other areas. These estimates can guide state prevention and treatment efforts.

Prevalence of past-year dental visit among US adults, 1999-2010: comparison of trends and estimates between the Behavioral Risk Factor Surveillance System and three national surveys.

OBJECTIVES: To compare estimated prevalence of past-year dental visit (PPYDV) among US adults aged ≥18 years from the Behavioral Risk Factor Surveillance System (BRFSS) to estimates from the Medical Expenditure Panel Survey (MEPS), National Health Interview Survey (NHIS), and National Health and Nutrition Examination Survey (NHANES). METHODS: We estimated PPYDV adjusted for covariates (age, race/ethnicity, education level, poverty status, edentulism) using BRFSS, MEPS, and NHIS 1999-2010, and NHANES 1999-2004. We tested trend in overall PPYDV for BRFSS, MEPS, and NHIS from 1999-2010. For 2002 and 2010, we calculated absolute differences (AD) and 95% confidence intervals (CI) in PPYDV between BRFSS and each of the other surveys overall and among subpopulations defined by covariates. We pooled NHANES 1999-2004 data for comparison with BRFSS 2002. RESULTS: From 1999 to 2010, BRFSS (68.5% vs. 67.5%), MEPS (43.5% vs. 39.7%), and NHIS (63.3% vs. 59.7%) showed small but significant decreases in overall PPYDV. In 2002, estimates for overall PPYDV were highest for BRFSS (70.0%) and lowest for MEPS (43.9%) with estimates for NHIS (61.5%) and NHANES (1999-2004: 58.1%) in between; the largest AD (26.2%, 95% CI: 25.0%-27.3%) was between BRFSS and MEPS. ADs were consistent in 2002 and 2010, overall and by covariates, except among edentate persons, where PPYDV estimates from BRFSS and NHIS were similar. CONCLUSIONS: Estimates of PPYDV from BRFSS were notably higher than estimates from MEPS, NHIS, or NHANES except among the edentate. Trends in PPYDV over time, however, were consistent across all surveys.

The effect of health and dental insurance on US children's dental care utilization for urgent and non-urgent dental problems - 2008.

OBJECTIVE: We examined the association between utilization of care for a dental problem (utilization-DP) and parent-reported dental problem (DP) urgency among children with DP by type of health care insurance coverage. METHODS: We used weighted 2008 National Health Interview Survey data from 2,834 children, aged 2-17 years with at least one DP within the 6 months preceding survey. Explanatory variables were selected based on Andersen's model of healthcare utilization. Need was considered urgent if DP included toothache, bleeding gums, broken or missing teeth, broken or missing filling, or decayed teeth and otherwise as non-urgent. The primary enabling variable, insurance, had four categories: none, private health no dental coverage (PHND), private health and dental (PHD), or Medicaid/State Children's Health Insurance Program (SCHIP). Predisposing variables included sociodemographic characteristics. We used bivariate and multivariate analyses to identify explanatory variables' association with utilization-DP. Using logistic regression, we obtained adjusted estimates of utilization-DP by urgency for each insurance category. RESULTS: In bivariate analyses, utilization-DP was associated with both insurance and urgency. In multivariate analyses, the difference in percent utilizing care for an urgent versus non-urgent DP among children covered by Medicaid/SCHIP was 32 percentage points; PHD, 25 percentage points; PHND, 12 percentage points; and no insurance, 14 percentage points. The difference in utilization by DP urgency was higher for children with Medicaid/SCHIP compared with either PHND or uninsured children. CONCLUSION: Expansion of Medicaid/SCHIP may permit children to receive care for urgent DPs who otherwise may not, due to lack of dental insurance.

Adjusted fluoride concentrations and control ranges in 34 states - 2006-2010 and 2015.

To inform selection of a control range around the Public Health Service's recommended 0.7 mg/L drinking water fluoride concentration to prevent tooth decay, CDC's Water Fluoridation Reporting System data for 2006-2010 and 2015 were analyzed. Monthly average concentration data from 4,251 fluoride-adjusted community water systems for 191,266 of 255,060 system-months (2006-2010) were compared to control ranges 0.6 mg/L to 0.2 mg/L wide. Percentages of system-months within control ranges ≥0.4 mg/L wide (e.g., ±0.2 mg/L) were >83% versus 68% for 0.2 mg/L wide (±0.1 mg/L). In 2015, 70% of adjusted systems maintained averages within ±0.1 mg/L of their system's annual average for 9 of 12 months, 67% used the 0.7 mg/L target and 45% used it with a ±0.1 mg/L control range. Adoption of the 0.7 mg/L target was underway but not completed in 2015. Control ranges narrower than ±0.2 mg/L may be feasible for monthly average fluoride concentration.

Water Intake by Outdoor Temperature Among Children Aged 1-10 Years: Implications for Community Water Fluoridation in the U.S.

OBJECTIVE: The U.S. water fluoridation recommendations, which have been in place since 1962, were based in part on findings from the 1950s that children's water intake increased with outdoor temperature. We examined whether or not water intake is associated with outdoor temperature. METHODS: Using linked data from the National Health and Nutrition Examination Survey (NHANES) 1999-2004 and the National Oceanic and Atmospheric Administration, we examined reported 24-hour total and plain water intake in milliliters per kilogram of body weight per day of children aged 1-10 years by maximum outdoor temperature on the day of reported water intake, unadjusted and adjusted for age, sex, race/ethnicity, and poverty status. We applied linear regression methods that were used in previously reported analyses of data from NHANES 1988-1994 and from the 1950s. RESULTS: We found that total water intake was not associated with temperature. Plain water intake was weakly associated with temperature in unadjusted (coefficient 5 0.2, p=0.015) and adjusted (coefficient 5 0.2, p=0.013) linear regression models. However, these models explained little of the individual variation in plain water intake (unadjusted: R(2)=0.005; adjusted: R(2)=0.023). CONCLUSION: Optimal fluoride concentration in drinking water to prevent caries need not be based on outdoor temperature, given the lack of association between total water intake and outdoor temperature, the weak association between plain water intake and outdoor temperature, and the minimal amount of individual variance in plain water intake explained by outdoor temperature. These findings support the change in the U.S. Public Health Service recommendation for fluoride concentration in drinking water for the prevention of dental caries from temperature-related concentrations to a single concentration that is not related to outdoor temperature.

Advancing infection control in dental care settings: factors associated with dentists' implementation of guidelines from the Centers for Disease Control and Prevention.

BACKGROUND AND OVERVIEW: The authors set out to identify factors associated with implementation by U.S. dentists of four practices first recommended in the Centers for Disease Control and Prevention's Guidelines for Infection Control in Dental Health-Care Settings-2003. METHODS: In 2008, the authors surveyed a stratified random sample of 6,825 U.S. dentists. The response rate was 49 percent. The authors gathered data regarding dentists' demographic and practice characteristics, attitudes toward infection control, sources of instruction regarding the guidelines and knowledge about the need to use sterile water for surgical procedures. Then they assessed the impact of those factors on the implementation of four recommendations: having an infection control coordinator, maintaining dental unit water quality, documenting percutaneous injuries and using safer medical devices, such as safer syringes and scalpels. The authors conducted bivariate analyses and proportional odds modeling. RESULTS: Responding dentists in 34 percent of practices had implemented none or one of the four recommendations, 40 percent had implemented two of the recommendations and 26 percent had implemented three or four of the recommendations. The likelihood of implementation was higher among dentists who acknowledged the importance of infection control, had practiced dentistry for less than 30 years, had received more continuing dental education credits in infection control, correctly identified more surgical procedures that require the use of sterile water, worked in larger practices and had at least three sources of instruction regarding the guidelines. Dentists with practices in the South Atlantic, Middle Atlantic or East South Central U.S. Census divisions were less likely to have complied. CONCLUSIONS: Implementation of the four recommendations varied among U.S. dentists. Strategies targeted at raising awareness of the importance of infection control, increasing continuing education requirements and developing multiple modes of instruction may increase implementation of current and future Centers for Disease Control and Prevention guidelines.

Comparison of ArcGIS and SAS Geostatistical Analyst to Estimate Population-Weighted Monthly Temperature for US Counties.

Temperature changes are known to have significant impacts on human health. Accurate estimates of population-weighted average monthly air temperature for US counties are needed to evaluate temperature's association with health behaviours and disease, which are sampled or reported at the county level and measured on a monthly-or 30-day-basis. Most reported temperature estimates were calculated using ArcGIS, relatively few used SAS. We compared the performance of geostatistical models to estimate population-weighted average temperature in each month for counties in 48 states using ArcGIS v9.3 and SAS v 9.2 on a CITGO platform. Monthly average temperature for Jan-Dec 2007 and elevation from 5435 weather stations were used to estimate the temperature at county population centroids. County estimates were produced with elevation as a covariate. Performance of models was assessed by comparing adjusted R2, mean squared error, root mean squared error, and processing time. Prediction accuracy for split validation was above 90% for 11 months in ArcGIS and all 12 months in SAS. Cokriging in SAS achieved higher prediction accuracy and lower estimation bias as compared to cokriging in ArcGIS. County-level estimates produced by both packages were positively correlated (adjusted R2 range=0.95 to 0.99); accuracy and precision improved with elevation as a covariate. Both methods from ArcGIS and SAS are reliable for U.S. county-level temperature estimates; However, ArcGIS's merits in spatial data pre-processing and processing time may be important considerations for software selection, especially for multi-year or multi-state projects.

Overview and quality assurance for the oral health component of the National Health and Nutrition Examination Survey (NHANES), 2005-08.

The oral health component for the National Health and Nutrition Examination Survey (NHANES) was changed in 2005 from an examination conducted by dentists to an oral health screening conducted by health technologists rather than dental professionals. The oral health screening included a person-based assessment for dental caries, restorations, and sealants. This report provides oral health content information and presents results of data quality analyses that include dental examiner reliability statistics for data collected during NHANES 2005-08. Oral health data are available on 15,342 persons aged 5 years and older representing the civilian, noninstitutionalized population of the United States who participated in NHANES 2005-08. Overall, interrater reliability findings indicate that health technologist performance was excellent with concordance between examination teams and the survey reference examiner being almost perfect for a number of assessments. Concordance for dental caries and sealants (kappa statistics) between health technologists and the survey reference examiner ranged from 0.82 to 0.90 for the combined 4-year period. These findings support the use of health technologists in the assessment of person-based estimators of dental caries and sealant prevalence as part of an oral health surveillance system.