Association of infection with Toxoplasma gondii and Toxocara on cognitive function among US adults aged 60 and over, NHANES 2011-2014.

BACKGROUND: Toxoplasma gondii and Toxocara are common parasites that infect humans globally. Our aim was to examine the relationship between T. gondii and Toxocara infection and cognition. METHODS: Multivariate logistic regression was used to test the association of T. gondii and Toxocara seropositivity on indices of cognitive function (a word list learning trial with delayed recall from the Consortium to Establish a Registry for Alzheimer's Disease, an animal fluency test (AFT) and a digit symbol substitution test (DSST)) among 2643 adults aged 60 years and older in the 2011-2014 National Health and Nutrition Examination Survey. RESULTS: Seropositivity to T. gondii or Toxocara were both associated with lower scores in all three cognitive function measures examined in univariate analyses. Except for the DSST, these associations were not significant after adjustment for age, gender, race and Hispanic origin, poverty level, education, US birth status, depression and hypertension. On stratification to account for significant interactions, Toxocara seropositivity was associated with worse scores on the AFT among those born outside the USA, worse scores on the DSST among those aged 60-69 years, female, Hispanic and with a high school diploma or less. Lower DSST scores with Toxocara infection was greater for adults living below compared with at or above the poverty level. CONCLUSIONS: Seropositivity to these parasites, particularly to Toxocara, may be associated with diminished cognitive performance in certain subgroups of older adults.

SARS-CoV-2 Serology and Self-Reported Infection Among Adults - National Health and Nutrition Examination Survey, United States, August 2021-May 2022.

CDC COVID-19 surveillance systems monitor SARS-CoV-2 antibody prevalence to collect information about asymptomatic, undiagnosed, and unreported disease using national convenience samples of blood donor data from commercial laboratories (1,2). However, nonrandom sampling of data from these systems could affect prevalence estimates (1-3). The National Health and Nutrition Examination Survey (NHANES) collects SARS-CoV-2 serology data among a sample of the general U.S. civilian population (4). In addition, NHANES collects self-reported COVID-19 vaccination and disease history, and its statistical sampling design is not based on health care access or blood donation. Therefore, NHANES data can be used to better quantify asymptomatic SARS-CoV-2 infection prevalence and seropositivity attained through infection without vaccination. Preliminary NHANES 2021-2022 results indicated that 41.6% of adults aged ≥18 years had serology indicative of past infection and that 43.7% of these adults, including 57.1% of non-Hispanic Black or African American (Black) adults, reported never having had COVID-19, possibly representing asymptomatic infection. In addition, 25.5% of adults whose serology indicated past infection reported never having received COVID-19 vaccination. Prevalences of seropositivity in the absence of vaccination were higher among younger adults and Black adults, reflecting the lower observed vaccination rates among these groups (5). These findings raise health equity concerns given the disparities observed in SARS-CoV-2 infection and COVID-19 vaccination. Results from NHANES 2021-2022 can guide ongoing efforts to achieve vaccine equity in COVID-19 primary vaccination series and booster dose coverage.

Mean Body Weight, Height, Waist Circumference, and Body Mass Index Among Children and Adolescents: United States, 1999-2018.

Objective-This report presents trends in mean weight, recumbent length, height, waist circumference, and body mass index (BMI) among children and adolescents in the United States from 1999 through 2018.

Prevalence of Urogenital Mycoplasma genitalium Infection, United States, 2017 to 2018.

ABSTRACT: During the 2017-2018 National Health and Nutrition Examination Survey, urine samples from participants aged 14 to 59 years were tested for Mycoplasma genitalium infection. Overall prevalence was 1.7% (95% confidence interval [CI], 1.1%-2.7%). Prevalence was similar between males (1.8% [95% CI, 0.9%-3.1%]) and females (1.7% [95% CI, 0.8%-3.0%]).

Prevalence and Trends in HIV Infection and Testing Among Adults in the United States: The National Health and Nutrition Examination Surveys, 1999-2018.

BACKGROUND: HIV antibody testing has been included in the National Health and Nutrition Examination Survey, for ages 18-49 since 1999 and for ages 18-59 years since 2009 enabling estimation of trends in HIV prevalence as part of national surveillance in the U.S. household population. Self-reported HIV testing and antiretroviral use was also included in the survey since 1999. SETTING: A continuous household-based probability sample of the U.S. population. METHODS: From 1999 to 2018, 29,020 participants age 18-49 years were tested for HIV antibody and 34,092 participants age 18-59 years were asked about self-report of any previous HIV testing. RESULTS: HIV prevalence was 0.41% among those aged 18-59 in 2009-2018 with a nonsignificant trend over time among those aged 18-49 years from 1999-2002 to 2015-2018. However, significant declines in prevalence were seen among those aged 18-39 years (0.37%-0.11%), women (0.22%-0.06%) and non-Hispanic black persons (2.14%-0.80%). Participants aged 18-39 years self-reported a decline in HIV testing, whereas those aged 40-49 and 50-59 years, non-Hispanic black persons and women reported an increase in getting a HIV test. Prevalence of infection and self-reported history of HIV testing varied by demographic and risk groups. HIV testing among HIV-positive persons was 83.9%. Antiretroviral therapy among those HIV-positive was under 50%. CONCLUSION: Although total HIV prevalence and previous self-reported HIV testing remained stable for the last 20 years, there were significant declines in age and demographic subgroups. Prevalence for both outcomes varied by demographic and risk variables.

Assessing consent for and response to health survey components in an era of falling response rates: National Health and Nutrition Examination Survey, 2011-2018.

Response rates for national population-based surveys have declined, including the National Health and Nutrition Examination Survey (NHANES). Declining response to the initial NHANES interview may impact consent and participation in downstream survey components such as record linkage, physical exams, storage of biological samples and phlebotomy. Interview response rates dropped from 68% in 2011-2012 to 53% in 2017-2018 for adults age 18 and older. Response was higher for children (1-17 years) but with a similar downward trend (2011-2012, 81%; 2017-2018, 65%). Despite declining interview response rates, changes in consent and response rates for downstream components over time have been mixed. Among those interviewed, the examination response rate was over 93%, consent for record linkage was over 90%, and consent for storage of specimens for future research was over 99%. The availability of a blood sample for storage ranged between 60%-65% for children and 78%-85% for adults.

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).

Trends in Apolipoprotein B, Non-high-density Lipoprotein Cholesterol, and Low-density Lipoprotein Cholesterol for Adults Aged 20 and Over, 2005-2016.

Objectives-Guidelines for lowering cholesterol have focused on total and lowdensity lipoprotein cholesterol (LDL-C). Although the emphasis remains on LDL-C, more attention is now being given to apolipoprotein B (apo B) and non-high-density lipoprotein cholesterol (non-HDL-C). This report presents trends in mean apo B, non-HDL-C, and LDL-C in adults aged 20 and over from 2005-2006 through 2015-2016. Methods-Data from the 2005-2016 National Health and Nutrition Examination Surveys were used to conduct trend analyses. Means and standard errors of the mean for apo B (n = 13,802), non-HDL-C (n = 30,921), and LDL-C (n = 13,559) are presented overall and by sex, stratified by age, race and Hispanic origin, and body mass index (BMI) category for each 2-year survey cycle. Trends over time were tested using orthogonal contrast matrices and piecewise and multiple linear regression. Results-In men, apo B declined from 98 mg/dL in 2005-2006 to 93 mg/dL in 2011-2012, but did not change after 2011-2012. Declining trends were also seen for men in non-HDL-C (147 to 141 mg/dL) and LDL-C (116 to 114 mg/dL) from 2005-2006 to 2015-2016. For women, age-adjusted mean apo B declined from 94 mg/dL in 2005-2006 to 91 mg/dL in 2015-2016. Non-HDL-C and LDL-C in women did not change significantly from 2005-2006 to 2011-2012, but non-HDL-C declined from 141 mg/dL in 2011-2012 to 133 mg/dL in 2015-2016, and LDL-C declined from 117 mg/dL in 2011-2012 to 111 mg/dL in 2015-2016. With the exception of LDL-C in men, these trends persisted after controlling for age, race and Hispanic origin, BMI, and lipid-lowering medication use. Conclusions-From 2005-2006 to 2015-2016, significant but different declining trends in apo B, non-HDL-C, and LDL-C were seen in men and women. In general, differences in age, race and Hispanic origin, BMI category, and lipid-lowering medication use did not explain the trends.

National Center for Health Statistics Guidelines for Analysis of Trends.

Many reports present analyses of trends over time based on multiple years of data from National Center for Health Statistics (NCHS) surveys and the National Vital Statistics System (NVSS). Trend analyses of NCHS data involve analytic choices that can lead to different conclusions about the trends. This report discusses issues that should be considered when conducting a time trend analysis using NCHS data and presents guidelines for making trend analysis choices. Trend analysis issues discussed include: choosing the observed time points to include in the analysis, considerations for survey data and vital records data (record level and aggregated), a general approach for conducting trend analyses, assorted other analytic issues, and joinpoint regression. This report provides 12 guidelines for trend analyses, examples of analyses using NCHS survey and vital records data, statistical details for some analysis issues, and SAS and SUDAAN code for specification of joinpoint regression models. Several an lytic choices must be made during the course of a trend analysis, and the choices made can affect the results. This report highlights the strengths and limitations of different choices and presents guidelines for making some of these choices. While this report focuses on time trend analyses, the issues discussed and guidelines presented are applicable to trend analyses involving other ordinal and interval variables.

Prevalence of Herpes Simplex Virus Type 1 and Type 2 in Persons Aged 14-49: United States, 2015-2016.

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are common, lifelong infections, which often have no symptoms (1). People with symptoms may have painful blisters or sores at the site of infection (2,3). The viruses are transmitted through contact with an infected person's lesion, mucosal surface, or genital or oral secretions. This report provides recent national estimates of HSV-1 and HSV-2 antibody prevalence from the 2015­2016 National Health and Nutrition Examination Survey (NHANES) among persons aged 14­49 by age, sex, and race and Hispanic origin, and examines trends in prevalence by race and Hispanic origin from 1999­2000 to 2015­2016.

Viral and parasitic pathogen burden and the association with stroke in a population-based cohort.

Background Higher cumulative burden of viral and bacterial pathogens may increase the risk of stroke, but the contribution of parasitic infections in relation to cumulative pathogen burden and risk of stroke has rarely been examined. Aim To estimate the association of multiple persistent viral and parasitic infections with stroke in a representative sample of adults in the United States. Methods Serological evidence of prior infection was categorized as positive for 0-1, 2, 3, or 4-5 infections based on immunoglobulin G seropositivity to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. in 13,904 respondents from the National Health and Nutrition Examination Survey III. Regression analysis was used to estimate the cross-sectional association between serological evidence of prior infection and history of stroke adjusting for demographic risk factors, and potential mediators of stroke. Results Age-adjusted models that included serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. showed that adults in the highest serological evidence of prior infection category (4-5 infections) had a higher prevalence of stroke (5.50%, 95% confidence interval 2.44-10.46%) than those in the lowest serological evidence of prior infection categories (1.49%, 95% confidence interval 1.01-2.11%), and a trend test suggested a graded association between serological evidence of prior infection and stroke ( p = 0.02). In multivariable logistic regression models, the positive association of serological evidence of prior infection with stroke prevalence remained significant after adjustment for other significant risk factors (odds ratio = 1.4, p = 0.01) but was only significant among those aged 20-59 (odds ratio = 2.0, p = 0.005) and not among those aged 60-69 ( p = 0.78) or 70 and older ( p = 0.43). Conclusion We found support for a connection between serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. and stroke among those aged 20-59. There may be a need to consider common parasitic infections in addition to viral and bacterial pathogens when calculating serological evidence of prior infection in relation to cerebrovascular disease.

Toxoplasma gondii Infection in the United States, 2011-2014.

Toxoplasma gondii can cause severe neurologic and ocular disease when transmitted congenitally and in immunosuppressed persons. Sera collected in the National Health and Nutrition Examination Survey 2011 through 2014 in 13,507 persons ≥ 6 years old were tested for T. gondii immunoglobulin (Ig) G and IgM antibodies, and in those both IgG and IgM antibody positive, for IgG avidity. Overall, 11.14% (95% confidence limits [CL] 9.88%, 12.51%) were seropositive for T. gondii IgG antibody (age-adjusted seroprevalence 10.42% [95% CL 9.19%, 11.76%]); in women aged 15-44 years, the age-adjusted T. gondii IgG seroprevalence was 7.50% (95% CL 6.00%, 9.25%). In multivariable analysis, risk for IgG seropositivity increased with age and was higher in males; persons living below the poverty level; persons with ≤ a high school education compared with those with > a high school education; and non-Hispanic black, Mexican American, and foreign born non-Hispanic white persons compared with U.S.-born non-Hispanic white persons. Overall, 1.16% (95% CL 0.94%, 1.42%) were T. gondii IgM antibody positive and 0.71%, (95% CL 0.54%, 0.92%) were both IgM and IgG antibody positive. In multivariable analysis, the significant risk factors for being both IgM and IgG positive were older age, crowding, and non-U.S. birth origin compared with U.S.-born persons. Among those positive for both IgM and IgG antibody, almost all had high avidity (all women aged 15-44 years had high avidity). Toxoplasma gondii antibody prevalence remains relatively low in the United States, although it is higher in non-U.S.-born persons, males, and some minority and socioeconomically disadvantaged groups.

Seroprevalence of Antibodies to Toxocara Species in the United States and Associated Risk Factors, 2011-2014.

Background: Toxocariasis results from infection with larval stages of a dog and cat intestinal nematode and causes human morbidity. The current United States estimate of Toxocara exposure is 13.9% (National Health and Nutrition Examination Survey [NHANES] III [1988-1994]). Methods: We used a multiplex bead-based assay (Tc-CTL-1MBA) with purified Toxocara canis antigen to estimate Toxocara antibody seroprevalence in serum of 13 509 persons aged ≥6 years from NHANES 2011-2014 and identified seropositivity risk factors. We tested a subset of 500 samples with the T. canis enzyme immunoassay used in NHANES III to estimate prior seroprevalence had samples from NHANES III been tested by Tc-CTL-1MBA. Results: The age-standardized estimate of Toxocara seroprevalence was 5.0% (95% confidence interval [CI], 4.2%-5.8%), lower than previously reported even after adjusting for increased Tc-CTL-1MBA specificity. Risk factors for seropositivity from multiple logistic regression were older age, non-Hispanic black/Hispanic origin, male sex, living below poverty level, households with ≥0.5 persons per room, less than college education, and birth outside of the United States. Conclusions: Toxocara seroprevalence estimates in 2011-2014 were lower than in a study from NHANES III (1988-1994), but seropositivity risk factors remained the same and should continue to be the focus of prevention efforts.

Mean Body Weight, Height, Waist Circumference, and Body Mass Index Among Adults: United States, 1999-2000 Through 2015-2016.

Objectives-This report presents trends in mean weight, height, waist circumference, and body mass index (BMI) among adults in the United States from 1999-2000 through 2015-2016. Methods-Data were obtained from physical examinations of a nationally representative sample of adults aged 20 and over in the National Health and Nutrition Examination Surveys during 1999-2016. The tables present means and standard errors of the mean for weight (n = 45,047), height (n = 46,481), waist circumference (n = 43,169), and BMI (n = 44,859) separately for men and women overall, by age group, and by race and Hispanic origin for each 2-year survey period. Changes in these body measures over time were evaluated using linear regression. Results-Since 1999, mean weight, waist circumference, and BMI increased for all age groups, for non-Hispanic white and Mexican-American men and women, and for non-Hispanic black women. Among non-Hispanic black men, weight, waist circumference, and BMI increased until 2005-2006 and then remained level. No change in height was seen over time except for a decrease in crude estimates among all women, a decrease among men and women aged 40-59, and an increase in both crude and age-adjusted estimates of mean height for men followed by a decrease after 2003-2004. No significant trends were seen in any of the four body measures for non-Hispanic Asian men and women (data available only for 2011-2016).

Prevalence, Change Over Time, and Comparison With U.S. Estimates of Selected Infectious Diseases in Los Angeles County: Findings From the National Health and Nutrition Examination Survey, 1999-2006 and 2007-2014.

Objective-This report compares prevalence of and change over time for five infectious disease outcomes for the Los Angeles County (LAC) and the U.S. populations. The infectious disease outcomes examined are: herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), any hepatitis B virus (HBV) infection, HBV immunization, and hepatitis A virus (HAV) from infection or immunization, available for 1999-2006 and 2007-2014, as well as any human papillomavirus (HPV) and high-risk HPV infection, available for the 2007-2014 period only. Methods-LAC was sampled in every 2-year cycle of the current National Health and Nutrition Examination Survey, enabling creation of two 8-year samples (1999-2006 and 2007-2014). Demographic differences associated with disease prevalence were examined between LAC and the United States. Changes over time and differences in prevalence, unadjusted, age adjusted, and "fully" adjusted by direct standardization for these demographic variables, were evaluated between the United States and LAC for 2007-2014. Results-Compared with the United States, persons in LAC were more likely to be Mexican American, born outside of the United States, and live below the poverty level. Prevalence varied significantly by demographic subgroup for each outcome in the United States and for some outcomes in LAC. Differences between LAC and the United States existed for some outcomes but varied with adjustment. Over time, prevalence of HSV-1, HSV-2, and HBV infection decreased, and HBV immunization and HAV infection or immunization increased for the U.S. population. The direction of changes over time were mostly similar for LAC, but significance varied.

Hypertension Prevalence and Control Among Adults: United States, 2015-2016.

Hypertension remains an important public health challenge in the United States because it increases the risk for cardiovascular disease. Effective blood pressure management has been shown to decrease the incidence of stroke, heart attack, and heart failure (1­3). This report presents updated estimates for the prevalence and control of hypertension in the United States for 2015­2016. Trends in hypertension prevalence and control from 1999­2000 through 2015­2016 are also presented.