Search

Background. Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are common infections with serious sequelae. HSV-1 is an increasingly important cause of genital herpes in industrialized countries.Methods. Using nationally representative data from the National Health and Nutrition Examination Survey (NHANES), we examined HSV-1 and HSV-2 seroprevalence among 14- to 49-year-olds in the United States. We estimated seroprevalence in 1999–2004 and 2005–2010, stratified by sociodemographic characteristics and sexual behaviors. We also reviewed HSV-1 and HSV-2 seroprevalence from 1976–1980 to 2005–2010.Results. In 2005–2010, the seroprevalence of HSV-1 was 53.9%, and the seroprevalence of HSV-2 was 15.7%. From 1999–2004 to 2005–2010, HSV-1 seroprevalence declined by nearly 7% (P < .01), but HSV-2 seroprevalence did not change significantly. The largest decline in HSV-1 seroprevalence from 1999–2004 to 2005–2010 was observed among adolescents aged 14–19 years, among whom seroprevalence declined by nearly 23%, from 39.0% to 30.1% (P < .01). In this age group, HSV-1 seroprevalence declined >29% from 1976–1980 to 2005–2010 (P < .01).Conclusions. An increasing number of adolescents lack HSV-1 antibodies at sexual debut. In the absence of declines in HSV-2 infections, the prevalence of genital herpes may increase. [ABSTRACT FROM PUBLISHER]

Objectives. We described seroprevalence of antibody to hepatitis A virus (anti- HAV) in the United States during 1999-2006 and compared it with seroprevalence before the availability of vaccine. Methods. We analyzed data from the 1988-1994 and 1999-2006 National Health and Nutrition Examination Survey (NHANES) to obtain estimates of anti- HAV seroprevalence for the U.S. household population. We grouped region of residence based on the 1999 Advisory Committee on Immunization Practices recommendations into 17 states with any recommendation (vaccinating) and 33 states without any recommendation (non-vaccinating). Results. During 1999-2006, the overall seroprevalence of anti-HAV was 34.9% (95% confidence interval [CI] 33.1, 36.7). During 1999-2006, U.S.-born children living in vaccinating states (33.8%, 95% CI 26.2, 42.2) had a higher seroprevalence than children in non-vaccinating states (11.0%, 95% CI 9.4, 12.8; p<0.001). Seroprevalence among children increased from 8.0% (95% CI 6.3, 10.1) during 1988-1994 to 20.2% (95% CI 16.0, 24.8) during 1999-2006 (p<0.001). For U.S.-born children aged 6-19 years, the strongest factor associated with seroprevalence was residence in vaccinating states. Among U.S.-born adults aged >19 years, the overall age-adjusted seroprevalence of. anti-HAV was 29.9% (95% CI 28.3, 31.5) during 1999-2006, which was not significantly different from the seroprevalence during 1988-1994 (32.2%, 95% CI 30.1, 34.4). Conclusions. Increases in seroprevalence among children in vaccinating states suggest a positive effect of the 1999 vaccination recommendations. [ABSTRACT FROM AUTHOR]

Objective. We estimated the varicella seroprevalence among the U.S. Population aged 6-49 years based on retested National Health and Nutrition Examination Survey (NHANES) specimens collected between 1999 and 2004—originally tested using a method unsuitable for detecting vaccine-induced immunity—and compared it with historical estimates. Methods. We performed a confirmatory test suitable for, detecting vaccine-induced immunity on all available specimens from 6- to 19-year-olds who originally tested negative (n=633), and on 297 randomly selected specimens that had tested positive. Retest results superseded original results for determining seroprevalence. We assessed seroprevalence for the entire sample aged 6-49 years (n=16,050) by participant demographic characteristics and compared it with historical estimates (NHANES 1988-1994). Results. The percentage of false-negative results for the original test was higher for specimens from younger children (6-11 years of age: 27.5%; 12-19 years of age: 13.3%) and for specimens collected most recently (2001-2004: 26.0%; 1999-2000: 12.6%). The age-adjusted rate of varicella seroprevalence for 1999-2004 was 93.6% for 6- to 19-year-olds and 98.0% for adults aged 20-49 years compared with 90.0% and 98.1%, respectively, for 1988-1994. We found an increase in seropositivity between the survey periods, from 93.2% to 97.2% (p<0.001) among 12- to 19-year-olds. For children, non-Hispanic black ethnicity and younger age were associated with lower seroprevalence in both survey periods. Conclusions. Varicella seroprevalence increased with age among children and was uniformly high in the U.S. adult population between 1999 and 2004. The original testing produced false-negative seroprevalence results among children's specimens collected between 1999 and 2004 from 6- to 19-year-olds. [ABSTRACT FROM AUTHOR]

To monitor trends in HIV seroprevalence in the United States, HIV testing was included in the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2006.From 1999 to 2006, 11,928 participants aged 18-49 years were tested for HIV antibody. Prevalence estimates were weighted to account for oversampling and nonresponse.There were 67 HIV antibody-reactive individuals for a seroprevalence of 0.5% [95% confidence interval (CI) 0.3-0.6]. In the only age subgroup directly comparable between surveys (18-39 years), HIV seroprevalence remained constant from NHANES III (1988-1994) to NHANES 1999-2002 and 2003-2006. In NHANES 1999-2006, non-Hispanic blacks had significantly higher HIV seroprevalence (2.0%, 95% CI 1.5-2.7) compared with individuals in all other race/ethnic groups combined. Seroprevalence was also higher in each race/ethnic group among men who have sex with men (9.4% 95% CI 5.0-17.1), among persons who had detectable antibody to herpes simplex type-two (1.9% 95% CI 1.4-2.8), among those who had 50 or more lifetime sex partners (3.4%, 95% CI 1.7-6.7), and among those who never married (0.8%, 95% CI 0.5-1.3).In this household-based population, seroprevalence did not significantly change from NHANES III to NHANES 1999-2006. Non-Hispanic blacks had significantly higher prevalence of infection compared with other race/ethnic groups. Male-to-male sex and the presence of HSV-2 antibody were the strongest predictors of HIV infection. [ABSTRACT FROM AUTHOR]

Background. Hepatitis E virus (HEV) is prevalent and causes disease worldwide, but its epidemiological profile is only partially understood. Methods. We used an enzyme immunoassay to measure anti-HEV immunoglobulin G antibodies in 18,695 serum samples collected in the Third National Health and Nutrition Examination Survey. We calculated estimates of HEV seroprevalence and examined associations with putative risk factors. Results. The seroprevalence of HEV in the civilian noninstitutionalized United States (US) population during the period from 1988 through 1994 was 21.0% (95% confidence interval [CI], 19.0%-22.9%). Among US-born individuals, males, non-Hispanic whites, and individuals residing in the Midwest and/or in metropolitan areas had the highest seroprevalence estimates. Having a pet in the home (odds ratio [OR], 1.19 [95% CI, 1.01-1.40]) and consuming liver or other organ meats more than once per month (OR, 1.38 [95% CI, 1.01-1.88]) were significantly associated with increased odds of HEV seropositivity. Conclusions. Exposure to HEV is common in the US population, although hepatitis E is rarely reported. Having pets and consuming organ meats may play a role in HEV transmission in the United States, but other mechanisms of transmission may also exist. HEV may be considered a possible etiologic agent of acute and chronic hepatitis in US patients reporting no travel history. [ABSTRACT FROM AUTHOR]