Trends in Herpes Simples Virus Type 2 infection in the United States Fujie Xu, Geraldine McQuillan, Benny Kottiri, Maya Sternberg, Francis Lee, André Nahmias, Lauri Markowitz Centers for Disease Control and Prevention (CDC) Emory University
Background HSV-2 is the cause of most genital herpes HSV-2 increases the risk for HIV acquisition and transmission HSV-2 seroprevalence is a marker of sexual risk behaviors In adolescents and young adults, HSV-2 seroprevalence is a measure of more recent risky sexual behaviors
Data Source NHANES—National Health And Nutrition Examination Survey A series of nationally representative surveys of non-institutionalized US population Survey staff travel across the nation to conduct interviews and health examinations
Study Objectives Describe trends of HSV-2 seroprevalence in the US between two NHANES surveys: NHANES III: NHANES The mid-point interval between this two surveys was 8.5 years
Statistical Methods Age-adjustment –2000 US Census as the standard population Weights –Accounting for oversampling and non- response SUDAAN software –Accounting for multi-stage sampling design
HSV-2 Serology Type-specific immunodot assay –Glycoprotein of gG2 as antigen The same assay and the same laboratory was used for both surveys
Results Surveys NHANES III ( ) NHANES Examination rate 76%78% Sample size Total Total By age (years) By age (years)
Changes in HSV-2 Seroprevalence By Age Group Variables NHANES III ( ) % (95% CI) % (95% CI)NHANES % (95% CI) Percentagechange Total Age (yrs) (19.4, 23.3) 5.8 (4.4, 7.5 ) 17.2 (14.9, 19.8) 27.8 (24.6, 31.4) 26.3 (23.0, 30.1) 17.6 (15.4, 20.0) 1.5 (0.9, 2.7) 8.9 (7.2, 11.1) 25.4 (21.6, 29.9) 26.4 (21.4, 32.5) -17%†-74%‡-48%‡-9%-0% CI, confidence interval. † p<0.05; ‡ p<0.001
Changes in HSV-2 Seroprevalence By Age Group
Changes in HSV-2 Seroprevalence Variables NHANES III ( ) % (95% CI) % (95% CI)NHANES % (95% CI) Percentagechange Sex Males Males Females FemalesRace/ethnicity NH whites NH whites NH blacks NH blacks Mex Americans Mex Americans 17.2 (14.8, 19.9) 25.4 (23.5, 27.5) 16.7 (14.6, 19.1) 43.0 (40.9, (20.4, 24.8) 11.2 (9.1, 13.8) 23.5 (20.5, 27.1) 13.5 (10.8, 16.8) 40.3 (36.4, 44.7) 12.1 (9.5, 15.5) -35%†-7%-19%-6%-46%‡ CI, confidence interval. † p<0.05; ‡ p<0.001
Changes in HSV-2 Seroprevalence in year-olds Variables NHANES III ( ) N = 4537 % (95% CI) % (95% CI)NHANES N = 2232 % (95% CI) Percentagechange Sex Males Males Females FemalesRace/ethnicity NH whites NH whites NH blacks NH blacks Mex Americans Mex Americans 9.8 (7.5, 12.9) 16.6 (14.9, 18.6) 11.1 (9.0, 13.9) 24.9 (21.9, 28.2) 11.7 (9.7, 14.1) 4.0 (2.7, 5.9) 8.5 (6.4, 11.2) 3.3 (1.9, 5.4) 21.9 (16.8, 28.5) 6.2 (3.6, 10.8) -59%‡-49%‡-70%†-12%-47%† CI, confidence interval. † p<0.05; ‡ p<0.001
Conclusions HSV-2 seroprevalence decreased significantly between NHANES III and NHANES ‘99-00 The largest decrease occurred in adolescents In adolescents and young adults (14-29 year-olds), significant decreases occurred in all sex and race/ethnicity groups except non-Hispanic blacks
Limitations Limited behavioral data in NHANES –The number of lifetime sex partners –Changes in methods and wordings Changes in US population –Mexican Americans Small sample size of NHANES’99-00
Discussion Is the decrease in HSV-2 infection real? NHANES to be released in May 2004 HSV-2 included in NHANES
Changes in HSV-2 Seroprevalence between NHANES II and NHANES III Fleming DT et al. N Engl J Med 1997; 337:
HSV-2 Seroprevalence in NHANES By Age Group
Discussion (cont) Youth Risk Behavior Surveys ( )* Ever had sex Ever had sex Had four or more partners Had four or more partners Used condoms Used condoms Between 1990 and 2000, teen pregnancy rates in women aged in the US decreased 28%**. * CDC. MMWR 2002; 51: Data from the Alan Guttmacher Institute **Data from the Alan Guttmacher Institute
Teenage Pregnancy Rate in the US, Rate per 1,000 women aged 15-19
Changes in HSV-1 Seroprevalence between the two NHANES Surveys Variables NHANES III ( ) % (95% CI) % (95% CI)NHANES % (95% CI) Percentagechange Total By age (59, 65) 46 (42, 50) 56 (52, 60) 66 (62, 70) 73 (69, 77) 60 (57, 62) 43 (38, 49) 59 (55, 63) 64 (60, 68) 65 (60, 70) -4%-5%5%-2%-11%† CI, confidence interval. † p<0.05
Discussion (cont) An analysis found that about 25% of the decline in teenage pregnancy between 1988 and 1995 was due to decreased sexual activity. * Data from the Alan Guttmacher Institute