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The Public Health Response to Genital Herpes: Where Do We Stand?. H. Hunter Handsfield, M.D. Connie L. Celum, M.D., M.P.H. Lawrence Corey, M.D. Gail Bolan, M.D., M.P.H. Peter A. Leone, M.D., M.P.H. The Public Health Response to Genital Herpes: Where Do We Stand?.
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The Public Health Response to Genital Herpes: Where Do We Stand? H. Hunter Handsfield, M.D. Connie L. Celum, M.D., M.P.H. Lawrence Corey, M.D. Gail Bolan, M.D., M.P.H. Peter A. Leone, M.D., M.P.H.
The Public Health Response to Genital Herpes: Where Do We Stand? • Diagnosis: Test Performance and Practical Issues in Implementation (Handsfield; 20 min) • HIV/HSV-2 Interactions: Implications for Prevention (Celum; 20 min) • Prevention: Effective Strategies Old and New (Corey; 20 min) • A Real-World Model (Straw Man?) for Genital Herpes Clinical Care and Prevention in Public Health Settings (Handsfield; 5 min) • Comment and Critique (Bolan, Leone, Panel; 10 min) • Discussion (Audience and Panel; 30 min)
The Public Health Response to Genital Herpes: Where Do We Stand? Diagnosis of Genital Herpes: Test Performance and Practical Issues in Implementation H. Hunter Handsfield, M.D. University of Washington Public Health - Seattle & King County Seattle, Washington
Public Health Issues in Genital HerpesThe Six Biggies • Preventing sexual transmission of HSV • Relationship of HSV-2 infection to HIV transmission and its prevention • Underdiagnosis of genital ulcer disease • The roles of type-specific serological testing • Under-treatment • Preventing neonatal herpes
Clinical Diagnosis of Genital Ulcer Disease • N = 446; microbiologic or virologic diagnosis made in 220 (49%) • Sensitivity of classical clinical appearance was poor (31-35%) for herpes, syphilis, and chancroid • Specificity was good for syphilis (98%), high PPV • Specificity only 94%for HSV and chancroid, low PPV • Conclusion: Classic chancre reliably indicates syphilis, but is insensitive; otherwise, clinical diagnosis is unreliable lab tests essential DiCarlo RP, Martin DH. CID 1997;25:299-300
Etiology of Genital Ulcer Disease • 516 GUD patients from STD Clinics in 10 of 11 U.S. cities w/ highest syphilis rates • Excluded patients with typical herpes • PCR for HSV, T. pallidum, H. ducreyi HSV 333 (64.5%) Syphilis 64 (12.4%) HSV + Syphilis 13 (2.5%) Chancroid 16 (3.1%) PCR negative 116 (22.4%) Mertz K et al, JID1998;178:1795-8
Diagnosis of Genital Herpes • Test all genital ulcers for HSV • Also test all cases of classical genital herpes • Clinical diagnosis insensitive and nonspecific • Virus type determines clinical prognosis, transmission, and counseling • Virologic tests • PCR is test of choice; increasingly available • Culture: The primary test in most settings • Direct FA: Some don’t provide virus type • Cytology (Tzanck prep): Insensitive, no virus type, little or no use • Serological testing: Use only glycoprotein G (gG) based assays
Type-Specific HSV Serological Tests Antibody to HSV-1 or -2 glycoprotein G (gG-1 or gG-2) • Western blot • The gold standard • Focus Technologies (formerly MRL) HerpeSelectTM HSV-1 and HSV-2 ELISA • Sensitivity for HSV-2 ~90, specificity ~98% • Focus Technologies HerpeSelectTM HSV-1 and HSV-2 Differentiation Immunoblot • Same antigen as ELISA, probably similar performance
Proficiency Testing for HSV-1 and HSV-2 Antibody TestsAmerican College of Clinical Pathologists • HSV-1 positive, HSV-2 negative (Western blot) serum sent to 172 participating laboratories • HSV-1 antibody detected 168 (98%) • HSV-2 reported positive • EIA (N = 153) 73 (48%) • Non-EIA (N = 26) 23 (89%) • gG based EIA (Focus) (N = 44) 0 • Tests to be avoided: Wampole, Zeus, DiaSorin Ashley-Morrow R, Friedrich R: Am J Clin Path December 2003
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Persons at Risk Desire HSV Testing • Leeds, UK, 200 consecutive STD patients: 92% for themselves, 91% for their partners (Fairley & Monteiro, Genitourin Med 1997;73:259-62) • Seattle, Washington, USA, STD clinic patients (Wald et al, unpublished) • Cost-free testing: 756/1477 (51%) • At $15.00: 558/3099 (18%) • Studies also indicate that many persons say they a positive test result would be put to use to protect partners from transmission (Stoner; Douglas; others)
Testing for Genital Herpes • A decision to not even offer serological testing to persons at risk for genital herpes is, at its core, paternalistic: • “I know what is best for you... • ...and I’m not even going to give you the option” • A decision to not offer testing essentially prioritizes provider issues over patient needs and prevention • Counseling uncertainties • Time • Costs
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Positive Predictive ValueSensitivity 90 %, Specificity 98% PrevalencePPVFP Rate • 10% 83% 1 in 6 • 25% 94% 1 in 20 • 50% 98% 1 in 50
PPV of HSV-2 ELISA Based on HSV-1 Serostatus and ELISA Optical Density Index 102 Men HSV-2 pos ELISA Western blot done 44 HSV-1 neg by Western blot 58 HSV-1 pos by Western blot 44 HSV-2 pos by Western blot (PPV=100%) 41 HSV-2 pos by Western blot (PPV=71%) OD Index <3.0 OD Index >3.0 33/34 HSV-2 pos by Western blot (PPV=97%) 8/24 HSV-2 pos by Western blot (PPV=33%)
HSV-2 ELISA Testing Algorithm HSV-2 serology HSV-2 OD Index <3.0 Run HSV-1 serology HSV-2 OD Index >3.0 HSV-1 negative HSV-1 positive HSV-2 indeterminate Repeat testing 3 months or Western Blot HSV-2 true positive
Options for Confirmatory Testing of the Focus HSV-2 ELISA • Western blot • HSV-1/OD index testing algorithm • Focus immunoblot? • Focus ELISA avidity assay? • Commercial confirmatory tests (rumors) • Focus • Others? • Repeat/convalescent testing
A Perspective on Confirmatory Testing • Confirmation of Focus HSV-2 ELISA is an issue only in populations at low or modest risk (e.g., prevalence <25%), not for diagnostic testing (prior probability typically >50%) • Clinical suspicion of herpes • Sex partners of HSV-2-infected persons • Most (all?) populations at risk for HIV • In lower risk settings, follow the OD index/HSV-1 algorithm if/when confirmed in larger studies • “Sell” HSV serological testing as test for diagnosis and for other patently high-risk settings • Screening in other settings will follow naturally as providers gain comfort with high-risk testing
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Costs of HSV Serological Tests Medicaid Reimb $22 $15 $40 Variable • Focus ELISA • HSV-2 • HSV-1 • Focus immunoblot • Western blot Cost $5 $5 $25 $50 Lab Fee* $15# $10# $40 $120-150 * PHSKC Laboratory # HSV-1 stand alone $15, HSV-1 & 2 $25; STD Clinic pays $5 each
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Elements of Herpes Education and Counseling • Natural course of disease • Subclinical shedding • Options to reduce transmission risk • Symptom recognition abstinence • Condoms • Antiviral therapy • Increased risk of HIV conferred by HSV-2 • Neonatal herpes risks and prevention • Minimal pre-test counseling: Counseling should not be a barrier to testing
Barriers to HSV-2 Serological Testing(And to Genital Herpes Prevention in General) • Disbelief that HSV-2 infection matters • Test performance • Cost • Counseling barriers • Benefits vs Risks
Public Health Approaches to Genital Herpes Prevention • Test all genital ulcers for HSV • Liberal use of type-specific serologic tests - Sex partners of infected persons - Suggestive symptoms - Patient request to R/O genital herpes - Selected pregnant women and partners - Persons with or at risk for HIV infection • Assure that patients’ sex partners are evaluated
Public Health Approaches to Genital Herpes Prevention • Counsel infected persons and partners • Subclinical shedding • Symptom recognition • Personal prevention strategies (condoms, abstinence during symptoms) • Consider antiviral therapy to prevent Cesarean section (may help prevent some cases of neonatal herpes) • Antiviral therapy of selected infected persons to prevent transmission
Biomedical Complications of HSV-2 Genital Infection • Localized neuropathic manifestations • Meningitis (isolated, recurrent) • Erythema multiforme, Stevens Johnson syndrome • Perinatal and maternal morbidity • Neonatal herpes • Cesarean section • Nongenital autoinoculation syndromes (conjunctivitis, keratitis, whitlow) • Chronic localized disease in immunodeficient patients (especially HIV/AIDS) • Enhanced HIV transmission
Uses of Type-Specific HSV Serology Definite Indications • Diagnosis of GUD, recurrent Sx, etc • Management of sex partners of persons with herpes • Persons with or at risk for sexual acquisition of HIV Other Uses • Selected (all?) pregnant women and their partners • Patient request • Request to test for herpes • Comprehensive STD evaluation • Do not use routinely to screen all sexually active persons (controversial)
Screening for Genital Herpes • A decision to not even offer serological testing to persons at risk for genital herpes is, at its core, paternalistic: • “I know what is best for you... • ...and I’m not even going to give you the option” • A decision not to offer testing essentially prioritizes provider issues over patient needs and prevention • Counseling uncertainties • Time • Costs
Persons at Risk Desire HSV Testing • Leeds, UK, 200 consecutive STD patients: 92% for themselves, 91% for their partners (Fairley & Monteiro, Genitourin Med 1997;73:259-62) • Seattle, Washington, USA, STD clinic patients (Wald et al, unpublished) • Cost-free testing: 756/1477 (51%) • At $15.00: 558/3099 (18%) • Studies also indicate that many persons say they a positive test result would be put to use to protect partners from transmission (Stoner; Douglas; others)
Psychological Impact of Genital Herpes Diagnosis • Significant impact(Carney et al, Genitourin Med 1994;70:40-5) • Depression, isolation, fear of rejection: 55-82%of patients with initial GH • Less frequent with repeat outbreaks (28-58%) • Or not so significant: No impairment on standard psych testing of patients with RGH (median 6 yr)(Brookes et al, Genitourin Med 1993;69:384-7) • Responds to suppressive treatment(Patel et al, Sex Transm Infect 1999;75:398) • Anecdotal experience reassuring with frequent testing • Public Health - Seattle King Co. STD Clinic • Prenatal patients <5% (Brown et al)
Psychological Impact of Genital Herpes Diagnosis • So, the psychological impact is or isn’t very large; variable results, undoubtedly related to differences between populations and study design • Whatever impact there is appears to be largely transient, likely responsive to counseling, and reduced by antiviral therapy • Thus, either it is not a serious problem... OR • It is a serious problem, making it all the more important to prevent continued transmission - which requires serologic diagnosis