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    1. Chlamydial Infections

      Chlamydial Infections

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Screening for Chlamydial Infection
      7. Treatment of Adolescents and Adults
      8. Management of Sex Partners
      9. Treatment of Neonates and Children
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    2. Gonococcal Infections

      Gonococcal Infections

      1. Introduction
      2. Epidemiology in the United States
      3. Gonococcal Antimicrobial Susceptibility
      4. Microbiology, Pathogenesis, and Transmission
      5. Clinical Manifestations
      6. Laboratory Diagnosis
      7. Screening for Gonococcal Infection
      8. Treatment
      9. Management of Sex Partners
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    3. Syphilis

      Syphilis

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnostic Tests
      6. Screening for Syphilis
      7. Treatment
      8. Post-Treatment Follow Up
      9. Management of Sex Partners
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    4. Genital Herpes

      Genital Herpes

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Screening for HSV-2 Infection
      7. Treatment
      8. Genital HSV in Pregnancy and Neonatal Herpes
      9. Prevention
      10. Patient Counseling and Education
      11. Summary Points
    5. Human Papillomavirus Infection

      Human Papillomavirus Infection

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Diagnosis and Screening Tests
      6. Screening Recommendations for HPV-Related Cancers
      7. Treatment of Anogenital Warts
      8. Prevention of HPV Infection
      9. Counseling and Education
      10. Summary Points
    6. Pelvic Inflammatory Disease

      Pelvic Inflammatory Disease

      1. Introduction
      2. Epidemiology
      3. Microbiology and Pathogenesis
      4. Clinical Manifestations
      5. Diagnosis
      6. Treatment
      7. Management of Sex Partners
      8. Counseling and Education
      9. Summary Points
    7. Vaginitis

      Vaginitis

      1. Introduction
      2. Diagnostic Approach for Vaginitis
      3. Bacterial Vaginosis
      4. Trichomoniasis
      5. Vulvovaginal Candidiasis
      6. Summary Points
    8. Mpox

      Mpox

      1. Introduction
      2. Epidemiology
      3. Virology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Treatment
      7. Infection Control in Health Care Settings
      8. Prevention of Mpox Infection
      9. Counseling and Education
      10. Summary Points
    9. Mycoplasma genitalium

      Mycoplasma genitalium

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Antimicrobial Susceptibility in Mycoplasma genitalium
      5. Clinical Manifestations
      6. Laboratory Diagnostic Tests and Resistance Assays
      7. Diagnostic Testing and Screening Guidelines
      8. Treatment of Mycoplasma genitalium Infection
      9. Counseling and Education
      10. Summary Points
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    1. Chlamydial Infections

      Chlamydial Infections

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Screening for Chlamydial Infection
      7. Treatment of Adolescents and Adults
      8. Management of Sex Partners
      9. Treatment of Neonates and Children
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    2. Gonococcal Infections

      Gonococcal Infections

      1. Introduction
      2. Epidemiology in the United States
      3. Gonococcal Antimicrobial Susceptibility
      4. Microbiology, Pathogenesis, and Transmission
      5. Clinical Manifestations
      6. Laboratory Diagnosis
      7. Screening for Gonococcal Infection
      8. Treatment
      9. Management of Sex Partners
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    3. Syphilis

      Syphilis

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnostic Tests
      6. Screening for Syphilis
      7. Treatment
      8. Post-Treatment Follow Up
      9. Management of Sex Partners
      10. Counseling and Education
      11. Prevention
      12. Summary Points
    4. Genital Herpes

      Genital Herpes

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Screening for HSV-2 Infection
      7. Treatment
      8. Genital HSV in Pregnancy and Neonatal Herpes
      9. Prevention
      10. Patient Counseling and Education
      11. Summary Points
    5. Human Papillomavirus Infection

      Human Papillomavirus Infection

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Diagnosis and Screening Tests
      6. Screening Recommendations for HPV-Related Cancers
      7. Treatment of Anogenital Warts
      8. Prevention of HPV Infection
      9. Counseling and Education
      10. Summary Points
    6. Pelvic Inflammatory Disease

      Pelvic Inflammatory Disease

      1. Introduction
      2. Epidemiology
      3. Microbiology and Pathogenesis
      4. Clinical Manifestations
      5. Diagnosis
      6. Treatment
      7. Management of Sex Partners
      8. Counseling and Education
      9. Summary Points
    7. Vaginitis

      Vaginitis

      1. Introduction
      2. Diagnostic Approach for Vaginitis
      3. Bacterial Vaginosis
      4. Trichomoniasis
      5. Vulvovaginal Candidiasis
      6. Summary Points
    8. Mpox

      Mpox

      1. Introduction
      2. Epidemiology
      3. Virology, Pathogenesis, and Transmission
      4. Clinical Manifestations
      5. Laboratory Diagnosis
      6. Treatment
      7. Infection Control in Health Care Settings
      8. Prevention of Mpox Infection
      9. Counseling and Education
      10. Summary Points
    9. Mycoplasma genitalium

      Mycoplasma genitalium

      1. Introduction
      2. Epidemiology in the United States
      3. Microbiology, Pathogenesis, and Transmission
      4. Antimicrobial Susceptibility in Mycoplasma genitalium
      5. Clinical Manifestations
      6. Laboratory Diagnostic Tests and Resistance Assays
      7. Diagnostic Testing and Screening Guidelines
      8. Treatment of Mycoplasma genitalium Infection
      9. Counseling and Education
      10. Summary Points
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  1. Quick Reference
  2. Hepatitis A
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    Anogenital Warts
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            Chancroid
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            Chlamydial Infections
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                  Granuloma Inguinale (Donovanosis)
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                                HPV-Associated Cancers and Precancers
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                                      Mycoplasma genitalium
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                                        Pediculosis Pubis
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                                              Proctitis, Proctocolitis, and Enteritis
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                                                  Sexual Assault and Abuse and STIs
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                                                      Trichomoniasis
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                                                        Urethritis
                                                        Activities
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                                                        Lesson 10. Hepatitis A

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                                                        Table of Contents
                                                        • Hepatitis A
                                                        • References
                                                        • Tables
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                                                        References

                                                        • Advisory Committee on Immunization Practices (ACIP), Fiore AE, Wasley A, Bell BP. Prevention of hepatitis A through active or passive immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2006;55:1-23.
                                                          [PubMed Abstract] -
                                                        • Advisory Committee on Immunization Practices. Supplementary text 1. Provider Guidance on Risk Assessment and Clinical Decision-making for Hepatitis A Postexposure Prophylaxis. Supplements: Update: Recommendations of the Advisory Committee on Immunization Practices for use of Hepatitis A vaccine for post-exposure prophylaxis and for international travel. November 2, 2018
                                                          [CDC] -
                                                        • Bell BP, Shapiro CN, Alter MJ, et al. The diverse patterns of hepatitis A epidemiology in the United States-implications for vaccination strategies. J Infect Dis. 1998;178:1579-84.
                                                          [PubMed Abstract] -
                                                        • Bialek SR, Barry V, Bell BP, et al. Seroprevalence and correlates of hepatitis a among HIV-negative American men who have sex with men. Sex Health. 2011;8:343-8.
                                                          [PubMed Abstract] -
                                                        • Bohm SR, Berger KW, Hackert PB, et al. Hepatitis A outbreak among adults with developmental disabilities in group homes--Michigan, 2013. MMWR Morb Mortal Wkly Rep. 2015;64:148-52.
                                                          [PubMed Abstract] -
                                                        • Bower WA, Nainan OV, Han X, Margolis HS. Duration of viremia in hepatitis A virus infection. J Infect Dis. 2000;182:12-7.
                                                          [PubMed Abstract] -
                                                        • Brennan J, Moore K, Sizemore L, et al. Notes from the Field: Acute Hepatitis A Virus Infection Among Previously Vaccinated Persons with HIV Infection - Tennessee, 2018. MMWR Morb Mortal Wkly Rep. 2019;68:328-329.
                                                          [PubMed Abstract] -
                                                        • Brundage SC, Fitzpatrick AN. Hepatitis A. Am Fam Physician. 2006;73:2162-8.
                                                          [PubMed Abstract] -
                                                        • Centers for Disease Control and Prevention (CDC). Hepatitis A Surveillance 2022. April 2024.
                                                          [CDC] -
                                                        • Cuthbert JA. Hepatitis A: old and new. Clin Microbiol Rev. 2001;14:38-58.
                                                          [PubMed Abstract] -
                                                        • Doshani M, Weng M, Moore KL, Romero JR, Nelson NP. Recommendations of the Advisory Committee on Immunization Practices for Use of Hepatitis A Vaccine for Persons Experiencing Homelessness. MMWR Morb Mortal Wkly Rep. 2019;68:153-156.
                                                          [PubMed Abstract] -
                                                        • Foster M, Ramachandran S, Myatt K, et al. Hepatitis A Virus Outbreaks Associated with Drug Use and Homelessness - California, Kentucky, Michigan, and Utah, 2017. MMWR Morb Mortal Wkly Rep. 2018;67:1208-1210.
                                                          [PubMed Abstract] -
                                                        • Foster MA, Hofmeister MG, Kupronis BA, et al. Increase in Hepatitis A Virus Infections - United States, 2013-2018. MMWR Morb Mortal Wkly Rep. 2019;68:413-5.
                                                          [PubMed Abstract] -
                                                        • Girardi E, Scognamiglio P, Sciarrone MR, et al. High HIV prevalence in male patients with acute hepatitis A in the Rome metropolitan area, Italy 2002-2008. J Hepatol. 2011;54:1102-6.
                                                          [PubMed Abstract] -
                                                        • Klevens RM, Kruszon-Moran D, Wasley A, et al. Seroprevalence of hepatitis A virus antibodies in the U.S.: results from the National Health and Nutrition Examination Survey. Public Health Rep. 2011;126:522-32.
                                                          [PubMed Abstract] -
                                                        • Latash J, Dorsinville M, Del Rosso P, et al. Notes from the Field: Increase in Reported Hepatitis A Infections Among Men Who Have Sex with Men - New York City, January-August 2017. MMWR Morb Mortal Wkly Rep. 2017;66:999-1000.
                                                          [PubMed Abstract] -
                                                        • Link-Gelles R, Hofmeister MG, Nelson NP. Use of hepatitis A vaccine for post-exposure prophylaxis in individuals over 40 years of age: A systematic review of published studies and recommendations for vaccine use. Vaccine. 2018;36:2745-50.
                                                          [PubMed Abstract] -
                                                        • Litt IF, Cohen MI. Perihepatitis associated with salpingitis in adolescents. JAMA. 1978;240:1253-4.
                                                          [PubMed Abstract] -
                                                        • Lu PJ, Byrd KK, Murphy TV. Hepatitis A vaccination coverage among adults 18-49 years traveling to a country of high or intermediate endemicity, United States. Vaccine. 2013;31:2348-57.
                                                          [PubMed Abstract] -
                                                        • Ly KN, Klevens RM. Trends in disease and complications of hepatitis A virus infection in the United States, 1999-2011: a new concern for adults. J Infect Dis. 2015;212:176-82.
                                                          [PubMed Abstract] -
                                                        • McKnight KL, Lemon SM. Hepatitis A Virus Genome Organization and Replication Strategy. Cold Spring Harb Perspect Med. 2018;8(12). pii: a033480.
                                                          [PubMed Abstract] -
                                                        • Nainan OV, Xia G, Vaughan G, Margolis HS. Diagnosis of hepatitis a virus infection: a molecular approach. Clin Microbiol Rev. 2006;19:63-79.
                                                          [PubMed Abstract] -
                                                        • Nelson NP, Link-Gelles R, Hofmeister MG, et al. Update: Recommendations of the Advisory Committee on Immunization Practices for Use of Hepatitis A Vaccine for Postexposure Prophylaxis and for Preexposure Prophylaxis for International Travel. MMWR Morb Mortal Wkly Rep. 2018;67:1216-1220.
                                                          [PubMed Abstract] -
                                                        • Nelson NP, Weng MK, Hofmeister MG, et al. Prevention of Hepatitis A Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices, 2020. MMWR Recomm Rep. 2020;69:1-38.
                                                          [PubMed Abstract] -
                                                        • Nelson NP. Updated Dosing Instructions for Immune Globulin (Human) GamaSTAN S/D for Hepatitis A Virus Prophylaxis. MMWR Morb Mortal Wkly Rep. 2017;66:959-960.
                                                          [PubMed Abstract] -
                                                        • Ott JJ, Irving G, Wiersma ST. Long-term protective effects of hepatitis A vaccines. A systematic review. Vaccine. 2012;31:3-11.
                                                          [PubMed Abstract] -
                                                        • Raczniak GA, Bulkow LR, Bruce MG, et al. Long-term immunogenicity of hepatitis A virus vaccine in Alaska 17 years after initial childhood series. J Infect Dis. 2013;207:493-6.
                                                          [PubMed Abstract] -
                                                        • Raczniak GA, Thomas TK, Bulkow LR, et al. Duration of protection against hepatitis A for the current two-dose vaccine compared to a three-dose vaccine schedule in children. Vaccine. 2013;31:2152-5.
                                                          [PubMed Abstract] -
                                                        • Regan DG, Wood JG, Benevent C, et al. Estimating the critical immunity threshold for preventing hepatitis A outbreaks in men who have sex with men. Epidemiol Infect. 2016;144:1528-37.
                                                          [PubMed Abstract] -
                                                        • Sharapov UM, Bulkow LR, Negus SE, et al. Persistence of hepatitis A vaccine induced seropositivity in infants and young children by maternal antibody status: 10-year follow-up. Hepatology. 2012;56:516-22.
                                                          [PubMed Abstract] -
                                                        • Storch GA, Bodicky C, Parker M, Blecka LJ, Aach RD. Use of conventional and IgM-specific radioimmunoassays for anti-hepatitis A antibody in an outbreak of hepatitis A. Am J Med. 1982;73:663-8.
                                                          [PubMed Abstract] -
                                                        • Tong MJ, el-Farra NS, Grew MI. Clinical manifestations of hepatitis A: recent experience in a community teaching hospital. J Infect Dis. 1995;171 Suppl 1:S15-8.
                                                          [PubMed Abstract] -
                                                        • Van Herck K, Jacquet JM, Van Damme P. Antibody persistence and immune memory in healthy adults following vaccination with a two-dose inactivated hepatitis A vaccine: long-term follow-up at 15 years. J Med Virol. 2011;83:1885-91.
                                                          [PubMed Abstract] -
                                                        • Victor JC, Monto AS, Surdina TY, et al. Hepatitis A vaccine versus immune globulin for postexposure prophylaxis. N Engl J Med. 2007;357:1685-94.
                                                          [PubMed Abstract] -
                                                        • Wallace MR, Brandt CJ, Earhart KC, et al. Safety and immunogenicity of an inactivated hepatitis A vaccine among HIV-infected subjects. Clin Infect Dis. 2004;39:1207-13.
                                                          [PubMed Abstract] -
                                                        • Winokur PL, Stapleton JT. Immunoglobulin prophylaxis for hepatitis A. Clin Infect Dis. 1992;14:580-6.
                                                          [PubMed Abstract] -
                                                        • Workowski KA, Bachmann LH, Chan PA, et al. Sexually transmitted infections treatment guidelines, 2021. Viral hepatitis infections: hepatitis A virus (HAV) infection. MMWR Recomm Rep. 2021;70(No. RR-4):1-187.
                                                          [2021 STI Treatment Guidelines] -

                                                        Tables

                                                        Table 1.

                                                        Recommended Regimens: Dose and Schedule for Hepatitis A Vaccines

                                                        Vaccine Age Group Dosage Route Schedule Booster
                                                        Havrix 1-18 years
                                                        ≥19 years
                                                        0.5 mL (720 ELU)
                                                        1.0 mL (1,440 ELU)
                                                        IM
                                                        IM
                                                        0, 6-12 months
                                                        0, 6-12 months
                                                        None
                                                        None
                                                        Vaqta 1-18 years
                                                        ≥19 years
                                                        0.5 mL (25 U)
                                                        1 ml (50 U)
                                                        IM
                                                        IM
                                                        0, 6-18 months
                                                        0, 6-18 months
                                                        None
                                                        None
                                                        Twinrix ≥18 years (primary)
                                                        ≥18 years (accelerated)
                                                        1 mL (720 ELU HAV + 20 µg HBsAg)
                                                        1 mL (720 ELU HAV + 20 µg HBsAg)
                                                        IM
                                                        IM
                                                        0, 1, 6 months
                                                        0, 7, 21-30 days
                                                        None
                                                        12 months
                                                        Abbreviations: ELU = ELISA units of inactivated HAV: HBV= hepatitis B Virus; HbsAg = hepatitis B surface antigen
                                                        Source:
                                                        • Nelson NP, Link-Gelles R, Hofmeister MG, et al. Update: Recommendations of the Advisory Committee on Immunization Practices for Use of Hepatitis A Vaccine for Postexposure Prophylaxis and for Preexposure Prophylaxis for International Travel. MMWR Morb Mortal Wkly Rep. 2018;67:1216-1220. [PubMed Abstract]
                                                        Table 2.

                                                        Recommendations for Postexposure Prophylaxis Following Exposure to Hepatitis A Virus (HAV)

                                                        Indication/Age Group Risk Category/Health Status HAV Vaccine Immune Globulin
                                                        <1 year Healthy No 0.1 mL/kg body weight*
                                                        1-40 years Healthy 1 dose^ None
                                                        >40 years Healthy 1 dose^ 0.1 mL/kg body weight§
                                                        ≥1 Year Immunocompromised or chronic liver Disease 1 dose^ 0.1 mL/kg body weight#
                                                        ≥1 Year Vaccine Contraindication** No 0.1 mL/kg body weight*

                                                        *Measles, mumps, and rubella vaccine should not be administered for at least 3 months after receipt of Immune globulin
                                                        ^A second dose is not required for postexposure prophylaxis; however, for long-term immunity, the hepatitis A vaccination series should be completed with a second dose at least 6 months after the first dose.
                                                        §The provider’s risk assessment should determine the need for immune globulin administration. If the provider’s risk assessment determines that both vaccine and immune globulin are warranted, HepA vaccine and immune globulin should be administered simultaneously at different anatomic sites.
                                                        #Vaccine and immune globulin should be administered simultaneously at different anatomic sites.
                                                        **Life-threatening allergic reaction to a previous dose of hepatitis A vaccine, or allergy to any vaccine component.

                                                        Source:
                                                        • Nelson NP, Link-Gelles R, Hofmeister MG, et al. Update: Recommendations of the Advisory Committee on Immunization Practices for Use of Hepatitis A Vaccine for Postexposure Prophylaxis and for Preexposure Prophylaxis for International Travel. MMWR Morb Mortal Wkly Rep. 2018;67:1216-1220. [PubMed Abstract]

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