HEPATITIS C

Wisconsin Division of Public Health Disease Surveillance Manual (EpiNet, May, 2005)

I. IDENTIFICATION

A. CLINICAL DESCRIPTION: Symptoms of HCV infection may include anorexia, fatigue, abdominal pain, nausea, dark urine and jaundice. However, 80% persons who acquire HCV-infection have no signs or symptoms. Among persons who acquire HCV infection, 15-45% resolve the infection and 55-85% remain chronically infected.

B. REPORTING CRITERIA: Report all cases of HCV infection, as defined below in I.D. Wisconsin Case Definition section and II.B.3. Hepatitis C Reporting Algorithm.

C. LABORATORY CRITERIA FOR CONFIRMATION:

• Anti-HCV positive (repeat reactive) by enzyme immunoassay (EIA) with a high (≥ 3.8) signal to cut off (s/co) ratio or by chemiluminescence immunoassay (CIA) with a high ( >8.0) s/co ratio; OR

• Anti-HCV positive by recombinant immunoblot assay (RIBA); OR

• HCV RNA positive by reverse transcriptase (RT) polymerase chain reaction (PCR); OR

• Detectable viral load (e.g. HCV bDNA); OR

• Identified HCV genotype.

D. WISCONSIN CASE DEFINITION

Acute Hepatitis C

• Acute illness with discrete onset of symptoms; or a documented anti-HCV seroconversion (from negative to positive); AND

• Serum alanine aminotransferase levels (ALT) >7 times the upper limit of normal; AND

• IgM anti-HAV negative; AND

• IgM anti-HBc negative (if done) or HBsAg negative; AND

• A positive anti-HCV EIA with high s/co ratio or by chemiluminescence immunoassay (CIA) with a high ( >8.0) s/co ratio; or a positive supplemental antibody assay, e.g. RIBA or a positive confirmatory test that detects HCV RNA, e.g., PCR.

Confirmed Hepatitis C

• Anti-HCV positive (repeat reactive) by EIA test result with a high s/co (≥ 3.8) ratio or by chemiluminescence immunoassay (CIA) with a high ( >8.0) s/co ratio; OR

• Anti-HCV positive by RIBA; OR

• HCV RNA positive by PCR; OR

• Detectable viral load (e.g. HCV bDNA); OR

• Identified HCV genotype.

Possible Hepatitis C

• Anti-HCV positive (repeat reactive) by EIA without verification by a more specific assay (e.g. RIBA for anti-HCV or RT-PCR for HCV RNA).

II. ACTIONS REQUIRED/PREVENTION MEASURES

A. WISCONSIN DISEASE SURVEILLANCE CATEGORY II: REPORT TO THE LOCAL HEALTH DEPARTMENT within 72 hours of the identification of a case or suspected case. Public health intervention is expected.

B. EPIDEMIOLOGY REPORTS REQUESTED:

1. Acute and Communicable Disease Report (4151).
2. CDC –Viral Hepatitis Case Report for acute cases only. It is only necessary to complete the demographic section and the section on acute hepatitis C. Viral_Hepatitis_Case_Report
3. Hepatitis C Reporting Algorithm

Algorithm Key

EIA: Enzyme immunoassay

RIBA: Recombinant immunoassay

PCR: Polymerase chain reaction

Ind : Indeterminant

Neg: Negative

Pos: Positive

C. PUBLIC HEALTH INTERVENTIONS

• Advise client on measures to protect the liver from further harm, e.g. by avoiding the use of alcohol and obtaining hepatitis A and hepatitis B vaccine.
• Educate client on how to protect others from exposure to HCV.
• Client referral (self-referral) is used for contacts of HCV cases. Encourage clients to recommend HCV counseling and testing to their needle sharing and sexual partners. HCV counseling and testing services may accessed through primary health care providers, local health departments, AIDS Service Organizations, or STD clinics that offer HCV testing.
• Testing household contacts is not necessary unless they have had an identified blood exposure to the patient.
• An infant whose mother has HCV infection should be tested for anti-HCV no sooner than 12 months of age. If earlier diagnosis is desired, the infant may be tested for HCV RNA (PCR) at 1-2 months for age. An infected mother may breastfeed unless nipples are cracked or bleeding.
• Refer client to a medical provider for medical evaluation to assess liver function and need for treatment.

III. CONTACTS FOR CONSULTATION

1. DPH REGIONAL STAFF: See EpiNet Introduction: “REGIONAL OFFICE CONTACTS”
2. BCD/AIDS/HIV PROGRAM/HEPATITIS PROGRAM: (608) 266-5819
3. WSLH/HEPATITIS SEROLOGY: (608) 262‑2302

IV. RELATED REFERENCES

1. Centers for Disease Control and Prevention. Recommendations for prevention and control of hepatitis C virus (HCV) infection and HCV-related chronic disease. MMWR 1998; 47(No. RR. 19):1-39.
2. Centers for Disease Control and Prevention. Guidelines for laboratory testing and result reporting of antibody to hepatitis C virus. MMWR 2003;52(No. RR-3):1-15.
3. DHFS Hepatitis C Program Web site: http://dhfs.wisconsin.gov/communicable/hepatitis/

V. DISEASE TRENDS

 

Reported Cases of Hepatitis C, Wisconsin , 1997-2004