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Learn about the overview of Hepatitis C, the case definitions for acute and chronic infections, and guidelines for case investigation. Discover the national statistics on Hepatitis C infections and the risk factors for transmission.
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Communicable Disease and Immunization Division Bloodborne Infections and STD Epidemiology Section -HIV/AIDS Surveillance -HIV Behavioral Surveillance -HIV Clinical Monitoring Surveillance -HCV Surveillance and Epidemiology -STD Epidemiology Garry Goza, MS Section Manager 517-335-8165 Gozag@Michigan.gov
Objectives • Hepatitis C Overview • Acute and Chronic Hepatitis C Case Definitions • Guidelines for Hepatitis C Case Investigation • Risk Factors for Infection
National Statistics • Number of new infections per year has declined from an average of 240,000 in the 1980s to about 25,000 in 2001. • Most infections are due to illegal injection drug use. • Estimated 3.9 million (1.8%) Americans have been infected with HCV, of whom 2.7 million are chronically infected. • Translates to roughly 180,000 infections in MI
Viral Hepatitis - Overview Type of Hepatitis A B C D E Source of feces blood/ blood/ blood/ feces virus blood-derived blood-derived blood-derived body fluids body fluids body fluids Route of fecal-oral percutaneous percutaneous percutaneous fecal-oral transmission permucosal permucosal permucosal Chronic no yes yes yes no infection Prevention pre/post- pre/post- blood donor pre/post- ensure safe exposure exposure screening; exposure drinking immunization immunization risk behavior immunization; water modification risk behavior modification
Acute Viral Hepatitis by Type, United States, 1982-1993 34% 47% 16% Hepatitis A Hepatitis B Hepatitis C 3% Hepatitis Non-ABC Source: CDC Sentinel Counties Study on Viral Hepatitis
Case definition - acute HCV infection Clinical criteria for diagnosis: An acute illness with: a) Discrete onset of symptoms and b) Jaundice or elevated serum aminotransferase levels Laboratory criteria for diagnosis: a) Serum alanine aminotransferase (ALT) levels greater than 7 x the upper limit of normal, and b) IgM anti-HAV negative, and c) IgM anti-HBc negative (if done) or HBsAg negative, and d) Antibody to hepatitis C virus (anti-HCV) positive, confirmed by an additional more specific assay such as PCR or RIBA. A confirmed case meets the clinical case definition and the laboratory criteria.
Case definition for chronic hepatitis C infection Criteria for reporting: Antibody to hepatitis C virus (anti-HCV) positive, verified by an additional more specific assay such as PCR or RIBA. No evidence of an acute illness.
Guidelines for Hep C Case Investigation • With the understanding that not all local health departments have the capacity to invest a great deal of time in hepatitis C case investigation, MDCH has drafted guidelines to assist in prioritizing the components of case investigation.
Minimal time commitment… • Verify diagnosis. Verify that an individual with a positive EIA has been confirmed as hepatitis C positive with a supplemental assay (RIBA or PCR). • In populations with low hepatitis C prevalence, false positive EIA tests are frequent. Supplemental testing is necessary to rule out false positive tests.
Minimal time commitment… • Report the case (even if you do not know whether it is chronic or acute). If you do not have time for further case investigation, report “new” cases as chronic hepatitis C. “New” cases are those that have not been previously reported in your county as either acute or chronic. • Surveillance is important! In order to initiate new programs and improve existing programs for those infected with hepatitis C, we first need to improve surveillance and determine the disease burden. This will help us in directing future programs to those who are most in need.
A little more time consuming… • Verify diagnosis. • Assess clinical features. Determine ALT levels to establish if the case is acute (ALT greater than 7xULN) or chronic (ALT less than 7xULN). • 97% of patients with acute hepatitis C have ALT levels greater than 7xULN. Only 3% of chronically infected individuals have such levels. The use of ALT levels greater than 7xULN makes the case definition specific for acute disease. • Report the case as acute or chronic depending on laboratory and clinical findings.
Leave no stone unturned… Verify diagnosis. Assess clinical features.Assess risk factors for infection.
Risk factors for infection • In order to determine the most important modes of transmission for hepatitis C in Michigan, we need to collect complete risk factor information from infected individuals. • This information will allow us to tailor education and prevention programs to your county based on risk factors that are prevalent in your community.
Sources of Infection forPersons With Hepatitis C Injecting drug use 60% Sexual 15% Transfusion 10% (before screening) Occupational 4% Other 1%* Unknown 10% * Nosocomial; iatrogenic; perinatal Source: Centers for Disease Control and Prevention
Reported Cases of Acute Hepatitis C by Selected Risk Factors, United States, 1982-2001* Injecting drug use Sexual Health related work Transfusion * 1982-1990 based on non-A, non-B hepatitis
Injecting Drug Use and HCV Transmission • Highly efficient • Contamination of drug paraphernalia, not just needles and syringes • Rapidly acquired after initiation • 30% prevalence after 3 years • >50% after 5 years • Four times more common than HIV
Routine HCV Testing of Uncertain Need Notconfirmed as risk factor/prevalence low/unknown • Recipients of transplanted tissue • Intranasal cocaine or other non-injecting illegal drug users • History of tattooing, body piercing • History of STDs or multiple sex partners • Long-term steady sex partners of HCV-positive persons Confirmed risk factor but prevalence of infection low
HCV Counseling Persons Using Illegal Drugs • Provide risk reduction counseling, education • Stop using and injecting • Refer to substance abuse treatment program • If continuing to inject • Never reuse or share syringes, needles, or drug preparation equipment • Vaccinate against hepatitis B and hepatitis A • Refer to community-based risk reduction programs
CDC's Position on Tattooing and HCV Infection • Although some studies have found an association between tattooing and HCV infection in very selected populations, it is not known if these results can be generalized to the whole population. • Any percutaneous exposure has the potential for transferring infectious blood and potentially transmitting bloodborne pathogens (e.g., HBV, HCV, or HIV); however, no data exist in the United States indicating that persons with exposures to tattooing alone are at increased risk for HCV infection.
CDC's Position on Tattooing and HCV Infection Continued • For example, during the past 20 years, less than 1% of persons with newly acquired hepatitis C reported to CDC's sentinel surveillance system gave a history of being tattooed. • Further studies are needed to determine if these types of exposures, and the settings in which they occur, are risk factors for HCV infection in the United States. CDC is currently conducting a large study to evaluate tattooing as a potential risk.
Hepatitis C Legislation • Senate filed Hep C Epidemic Control and Prevention Act-May, 2003 • Establishes comprehensive program for HCV public awareness campaigns, screening, counseling, early detection, professional education and research-administered by HHS • First federal response to the Hep C epidemic
Thank you Questions??
Follow-up Slides For potential Questions
Posttransfusion Hepatitis C All volunteer donors HBsAg Donor Screening for HIV Risk Factors Anti-HIV ALT/Anti-HBc Anti-HCV Improved HCV Tests Adapted from HJ Alter and Tobler and Busch, Clin Chem 1997
Perinatal Transmission of HCV • Transmission only from women HCV-RNA positive at delivery • Average rate of infection 6% • Higher (17%) if woman co-infected with HIV • Role of viral titer unclear • No association with • Delivery method • Breastfeeding • Infected infants do well • Severe hepatitis is rare
HCV Counseling Mother-to-Infant Transmission of HCV • Postexposure prophylaxis not available • No need to avoid pregnancy or breastfeeding • Consider bottle feeding if nipples cracked/bleeding • No need to determine mode of delivery based on HCV infection status • Test infants born to HCV-positive women • >15-18 months old • Consider testing any children born since woman became infected • Evaluate infected children for CLD
Sexual Transmission of HCV • Case-control, cross sectional studies • Infected partner, multiple partners, early sex, non-use of condoms, other STDs, sex with trauma, BUT • MSM no higher risk than heterosexuals • Partner studies • Low prevalence (1.5%) among long-term partners • infections might be due to common percutaneous exposures (e.g., drug use), BUT • Male to female transmission more efficient • more indicative of sexual transmission
Sexual Transmission of HCV • Occurs, but efficiency is low • Rare between long-term steady partners • Factors that facilitate transmission between partners unknown (e.g., viral titer) • Accounts for 15-20% of acute and chronic infections in the United States • Sex is a common behavior • Large chronic reservoir provides multiple opportunities for exposure to potentially infectious partners
HCV Counseling Sexual Transmission of HCV Persons with One Long-Term Steady Sex Partner • Do not need to change their sexual practices • Should discuss with their partner • Risk (low but not absent) of sexual transmission • Counseling and testing of partner should be individualized • May provide couple with reassurance • Some couples might decide to use barrier precautions to lower limited risk further
HCV Counseling Sexual Transmission of HCV Persons with High-Risk Sexual Behaviors • At risk for sexually transmitted diseases, e.g., HIV, HBV, gonorrhea, chlamydia, etc. • Reduce risk • Limit number of partners • Use latex condoms • Get vaccinated against hepatitis B • MSMs also get vaccinated against hepatitis A
HCV Counseling Other Transmission Issues • HCV not spread by kissing, hugging, sneezing, coughing, food or water, sharing eating utensils or drinking glasses, or casual contact • Do not exclude from work, school, play, child-care or other settings based on HCV infection status
Occupational Transmission of HCV • Inefficient by occupational exposures • Average incidence 1.8% following needle stick from HCV-positive source • Associated with hollow-bore needles • Case reports of transmission from blood splash to eye; one from exposure to non-intact skin • Prevalence 1-2% among health care workers • Lower than adults in the general population • 10 times lower than for HBV infection
HCV Related to Health CareProcedures United States • Recognized primarily in context of outbreaks • Chronic hemodialysis • Hospital inpatient setting • Private practice setting • Home therapy • Unsafe injection practices • Reuse of syringes and needles • Contaminated multiple dose medication vials
HCW to Patient Transmission of HCV • Rare • In U.S., none related to performing invasive procedures • Most appear related to HCW substance abuse • Reuse of needles or sharing narcotics used for self-injection • No restrictions routinely recommended for HCV-infected HCWs
Household Transmission of HCV • Rare but not absent • Could occur through percutaneous/mucosal exposures to blood • Contaminated equipment used for home therapies • IV therapy, injections • Theoretically through sharing of contaminated personal articles (razors, toothbrushes)