VIRAL HEPATITIS C
mkolar@med.muni.cz EPI; Autumn 2019
Features of Hepatitis C Virus Infection
Incubation period Average 6-7 weeks
Range 2-26 weeks
Acute illness (jaundice) Mild (<20%)
Case fatality rate Low
Chronic infection 60%-85%
Chronic hepatitis 10%-70% (most asx)
Cirrhosis <5%-20%
Mortality from CLD 1%-5%
Age-
related
HEPATITIS C (Hepatitis C virus) – Case definition
Clinical Criteria
 Not relevant for surveillance purposes
Laboratory Criteria
 At least one of the following three:
 — Detection of hepatitis C virus nucleic acid (HCV RNA)
 — Detection of hepatitis C virus core antigen (HCV-core)
 — Hepatitis C virus specific antibody (anti-HCV) response confirmed by a confirmatory
(e.g. immunoblot) antibody test in persons older than 18 months without evidence of
resolved infection)
Epidemiological Criteria NA
Case Classification
 A. Possible case NA
 B. Probable case NA
 C. Confirmed case
 Any person meeting the laboratory criteria
Chronic Hepatitis C
Factors Promoting Progression or Severity
 Increased alcohol intake
 Age > 40 years at time of infection
 HIV co-infection
 Other
– Male gender
– Chronic HBV co-infection
Serologic Pattern of Acute HCV Infection
with Recovery
Symptoms +/Time
after Exposure
Titer anti-HCV
ALT
Normal
0 1 2 3 4 5 6 1 2 3 4
YearsMonths
HCV RNA
Serologic Pattern of Acute HCV Infection with
Progression to Chronic Infection
Symptoms +/Time
after Exposure
Titer anti-HCV
ALT
Normal
0 1 2 3 4 5 6 1 2 3 4
YearsMonths
HCV RNA
Exposures Known to Be Associated With
HCV Infection in the United States
 Injecting drug use
 Transfusion, transplant from infected donor
 Occupational exposure to blood
– Mostly needle sticks
 Iatrogenic (unsafe injections)
 Birth to HCV-infected mother
 Sex with infected partner
– Multiple sex partners
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
Posttransfusion Hepatitis C
0
5
10
15
20
25
30
1965 1970 1975 1980 1985 1990 1995 2000
Year
%ofRecipientsInfected
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
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 Care Procedures
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
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
Sexual Transmission of HCV
 Case-control, cross sectional studies
– Infected partner, multiple partners, early sex, nonuse
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
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)
Other Potential Exposures to Blood
 No or insufficient data showing increased risk
– intranasal cocaine use, tattooing, body piercing,
acupuncture, military service
 No associations in acute case-control or populationbased
studies
 Cross-sectional studies in highly selected groups with
inconsistent results
– Temporal relationship between exposure and infection
usually unknown
– Biologically plausible, but association or causal relationship
not established
Sources of Infection for
Persons With Hepatitis C
Sexual 15%
Other 1%*
Unknown 10%
Injecting drug use 60%
Transfusion 10%
(before screening)
* Nosocomial; iatrogenic; perinatal
Source: Centers for Disease Control and Prevention
Occupational 4%
Reduce or Eliminate Risks for
Acquiring HCV Infection
 Screen and test donors
 Virus inactivation of plasma-derived products
 Risk-reduction counseling and services
– Obtain history of high-risk drug and sex behaviors
– Provide information on minimizing risky behavior,
including referral to other services
– Vaccinate against hepatitis A and/or hepatitis B
 Safe injection and infection control practices
HCV Prevention and Control
MMWR 1998;47 (No. RR-19)
Reduce Risks for Disease Progression
and Further Transmission
 Identify persons at risk for HCV and test to
determine infection status
– Routinely identify at risk persons through history,
record review
 Provide HCV-positive persons
– Medical evaluation and management
– Counseling
• Prevent further liver damage
• Prevent transmission to others
HCV Prevention and Control
MMWR 1998;47 (No. RR-19)
HCV Testing Routinely Recommended
 Ever injected illegal drugs
 Received clotting factors made before 1987
 Received blood/organs before July 1992
 Ever on chronic hemodialysis
 Evidence of liver disease
 Healthcare, emergency, public safety workers after
needle stick/mucosal exposures to HCV-positive blood
 Children born to HCV-positive women
Based on increased risk for infection
Based on need for exposure management
Postexposure Management for HCV
 IG, antivirals not recommended for prophylaxis
 Follow-up after needlesticks, sharps, or mucosal
exposures to HCV-positive blood
– Test source for anti-HCV
– Test worker if source anti-HCV positive
• Anti-HCV and ALT at baseline and 4-6 months later
• For earlier diagnosis, HCV RNA at 4-6 weeks
– Confirm all anti-HCV results with RIBA
 Refer infected worker to specialist for medical
evaluation and management
Routine HCV Testing Not Recommended
(Unless Risk Factor Identified)
 Health-care, emergency medical, and public
safety workers
 Pregnant women
 Household (non-sexual) contacts of HCVpositive
persons
 General population
Routine HCV Testing of Uncertain Need
 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 HCVpositive
persons
Not confirmed as risk factor/prevalence low or unknown
Confirmed risk factor but prevalence of infection low
HCV Infection Testing Algorithm
for Diagnosis of Asymptomatic Persons
Screening Test for Anti-HCV
Negative
STOP
Positive
OR
RIBA for Anti-HCV NAT for HCV RNA
Negative
STOP
Additional Laboratory
Evaluation (e.g. PCR, ALT)
Negative PositiveIndeterminate
Medical
Evaluation
Positive
Negative PCR,
Normal ALT
Positive PCR,
Abnormal ALT
Source: MMWR 1998;47 (No. RR 19)
Medical Evaluation and Management
for Chronic HCV Infection
 Assess for biochemical evidence of CLD
 Assess for severity of disease and possible
treatment, according to current practice
guidelines
– 40-50% sustained response to antiviral
combination therapy (peg interferon, ribavirin)
– Vaccinate against hepatitis A
 Counsel to reduce further harm to liver
– Limit or abstain from alcohol
HCV Counseling
 Prevent transmission to others
– Direct exposure to blood
– Perinatal exposure
– Sexual exposure
 Refer to support group
Preventing HCV Transmission to Others
 Do not donate blood, body organs, other tissue
or semen
 Do not share items that might have blood on
them
– personal care (e.g., razor, toothbrush)
– home therapy (e.g., needles)
 Cover cuts and sores on the skin
Avoid Direct Exposure to Blood
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
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
HCV Counseling
Persons with One Long-Term Steady Sex Partner
HCV Counseling
Sexual Transmission of HCV
 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
Persons with High-Risk Sexual Behaviors
HCV Counseling
Sexual Transmission of HCV
 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
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, childcare
or other settings based on HCV infection
status
HCV Counseling