Hepatitis C
Queensland Health Guidelines for Public Health Units
Revision History
Version | Date | Changes |
1.0 | May 2012 | Full revision of guidelines. |
Infectious Agent
The agent is hepatitis C virus (enveloped RNA virus) with multiple genotypes and subtypes.
Notification Criteria1
Clinical evidence2Clinical hepatitis within the past 24 months (where other causes of acute hepatitis have been excluded) defined as:
- Jaundice
OR - Bilirubin in urine
OR - Alanine transaminase (ALT) seven times the upper limit of normal.
Laboratory definitive evidence (newly acquired hepatitis C)
- Detection of anti-hepatitis C antibody from a person who has had a negative anti-hepatitis C antibody test recorded within the past 24 months
OR - Detection of hepatitis C virus by nucleic acid testing from a person who has had a negative anti-hepatitis C antibody test result within the past 24 months
OR - Detection of anti-hepatitis C antibody from a child aged 18 to 24 months
OR - Detection of hepatitis C virus by nucleic acid testing in a child aged 1 to 24 months.
Laboratory definitive evidence (unspecified hepatitis C)In a person with no prior evidence of hepatitis C virus infection
- Detection of anti-hepatitis C antibody
OR - Detection of hepatitis C virus by nucleic acid testing.
Laboratory suggestive evidence (newly acquired hepatitis C)Detection of anti-hepatitis C antibody, or hepatitis C virus by nucleic acid testing.
Notification Procedure
Pathology Laboratories
To notify on confirmation by usual means.
Reporting to NOCS
Only confirmed cases should be reported.
Confirmed case (newly acquired)A confirmed case of newly acquired hepatitis C requires either:
- Laboratory definitive evidence for newly acquired hepatitis C
OR - Laboratory suggestive evidence AND clinical evidence.
Confirmed case (unspecified)A confirmed case of unspecified hepatitis C requires laboratory definitive evidence for unspecified hepatitis C AND that the case does not meet any of the criteria for a newly acquired case AND is aged more than 24 months.
Objectives of Surveillance
To monitor the epidemiology of hepatitis C to better inform public health interventions.
Public Health Significance and Occurrence
Worldwide distribution. Hepatitis C virus (HCV) prevalence is directly related to the prevalence of persons who routinely share injecting equipment and to the prevalence of poor parenteral practices in health care settings. Severe hepatitis, chronic hepatitis, chronic liver disease, cirrhosis, liver failure and hepatocellular carcinoma, perinatal transmission and extra-hepatic manifestations are all potential sequelae of hepatitis C infection. WHO estimates that some 130-170 million people are chronically infected with HCV. HCV is a major cause of end stage liver failure and liver transplantation worldwide.
Current estimates suggest that more than 300,000 Australians have been infected with HCV and that approximately 10,000 new infections are occurring each year. Most current and new infections in Australia are in people with a history of injecting drug use. Higher rates of infection are also seen in people born in countries where there is a high prevalence of hepatitis C and people with a history of imprisonment (independent of injecting drug use). Healthcare associated infection is uncommon in Australia, however in 2010/2011 around fifty patients of a Melbourne clinic were confirmed as having been infected with the same genotype as a health care worker who had worked at the clinic.
There are at least twelve major genotypes of HCV. Different genotypes have varying prevalence around the world. At present the main genotypes found in the Australian population are 1 (54%), 3 (36%) and 2 (6%).
Clinical Features
Acute infections are asymptomatic in more than 90% of cases, however 50-85% of those infected will develop chronic infection. When clinically apparent the onset of acute infection is usually non-specific with anorexia, abdominal discomfort, nausea and vomiting. Progression to jaundice is less frequent than with hepatitis B. Fulminant hepatitis with liver failure has been described in rare cases. Although HCV infection can lead to hepatic inflammation and steatosis, the major pathologic consequence of persistent HCV infection is the development of hepatic fibrosis, which may progress to life threatening cirrhosis and poses a greatly increased risk of hepatocellular carcinoma. These long-term complications generally occur more than 20 years after the onset of infection, though more rapid progression has been reported. There are wide estimates (5% to 25%) of the probability of cirrhosis occurring within 20 years of infection and little information available on progression beyond 30 years
The natural history of HCV infection in children is not well understood, but significant liver disease including chronic hepatitis, cirrhosis and hepatocellular carcinoma have been reported in adolescence.
Reservoir
Humans.
Mode of Transmission
The predominant mode of transmission is parenteral, via percutaneous contact with infected blood or blood products. Blood and blood products (and organs and other tissues) have been screened in Australia since February 1990, minimising transmission risk. Sexual and perinatal transmission may also occur. Estimates of perinatal transmission frequency range from 0% to 7%. Perinatal transmission is increased if the mother is HCV PCR positive and co-infected with HIV. Sexual transmission is rare but risk may be increased by receptive anal intercourse, especially if co-infected with HIV. Spread via household contact (probably through sharing toothbrushes and razors, which may be contaminated with traces of blood) occurs infrequently.
Incubation Period
Ranges from 2 weeks - 6 months, commonly 6 - 9 weeks. Current HCV antibody tests become positive two to three months after exposure. Chronic infection may persist for up to 20 years before the onset of cirrhosis or hepatoma.
Period of Communicability
Communicability extends from one or more weeks after the onset of viraemia and indefinitely in the chronic infection state. Peaks in virus concentration appear to correlate with peaks in ALT activity.
Susceptibility and Resistance
All people appear susceptible to infection. The degree of immunity following infection is not known but may be sub-type specific or short lived. Repeated infections with HCV have been documented. If infection resolves and the virus is cleared, the person can be re-infected with the same or other genotypes.
Management
Cases
Investigation
Follow up cases of newly acquired hepatitis C in consultation with the attending medical practitioner.
Identify possible source of infection. If could be transfusion related contact the Australian Red Cross Blood Service, phone: 13 14 95
The follow up of all other cases is at the discretion of the public health unit.
Restriction
Health care workers who are HCV RNA positive should read Australian National Guidelines for the Management of Healthcare Workers Living with Blood Borne Viruses and Healthcare Workers who Perform Exposure Prone Procedures at Risk of Exposure to Blood Borne Viruses
Counselling
The case should be advised of the nature of the infection and its mode of transmission:
- Do not donate blood or other biological material
- Do not share needles, syringes, spoons, filters or any other injecting equipment
- Do not share razors, toothbrushes or nail/hair clippers or similar items which could become contaminated with blood
- Minimise alcohol intake
- Vaccination against hepatitis A & B
Contacts
Contact TracingRoutine contact tracing only required for newly acquired cases.
Definition
From 6 months prior to onset of acute symptoms (where known), otherwise on a case by case basis according to history.
High RiskRecipients of HCV positive blood product transfusion.
Person sharing contaminated needles/syringes or other injecting equipment with index case.
Intermediate Risk
Occupational needle-stick injury associated with hepatitis C contaminated needle/syringe.
Low Risk
Household members of a case
Sexual exposure to a case
Investigation
Anti-HCV and LFTs as appropriate.
Prophylaxis
No prophylaxis has been shown to be effective.
Counselling
Contacts should be advised of the nature of the infection and its mode of transmission.
Special Settings
Health care settings. Refer to the following:
- Australian National Guidelines for the Management of Healthcare Workers Living with Blood Borne Viruses and Healthcare Workers who Perform Exposure Prone Procedures at Risk of Exposure to Blood Borne Viruses 19/12/2018
- Implementation Standard for Management of Exposure to blood and body fluids 04/06/2012.
Antenatal care
Antenatal care should include a comprehensive assessment of hepatitis C risk factors. Women found to be at higher risk of hepatitis C infection or exposure should be offered hepatitis C antibody screening.
Preventive Measures
- Screening of donated blood and tissues.
- Standard and transmission based infection control precautions in healthcare settings.
- Needle and syringe programs, and other harm minimisation initiatives.
- No vaccine currently available - difficulties in development include the sequence diversity between viral genotypes.
- No post-exposure prophylaxis has been shown to be effective.
Summary
Prepare a report of any investigation for the Communicable Diseases Branch, Queensland Health, on request.
References
Commonwealth Department of Health and Aged Care, National Hepatitis C Resource Manual. 2008.
Heymann, D. (Ed). 2008. Control of Communicable Diseases Manual, 19th edition. American Public Health Association: Washington.
Mandell GL, Bennett JE and Dolin R, 2010. Mandell, Douglas and Bennett's Principles and Practice of Infectious Diseases, 7th Ed. Churchill Livingstone, Philadelphia.
Queensland Health. Implementation Standard for Management of Exposure to blood and body fluids 04/06/2012.
Sydney Sexual Health Centre. Australasian Contact Tracing Manual, 4th ed. 2010. The Australasian Society for HIV Medicine; Sydney.
1 Detection of anti-hepatitis C antibody requires positive initial test plus confirmation by appropriate supplemental test
2 While hepatitis C is not clinically notifiable under the Public Health Act, clinical evidence is required for confirmed newly acquired cases where there is laboratory suggestive evidence only