Hepatitis A, B and C
The following guideline is a brief overview of hepatitis screening and vaccination in the context of a sexual health check
Hepatitis A
- Transmission: faecal-oral, either from person to person or through contaminated food or drink
- Causes an acute (rarely fulminant) hepatitis
- Risk factors include travel to high prevalence countries, oral-anal sexual contact (rimming), and injecting drug use
- Outbreaks have occurred in men who have sex with men (MSM) overseas
- Injecting drug users account for 30% of cases in communities during outbreaks
- Acute hepatitis A is a notifiable infection
- Testing for hepatitis A virus (HAV) is not a universal part of routine sexual health screening
- Serology and vaccination have limited indications for funding in Aotearoa New Zealand
- Serology is not mandatory before vaccination. There is no harm in vaccinating an already immune person, however some groups with a higher probability of prior infection may wish to avoid the expense of vaccination
The following are unfunded indications for screening before vaccination:
- MSM and others engaging in oral-anal sexual contact
- People who inject drugs
- People who have hepatitis B or C (superinfection with HAV leads to increased morbidity and mortality)
- People travelling to high-risk countries
Repeat testing is unnecessary unless unexplained liver disease
- HAV testing is not funded in Aotearoa New Zealand, unless acute infection is suspected
- Routine testing for HAV immune status = total HAV antibody (Ab)
- Differential testing for HAV IgG and IgM is limited to patients suspected of having acute HAV (jaundice and deranged liver function tests)
- Serology is not mandatory before vaccination. There is no harm in vaccinating an already immune person, however some groups with a higher probability of prior infection may wish to avoid the expense of vaccination
- Total HAV Ab < 20 IU/mL
- Susceptible
- Offer vaccination if risk, and patient willing to pay
- Total HAV Ab > 20 IU/mL and no suspicion of acute hepatitis
- Previous infection or vaccination
- Reassure the patient
- No further action required
- Suspicion of acute hepatitis and total HAV Ab > 20 IU/mL or positive HAV IgM with or without positive HAV IgG
- Possible acute infection – IgM remains positive for 6 months or more
- Request liver function tests and HAV IgM if not already done
- Supportive care and monitoring
- Advise avoiding food-handling and sexual contact (including oral-genital and oral-anal) until non-infectious
- Infectiousness lasts from 2 weeks before until 1 week after onset of jaundice
- Notify public health immediately
- Vaccination is only funded for limited indications in Aotearoa New Zealand
- Serology is not mandatory before vaccination. There is no harm in vaccinating an already immune person, however some groups with a higher probability of prior infection may wish to avoid the expense of vaccination
- Consider unfunded vaccination for the following target groups in the context of a sexual health check:
- MSM and others engaging in oral-anal sexual contact
- People who inject drugs
- People who have hepatitis B or C (superinfection with HAV leads to increased morbidity and mortality)
- See the Immunisation Handbook 2020 for vaccination schedule
- HAV infection does not appear to be associated with worse clinical outcomes in people living with HIV
- HAV vaccine is recommended (unfunded) for people living with HIV, who have additional risk factors (see target populations above)
Hepatitis B
- Transmission: contact with infectious blood or body fluids including during childbirth, contact with broken skin, sexual intercourse or injecting drug use
- Broad spectrum of disease from subclinical to fulminant hepatitis
- Persistent infection can lead to chronic liver disease, including cirrhosis or hepatocellular carcinoma
- If hepatitis B virus (HBV) is acquired as an adult, the majority will have immune clearance and develop subsequent immunity. Only 5-10% of adults will develop chronic HBV infection. This contrasts with chronic infection rates of over 90% in neonates and 20-50% of children under 5 years of age
- Hepatitis B vaccination has been a part of the infant immunisation schedule in Aotearoa New Zealand since 1988
- By December 2019, 93% of children aged under 2 years had completed a primary course of hepatitis B vaccination, which confers lifelong immunity in approximately 95% of those vaccinated
- Acute hepatitis B is a notifiable infection
- Testing for HBV is not a universal part of routine sexual health screening
- People born in Aotearoa New Zealand after 1988 are likely to have been vaccinated as babies, with lifelong immunity in approximately 95% of those vaccinated
- While serological testing after vaccination is not routinely recommended, serum anti-HBs antibody ≥ 10 IU/L, measured at least 1-2 months after the course of immunisation, is a correlate of long-term protection
- In most people, antibodies wane to undetectable levels by 7 years after the last vaccination, however sustained immune memory and long-term protection continue to occur in immune-competent adults without the need for boosting
- In the context of a sexual health check, the following target groups should be offered serological testing and vaccination, unless known to be immune:
- MSM
- People living with HIV
- Sex workers
- People who inject drugs
- People of Māori, Pacific or Asian ethnicity born in Aotearoa New Zealand before 1988
- Immigrants of any age from Pacific Island, Asian, Middle Eastern or African countries
- People who have been incarcerated
- Contacts of people with HBV
- Following non-consensual sexual intercourse
- Repeat testing is unnecessary if vaccination is declined unless unexplained liver disease, or if patient is using HIV pre-exposure prophylaxis (PrEP)
- Serological testing after vaccination is only indicated in people at higher risk of exposure to HBV, or those at higher risk of having severe disease
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High-risk individuals, for whom serological testing is indicated after vaccination (adapted from Immunisation Handbook 2020)
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- Routine testing for HBV immune status = hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (HBsAb)
- HBsAg positivity indicates active infection
- HBsAb > 10 IU/L indicates immunity (if HBsAg negative)
- If HBsAg positive, refer to the Hepatitis Foundation of New Zealand for monitoring and onward referral as indicated
- Hepatitis A and C serology should be requested. People who are susceptible to hepatitis A should be offered unfunded vaccination
- Sexual partners, first degree relatives and household contacts should be advised to attend their GP for screening and vaccination if not immune
- See Immunisation Handbook 2020 for vaccination schedule
- HBV infection is associated with worse clinical outcomes in people living with HIV
- HBV vaccine is therefore recommended and funded for people living with HIV
- Some HIV antiretroviral therapy has activity against HBV, enabling targeted therapy in people with co-infection, without an increase in pill burden
- People with chronic Hepatitis B who would like to use PrEP should be referred to or discussed with a sexual health specialist
Hepatitis C
- Transmission: exposure to infected blood or body fluids. Most newly acquired infections in Aotearoa New Zealand are from injecting drug use. Hepatitis C is rarely sexually transmitted; the risk is greatest for MSM, especially in association with injecting drug use
- Most people who contract hepatitis C virus (HCV) are asymptomatic. Spontaneous clearance occurs in approximately 20-25% of people with the infection, however 75-80% develop chronic hepatitis C, with risk of cirrhosis, hepatocellular carcinoma, and risk of transmission of HCV to others
- The National Hepatitis C Action Plan for Aotearoa New Zealand – Māhere Mahi mō te Ate Kakā C 2020-2030 - aims to eliminate Hepatitis C as a public health threat by 2030, in line with World Health Organisation (WHO) hepatitis C global elimination goals
- Effective treatment is available
- Risk factors for HCV:
- Injecting drug use
- Blood transfusion in Aotearoa New Zealand before July 1992
- Receiving health care in a region with high HCV prevalence
- Incarceration
- Tattoo or body piercing not performed in a licensed premises in Aotearoa New Zealand
- History of acute hepatitis, jaundice or abnormal liver function
- Being born to a mother with HCV infection (5% risk of transmission)
- People cannot develop immunity to HCV, therefore re-infection is possible
- Acute HCV is a notifiable infection
- Testing for HCV is not a universal part of routine sexual health screening
- In the context of a sexual health check, the following target groups should be offered serological testing:
- People who inject drugs and their sexual partners
- People who have shared injecting equipment, needles and sharp objects (including household items like scissors, razors, toothbrushes) with a known HCV-positive person
- People living with HIV, particularly MSM living with HIV (test annually)
- MSM prescribed HIV pre-exposure prophylaxis (PrEP) (test annually)
- Recipients of blood transfusion or blood products before July 1992 (in Aotearoa New Zealand)
- People who have received medical or dental treatment in a country with high HCV prevalence
- People who have had tattoos or body piercing in circumstances where infection control procedures could be suboptimal
- People who have been incarcerated
- Repeat annually for those with ongoing risk
- Routine testing for hepatitis C = HCV Ab
- Patients who have previously cleared HCV will continue to test positive for HCV antibody. If ongoing risk, request HCV RNA for future screening (with clinical details on laboratory form)
- HCV antibody positive indicates current or past infection. Request HCV RNA to check if infection is current
- If HCV RNA positive, infection is current. Refer to local protocols for management. Effective treatment is available
- Hepatitis A and B serology should be requested. People who are susceptible to hepatitis A or B should be offered vaccination (hepatitis A unfunded, hepatitis B funded)
- There is no vaccine available for HCV
- HIV co-infection is associated with a reduced rate of spontaneous HCV clearance, and more rapid HCV disease progression
- All people with HIV and HCV co-infection should be offered treatment for both
- Request specialist advice for co-infection