Hepatitis B

Hepatitis B is the one infection in the Eltern-Kind-Pass in which a positive result in the mother can remain almost entirely without consequence for the baby – provided the right thing happens in the first twelve hours after the birth. That is why testing is done in pregnancy, and why this test is one of the most effective in the whole of antenatal care.

Why hepatitis B is tested for in pregnancy

The hepatitis B virus can pass from mother to baby at birth. Without measures the probability of that, depending on the amount of virus in the mother’s blood, lies between ten and over ninety per cent. That alone would be reason enough to test – the real reason, though, lies in what happens afterwards.

An adult who becomes infected with hepatitis B recovers completely in over ninety per cent of cases. In a newborn it is the other way round: nine out of ten infected babies develop chronic hepatitis B. And out of chronic hepatitis B, cirrhosis and liver cancer arise over decades – in about a quarter of those affected.

The younger the person at infection, the more likely the chronic course. That is the central figure of this subject, and it explains why an examination that comes out negative in the great majority of women is nevertheless done in every one.

In Austria the test takes place as part of the third examination of the Eltern-Kind-Pass, between the 24th and 28th week of pregnancy, together with the second major blood test and the glucose tolerance test. When this window falls in your pregnancy is worked out by the maternity passport planner.

What the result means

What is looked for is HBs antigen, a component of the viral envelope. Its presence in the blood shows that an infection exists – whether recent or chronic, it does not say at first.

HBsAg negative means: no infection. That is the result in the overwhelming majority of pregnant women in Austria. With that the subject is settled.

HBsAg positive means: the virus is present. Further tests now follow, which establish how infectious the situation is – above all the viral load (HBV DNA) and the HBe antigen, plus liver values and the exclusion of other infections. This assessment belongs in the hands of infectious diseases or hepatology, and it happens unhurriedly: there is no reason to rush, because the decisive measures only take effect around the time of birth.

One point that often brings relief: a positive result says nothing about how someone lives. Hepatitis B is transmitted through blood, sexual contact and from mother to child. A considerable proportion of those affected living in Europe were infected as children in a country where it is widespread and know nothing of it until the pregnancy.

What happens with the baby

If the mother is HBsAg positive, the newborn receives within twelve hours of birth two injections in different legs:

• Hepatitis B immunoglobulin – ready-made antibodies that work at once but last only a few weeks. That is passive immunisation.
• Hepatitis B vaccine – the prompt for the baby’s own immune system, which takes weeks but lasts. That is active immunisation.

This combination is called simultaneous immunisation and prevents transmission in over 90 per cent of cases. The baby’s vaccination series is then continued according to the regular schedule, with a check on its success at the age of about nine to twelve months.

Where the mother’s viral load is very high, an antiviral medicine is given in addition from the last trimester, usually tenofovir. It lowers the amount of virus in the blood so far that the residual probability of transmission falls further. This treatment is well studied in pregnancy and is as a rule stopped after the birth.

The twelve hours are the only hard deadline in this subject. That is why a positive result has to be in the Mutter-Kind-Pass and known to the maternity hospital – not mentioned for the first time on the day of the birth. If you change practices or give birth in a different province, carry the result yourself.

Questions that come up regularly

Do I have to have a caesarean? No. A caesarean does not appreciably lower the risk of transmission when simultaneous immunisation is given. Planning the birth follows obstetric considerations as in any other pregnancy.

May I breastfeed? Yes. With simultaneous immunisation properly carried out, breastfeeding is expressly possible. This answer surprises many women and is one of the most important sentences of the whole conversation. With bleeding cracks in the nipple there is a temporary pause.

Can an amniocentesis transmit the virus? The risk is very small but not zero. With a high viral load it is weighed up whether an invasive test is really needed or whether non-invasive methods will do.

Does my partner have to be tested? Yes, and the household as well. Uninfected household members and partners should be vaccinated.

What about older siblings? Children vaccinated in Austria according to the regular schedule are protected through the six-in-one vaccine. In children born abroad or incompletely vaccinated, the status is checked and vaccination made good. They are tested only where infection was possible – for instance because they did not receive simultaneous immunisation at birth.

The vaccination

The hepatitis B vaccine contains only a genetically engineered surface protein – no viruses, neither live nor killed. It is therefore an inactivated vaccine and safe in pregnancy and while breastfeeding.

In Austria the hepatitis B vaccination is part of the six-in-one vaccine in infancy and is included in the free childhood programme. An adult without protection can catch up at any time: usually three doses on the 0 – 1 – 6 month schedule. For people at increased risk – medical occupations, household contacts, travel to countries where it is widespread, changing partners – it is expressly recommended.

After complete primary immunisation, protection lasts a very long time on current knowledge, in people with a healthy immune system usually for life. Routine boosters are not provided for in the general population; in certain occupational groups the antibody level is monitored.

A side effect rarely mentioned: the hepatitis B vaccine was the first vaccine of any kind to prevent a cancer. In Taiwan, where universal vaccination began in 1984, the frequency of liver cancer in children and young adults fell many times over. Only decades later did the HPV vaccine become the second.

How hepatitis B is transmitted

Through blood and body fluids. The virus is considerably more infectious than HIV – the smallest amounts of blood suffice, and it survives outside the body for several days.

The relevant routes are:

• unprotected intercourse – in Europe the commonest route in adults
• from mother to child during birth
• shared needles
• tattoos and piercings under inadequate hygienic conditions
• needlestick injuries in healthcare

It is not transmitted by shaking hands, through shared crockery, through food, by coughing or via a toilet seat. This list belongs here because a positive result regularly leads to exclusion in someone’s circle for which there is no basis at all.

How an infection runs its course

Between infection and illness lie six weeks to six months. A third of those infected notice nothing, a third have non-specific symptoms – tiredness, loss of appetite, joint pain – and a third develop the typical picture with yellowing of skin and eyes, dark urine, pale stools and pressure in the right upper abdomen.

In adults the illness heals completely in over ninety per cent of cases and leaves lifelong protection. Very rarely – in about one in a hundred – it takes a fulminant course with acute liver failure.

If HBs antigen remains detectable for longer than six months, it is called chronic hepatitis B. It runs silently over years and is frequently discovered by chance – not seldom at an antenatal examination. It is readily treatable: modern antiviral medicines suppress the virus reliably and thereby prevent progression to cirrhosis. Curable in the sense of eliminating the virus completely it is as a rule not, which is why treatment is long-term and care takes place at a specialist clinic.

Hepatitis A, B and C – what distinguishes them

The shared name regularly misleads. These are three completely different viruses that share only one thing: they affect the liver. Route of transmission, course, treatment and prevention differ fundamentally.

The last row is remarkable. With hepatitis C, against which there is no vaccine, an eight to twelve week course of tablets today leads to complete cure in over 95 per cent of cases. With hepatitis B, against which a very good vaccine exists, the opposite applies: treatment suppresses the virus reliably but usually does not eliminate it. Prevention and treatment are unevenly distributed here – one more reason to make use of the vaccine that is available.

Hepatitis A plays hardly any role in pregnancy and is not tested for routinely. Hepatitis C is not tested for universally in pregnancy in Austria, but is where there are risk factors – and is then treated, as a rule after the birth and after breastfeeding.

If you come from a country where it is widespread

In central Europe the proportion of people chronically infected is under one per cent. In parts of eastern and south-eastern Europe, in large parts of Asia and in Africa south of the Sahara it is many times higher; in some regions more than eight in a hundred people are affected.

Anyone born there was infected with raised probability as a child – frequently at birth or in the first years of life, so precisely at the age at which a chronic course is most likely. The infection then runs for decades without symptoms, and pregnancy is not rarely the first occasion on which it is noticed at all.

No cause for alarm follows from this, but a practical piece of advice: if you come from such a region, or your parents do, it is worth knowing your status – ideally before a pregnancy. The test is a blood sample. If it is positive, the illness is readily treatable, the baby can be protected, and your own liver can be checked regularly. If it is negative and there is no vaccine protection, that can be made good.

The consultation about this can take place at this practice in German or in English.

What matters for the woman herself

Chronic hepatitis B as a rule does not affect the pregnancy. The pregnancy for its part can change the liver values – usually harmlessly, occasionally with a flare after the birth, which is why checks in the postnatal period are provided for.

For contraception after the birth there are no particular restrictions: hormonal methods, the coil and barrier methods are all possible where the liver is stable. With advanced liver disease this is judged differently – here it is worth looking at the hormone-free options in the contraception comparison.

And for the time afterwards, what applies to any chronic illness applies here: regular monitoring is the real protection. Six-monthly ultrasound of the liver and measurement of liver values are provided for in chronic hepatitis B, because liver cancer is treatable at an early stage and barely so at a late one.

A positive result in everyday life

Chronic hepatitis B is notifiable in Austria – that concerns the health authority and serves surveillance, not publication. No duty to inform your circle, your employer or your insurer follows from it.

In working life there are few restrictions, and they concern exclusively activities involving invasive procedures with a risk of injury in healthcare – in surgery, for instance. For practically all other occupations, for childcare, catering, nursing or office work, nothing follows from a positive result.

In the household simple rules apply: toothbrush, razor, nail scissors and blood glucose meters are not shared, small wounds are covered, and spilled blood is taken up with an ordinary surface disinfectant. Kissing, hugging, eating together, sharing towels and bathing together are unproblematic. And most importantly: all household members and the partner should be vaccinated – after that the rest of the worry falls away too.

These sentences are set out at length because the social burden of a positive result is as a rule greater than the medical one. Anyone who knows what actually applies has less to explain.

Where to go from here

The test is part of regular antenatal care and does not have to be requested specially. If you are planning a pregnancy, it is worth settling your vaccination status beforehand – then the question is already answered should it arise.

A final thought for perspective: of all the examinations in the Eltern-Kind-Pass, the hepatitis B test has the most favourable ratio between effort and harm prevented. It costs a blood sample that is taken anyway. If it is negative – which it is in the great majority – it has cost nothing further. If it is positive, an injection in the first twelve hours of life prevents, with over ninety per cent probability, a chronic liver disease that would have accompanied the child for life. Such ratios are rare in medicine. Make an appointment. What else needs checking before a pregnancy is in the screening planner and under rubella.