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Viruses and the liver
Viruses and the liver: from Hepatitis A to G: In other words "All you need to know about Hepatitis."
Hepatitis is a disease characterised by an inflammation of the liver and is more serious than one might think because it involves an organ which is so important in the regulation of bodily functions. Hepatitis may also be caused by non-viral substances such as chemicals, pharmaceuticals and alcohol.
The term "Viral Hepatitis" is commonly used for a variety
of diseases caused
by viruses which may cause inflammation of part or generally all of the hepatic
tissue, which often results in a swelling and increased fragility of the
liver itself, and sometimes a yellowing of the skin (the famous jaundice or
jaundiced look, as it was once called).
Every year in Italy, according to data deriving from the National System
of Specific Surveillance of Viral Hepatitis, SEIEVA of the National Health
Institute (l’Istituto Superiore di Sanità), still today some 7
000 cases of acute viral hepatitis are recorded, but this represents only a
fraction of the Hepatitis which actually occur, because most of these, especially
those which are from Hepatitis C are completely asymptomatic.
The most common types of Viral Hepatitis, caused by the respective viruses
denominated by alphabetical letters are:
- Hepatitis A, previously called Infective Hepatitis, is most common in children
of third world countries, but is also still quite frequent in the developed
western world. Currently in Italy, the most affected are youths between
15 and 24 years, mostly male and resident in the South. It accounts for about
half of all cases of acute viral hepatitis (3300 cases every year in Italy).
Hepatitis A is usually a benign infection, with an incubation period of less than a month, spread by inter-personal contact or by means of viral contamination of water or food, and therefore with oral-faecal transmission. The infection clears up in a few weeks and never becomes chronic. On rare occasions it may have a “galloping” course which becomes fatal. It can be more dangerous if contracted as an adult. - Hepatitis B, once called Serum Hepatitis ( Hepatitis from Serum ), is the most common form of Hepatitis, with 300 million carriers world wide, and in Italy, an estimated 1650 new cases per year and some one million carriers of the B virus despite the introduction of obligatory vaccination. The B virus can cause a serious form of Hepatitis, has an incubation period which varies from 20 days to 6 months, and often has non-specific or flu-like symptoms. Hepatitis B develops into a chronic disease ( which means uninterrupted occurrence for more than 6 months) in 10% of infected subjects each year. If untreated, the risk of developing Cirrhosis (liver scars ) and Liver Cancer is highest in patients with chronic Hepatitis B.
- Hepatitis C, once known as "Hepatitis non-A, Hepatitis non-B",
is, currently in Italy, the most frequent form of chronic hepatitis and affects
about 1.500.000 people, mainly adults and the elderly, who have contracted
the infection decades earlier, from transfusions or contact with infected
needles or sanitary material. In Italy today there are some 1000 new cases
of Hepatitis C.
The acute form is almost always asymptomatic and has an incubation period of 10 days to 8 months, on average 40 days. Unfortunately in most cases, i.e. in some 70-75% of cases, it tends to become chronic.
As with chronic Hepatitis B, if left untreated, the chronic form has a high probability of developing into Cirrhosis in the arc of 15-40 years and some of these Cirrhoses can then develop into Liver Cancer. Hepatic insufficiency from C-virus Cirrhosis is the principal cause of Liver Transplants in the United States of America. - There are other forms of Hepatitis which are less common: these include Hepatitis D, which, even though it is very serious, can only be present in subjects already infected with Hepatitis B; Hepatitis E, which is transmitted in ways similar to Hepatitis A and causes a form of Hepatitis similar to A; Hepatitis G , which we do not even know whether it can cause damage to the liver; and others less understood and however very rare in Italy. Other viruses, especially members of the Herpes Virus Family, including the Herpes Simplex Viruses, the Chickenpox viruses, the infective Mononucleosis Viruses and others can infect the Liver.
One could write an entire book on viral Hepatitis, but both for reasons of space as well as a desire to be more informative and practical, we prefer to proceed by means of a few common questions, which a person who discovers he has been in contact with these viruses, may ask, usually of his doctor:
How is viral hepatitis transmitted?
A summary of the different ways in which the most common forms of Hepatitis
(A, B and C) are transmitted and how they may be avoided is reported
in table 1.
Hepatitis A and E are excreted and spread in faeces. Direct contact with the faeces of an infected person, indirect contamination of food with faecal material, water supply, raw mollusc, hands and utensils can result in a sufficient quantity of virus entering the mouth and causing infection.
Hepatitis B is transmitted from mother to child at the moment of birth or immediately afterwards, by means of sexual contact, blood transfusions or contaminated needles. However, approximately one third of cases in the general population derive from unknown causes. The virus may also be transmitted from adult to child within a family.
Hepatitis C is transmitted from one
person to another in the blood or by means of contaminated needles. While
sexual transmission and mother-child diffusion may occur, they are not common
modes of transmission.
People who are at risk of infection from Hepatitis B or C include workers
in the health sector, people with multiple sex partners, those using intravenous
drugs and haemophiliacs. Anyone who has had a tattoo, a body piercing or
a blood transfusion (prior to a routine screening of blood donors which began
in 1972 for Hepatitis B and in 1990 for Hepatitis C) and those who are in
close familial contact with an infected person are themselves at a high risk
of being infected. Hepatitis B or C can also be transmitted by sharing toothbrushes
or nail files contaminated with infected blood – even though these forms
of transmission occur rarely.
How can I avoid viral Hepatitis?
Viral Hepatitis can be avoided by simply following the advice given in
figure 1.
What are the symptoms of Viral Hepatitis?
Viral Hepatitis is often a silent killer. The most common symptoms
are tiredness, a slight temperature, muscular and articular pain,
nausea, vomiting, loss of appetite, vague abdominal pains and
sometimes diarrhoea. Many cases are not diagnosed because
the symptoms are similar to those of influenza or they
may be very slight or even absent. A few patients
may note that their urine is dark while their faeces
are lightly coloured, followed by jaundice in which the skin and whites
of the eyes appear yellow. Itchy skin irritation may
occur. The only
way to positively identify these illnesses is by means of blood
tests. If you suspect that you may have Hepatitis or of you think
that you have been in contact with an infected person or a contaminated
object, you must see a doctor as soon as possible.
Can I get Hepatitis again?
Yes, because there are 7 or more types of hepatic viruses.
But you would never be re-infected by the same virus
as each one produces its own immunity. However,
sometimes the Hepatitis B, C and D viruses
remain in one’s
body for ever. They may cause recurrences of the Hepatitis,
which seem like a new disease.
Who is a carrier and how will I know if I am one?
A carrier is a person who
has Hepatitis B, C or D in
the blood, but all the other
symptoms are absent, and all
the other signs of Hepatitis,
including
the transaminases, are normal
for a long time. But since
the virus is present in the
blood, it may be transmitted
to others. Carriers of chronic
Hepatitis A do not exist. Carriers of Hepatitis B may be recognised by a simple
and specific blood test. Certain carriers are contagious while others are
not. Even this may be determined by a simple blood test. Tests for Hepatitis
C carriers have been developed.
Before a transfusion, all blood is examined for anomalous liver functionality
and for the Hepatitis B and C viruses. These tests have reduced the percentage
of post-transfusion Hepatitis C from 8-10% to 0.5%. AVIS identify the
donors in whom these anomalies have been found. Hepatitis D may be discovered
by a simple blood test which looks for the anti-viral antibodies in subjects
who are positive for Hepatitis B. In addition, tests for Hepatitis E and
G have been developed, even though they are not yet available for routine
diagnostics.
If I am pregnant and I am a carrier of a hepatitis Virus or suffering from
Hepatitis, is my unborn child at risk?
Hepatitis does not increase the risk of still births nor of malformation.
However abortions happen more frequently and conception is more difficult
for women with chronic Hepatitis. Since vaccination against Hepatitis B is
obligatory for all new-borns in Italy, your being a carrier does not carry
a serious risk for your baby, so long as it is known. All pregnant women
must hence be tested for Hepatitis B and possibly also for Hepatitis C, even
though the risk of transmission to the new-born in the latter case is very
low and is heavily dependent on the quantity of the mother’s blood which
comes into contact with that of the new-born.
The greatest risk of infection at the birth occurs when a mother who is a
Hepatitis B or C carrier, contracts an infection from another virus (C or
B) during pregnancy, i.e. contracts a Hepatitis.
The possibility of the child becoming infected in this case is very high.
Infection of the child in the uterus is very rare. Most babies infected become
carriers. Some become gravely ill, others manage to avoid infection.
What should I do if I have been exposed to Viral Hepatitis or suspect that
I have it?
Consult your doctor, and if he agrees, also a specialist ( if you wish
to see someone from our association, see final rectangle) who will examine
you and request some blood tests to confirm the diagnosis, identify the specific
type of Hepatitis and advise you about the diet you must follow and activities
you must undertake. Your acquaintances must be notified of your infection
and there is a possibility that gamma (immuno) globulins and/or vaccination
may be necessary.
Should I see a specialist if I have Hepatitis?
The majority of general practitioners can treat a patient presenting with
ordinary Viral Hepatitis. Nevertheless, referral to a specialist in liver
disease (Hepatologist, Gastroenterologist) will be necessary if the disease
appears unusually serious or if complications are recognised (if you wish
to see someone from our association, see final rectangle).
Are there cures for Hepatitis?
If you are talking about Hepatitis A, most of the time, simple rest and
adequate diet will lead to recovery – and NEVER to the disease’s
becoming chronic. If you result positive to the test for Hepatitis B or C,
today there are various treatments available to patients who can undergo
them or those who are known from the start to be able to respond well to
them. So, if you think you may be infected, do not hesitate to contact your
doctor immediately.
Can Hepatitis cause Cancer ?
There is a high incidence of Liver Cancer in certain African and Asiatic
States, where there are Hepatitis B carriers, and it seems
to be related to the state of chronic Hepatitis B carriers. There is an increase
in the number of Liver Cancer cases in patients with chronic Hepatitis C,
but it is not known whether the risk of developing cancer is a high as that
with Hepatitis B. Carriers of Hepatitis B in the Far East are at a much higher
percentage risk of developing Liver Cancer than those in the United States
of America or in Italy. However for greater clarity, more research in this
direction is needed.
Are there vaccines and can the disease be prevented ? How can the spread
of Hepatitis be minimised ?
Table 2 reports the dosage and administration mode of the two vaccinations
which are available today: for Hepatitis A and Hepatitis B. The vaccine for
Hepatitis A is given in 2 doses, the second 6-12 months after the first.
Two types of vaccines are available to prevent Hepatitis B. Both are safe
and effective and seem to prevent infection if started within a few days
after exposure. Today in Italy, vaccination against Hepatitis B is obligatory
at birth, so we can expect Hepatitis B to almost completely disappear from
our country within a few years. The anti-Hepatitis B immunoglobulins may
also prevent infection after exposure, but must be given within 48 hours
to be useful. Hepatitis D is prevented the same way as Hepatitis B. No vaccine
or immunoglobulin is yet available for Hepatitis C or E.
Adequate hygiene services and good personal hygiene reduce the propagation
of Hepatitis A and E. If there is some doubt as to the safety of the water,
it must be boiled before use. Similarly, in areas where hygiene services
are dubious, food must be well cooked and fruit must be peeled. Sanitary
personnel who are involved in patient treatment especially in the first two
weeks of an illness, must wash their hands with medicated soap, use clean
utensils, and wash bedding and clothing with soap and water. People planning
to travel in areas where Hepatitis A is widespread, are advised to be vaccinated
beforehand or to take immunoglobulins with them. Protection is effective
for two to six months. To prevent the spread of Hepatitis B, it is however
necessary to avoid exposure to infected blood or body fluids. Don’t have
intimate contact or share razors, scissors, nail files, toothbrushes or needles.
Above all, drug addicts must avoid exchanging needles and/or syringes. Dentists,
doctors, nurses, laboratory technicians and others who are involved with
blood, with surgical procedures or the manipulation of cutting instruments
used on patients who are carriers of or who are ill with Hepatitis, must
be informed so that they may take adequate precautions. Family members and
other cohabitants should be advised to consult their house doctors about
immunoglobulin injections or vaccination.
Are transfusions safe today ?
For the most part, yes. Today, in Italy, the risk of getting any type of
Hepatitis from a transfusion, is lower than 5 in 10.000 transfusions. The
risk of contracting Hepatitis B from a transfusion today is practically non-existent,
while that for Hepatitis C is greatly reduced, with the prospect of further
reduction in the near future. Today, all products deriving from blood are
highly checked by means which are better and more sensitive than in the past.
If
I have been infected by a transfusion in the past, can I get compensation
for the damage suffered?
A recent law (L.210/92) establishes the possibility of compensation for someone
who has contracted an infection as a result of blood transfusion or use of
blood derivatives. Official documentation is necessary about previous transfusions,
proof of non-infection prior to the transfusion in question and evidence
of current infection.
Obviously this article will not have satisfied the curiosity of anybody interested in the subject. If you would like to have further information about Hepatitis, ask you doctor or directly contact the Foundation for the Study of Liver Disease at any of its centres.