An imperceptible amount of blood from someone who has the virus
will transmit the infection if it gets into someone else’s bloodstream,
e.g. through a cut or scratch.
Hepatitis C (and B) can be passed on by using any injecting
equipment which has been in contact with an infected person’s blood. Just one occasion of sharing a needle can be sufficient for someone to become infected with the virus. An increasing number of people who injected just a few times many years ago are now being diagnosed with hepatitis C.
Lending and borrowing injecting equipment is common. This
includes not only syringes and needles, but also paraphernalia such as spoons and
other containers for mixing drugs, water, swabs, filters, tourniquets
and utensils such as lighters and knives. The probability of becoming infected after sharing paraphernalia is currently not known, but must be treated as a potential and important risk.
Some IDUs are unclear about what ‘sharing’ means. For example,
they believe that using the same equipment as a long-term partner is
not sharing and hence safe. Others class sharing as using equipment
at the same time as someone else and are unaware the virus may
survive for several days on dirty needles and other
paraphernalia.
Occasional users are likely to share because drug use is usually
unplanned and first experiences of injecting are nearly always with
borrowed equipment. Long-term users who normally practice needle
exchange still share from time to time.
Bodybuilders who inject steroids are also possibly at risk of infection,
definitely so if they share injecting equipment. They are often
unaware that sharing any drug paraphernalia with anyone can
transmit hepatitis C.
The potential risk of infection applies to injecting practices such as re-using
filters, drawing up from a communal pot of water, using the same
spoon as someone else, frontloading, backloading, flushing out and
skin popping (for the meaning of these terms, see ‘Useful words’ on
page 26). If any equipment is used without adequate cleaning, it is
likely to contain blood which will be injected into the next person.
There is also some concern that sharing straws for snorting cocaine
may be a route of infection due to nose bleeds, however, this risk needs to be examined further.
Blood transfusion and blood products
Some people who received blood transfusions before screening for
hepatitis C was introduced in September 1991 may be infected. Blood
and blood products may not be screened for the virus in some foreign
countries. People who received blood products, such as haemophiliacs
prior to 1985 in England and Wales, and 1987 in Scotland will have
been at risk of infection. Treatment of blood products to prevent HIV
infection also prevents hepatitis B and C as well.
Sex
Sexual transmission of hepatitis C is thought to be rare but
does occasionally occur.
Passing on hepatitis C is more common if the person has a sexually
transmitted illness. Also, anal or rough sex is more likely to pass on
the infection. Oral sex is thought to be low risk.
People with more than one sexual partner should use condoms, as
there is evidence that those with many sexual partners have an
increased risk of being infected and they will be at risk from many
other sexually transmitted infections.
Couples are often worried about infecting each other but when one
partner is positive and the other negative after many years it seems
easonable to advise that, if the relationship is stable and long term, it
is unnecessary to change to using condoms for protection.
Sex during menstruation is best avoided.
Social contact/household transmission
Infection is not acquired through normal social contact, for example,
from a cup or by touching an infected person. However, if a person
is infected they should use their own personal items such as a
nailbrush, scissors, toothbrush or razor and be meticulous about cleaning up any
blood from cuts or scratches. Undiluted household bleach should be
used to clean up blood from floors and work surfaces. Scratches,
cuts and wounds should be carefully cleaned and covered with a
waterproof dressing or plaster.
Acupuncture, tattoos, body piercing
A few people have become infected by non-sterile needles being
used for ear and body piercing, acupuncture (HCV long-term follow-up
on this is still in progress; outbreaks of hepatitis B virus (HBV)
infection have also been reported) and tattooing. Disposable needles
from a sterile packet should be used every time and the practitioner
involved should be appropriately registered
.
Saliva
The virus has been detected in saliva but it is unlikely that infection can
be transmitted by kissing unless, for example, both people have cuts
in the mouth or bleeding gums. To reduce the possibility of infection,
IDUs should not use someone else’s toothbrush and should maintain
good oral hygiene.
Mother to baby
The risk of a mother with hepatitis C infecting her baby during
pregnancy or during the birth is about six per cent. Whether this
happens in the womb, during delivery or immediately after the birth is
not known, but it is not during conception. The risk appears to be
greater in women with high levels of the virus in the blood or in those
who are also infected with HIV.
Hepatitis C antibody testing is of limited value in infancy because maternal antibody may be present up to 13 months of age, and occasionally up to 18 months of age. Diagnosis of infants is therefore based on
a molecular test for the virus itself (called an HCV PCR test) which tests for the presence of viral RNA.
Infants are considered infected if HCV RNA is positive on more than 2 occasions. It is important to note that the sensitivity of PCR for diagnosis increases with time (from 22% in those less than 1 month old, to 97% in those older than 1 month). Therefore, HCV PCR tests for the virus should be undertaken between 1-3 months of age. A practical recommendation would often be to delay testing till 8 weeks to coincide with routine immunisations.
Doctors do not yet know if the disease that occurs when a baby is infected will go on to become serious.
Infected mothers are often concerned about passing the virus on to
their other children. As long as the precautions listed on page 12 are
followed, household transmission is a low risk. Kissing or cuddling a
child is safe.
Breastfeeding
Although the virus has been isolated from the breast milk of infected mothers, most doctors consider breastfeeding to be safe. In theory, infection could be possible if a mother has cracked nipples which bleed and a baby has a cut in the mouth. Breastfeeding is not recommended if the mother is HIV positive.
Unknown
In some cases doctors cannot identify how people came to be infected.