The Krever commission report into the Canadian Blood system
was a significant watershed event for public health in the country. Link to access
page for Krever commission report
. While driven by the transmission
of HIV to blood recipients, the inquiry occurred at a critical time when new
developments were occurred on Hepatitis C.
Those that have been
around hospitals long enough knew well about the post transfusion problem of
non-A non-B hepatitis, the existence of which was likely known as early as 1974. It was not until the 1988 that the Hepatitis
C virus was actually identified, and not until the early 1990s that appropriate
virus specific testing was widely available.
(Recall that the HIV was ’discovered’
in 1982 and the virus identified in 1983 and testing was available in 1985)
Now some quarter of
Million Canadians are infected with Hepatitis C, and about 8000 new
infections annually. About 20% of those
infected are unaware of their infections.
Nearly two-thirds of new infections are associated with injection drug
use, but 15% with sexual activity and 10% through drug inhalation.
While there is evidence that the incidence is decreasing,
just as with HIV, data are often sparse and inadequate. The lack of markers of duration of infection
make dating of exposure difficult. Some
notable information on new infections that deserves attention Hep C
epidemiology from PHAC . Males have only a slightly higher rate of new
infection compared to females. The incidence
is highest in the 15-35 age group.
Notably that incidence rates in females 15-24 are higher than
males. Aboriginal rates are 3-5 times
that of non-Aboriginals and a cause for concern.
75% of persons infected with the virus develop a persistent infectious
state and are capable of transmitting to others. Most of these will develop some evidence of liver
disease over the duration of their lives, up to 20% will have evidence of
cirrhosis, and 5% will succumb to the direct effects of the disease. The later are probably lower estimates given
our lack of understanding. Antiviral
therapy can be provided based on certain criteria, which unlike HIV drugs, are more
often supplied at the patient’s cost than as a public good. The ability to comply with the medication regime
is a consistent criteria for treatment, and the use of intravenous drugs can
be, and is often, taken as a reason for not prescribing them. Genotype specific durations of therapy may
increase treatment success, however successful sustained response only occurs
in about ½ of patients who are provided the medication.
There are about 4 times as many Canadians infected with Hepatitis
C than HIV. A similar ratio exists globally. Yet, we persist in treated those infected
with Hepatitis C very differently from those with HIV.
So why the inequity based on disease? In the early years HIV received considerable
attention because of transmission not only to persons with blood dyscrasias (Haemophiliacs)
but also to populations of men who have sex with men (MSM) who are well integrated
into society and often in positions of authority and leadership. Hepatitis C, which also affected the Haemophiliac
population circulates more predominately in intravenous drug users and
frequently associated with very high rates in prison populations. Not the sort of population that readily
influences positions of power. Some of those
with Hepatitis C infection are for a variety of reasons more challenged with personal
resources and yet are frequently required to pay for their own treatment. Even politically, the current government expanded
the inequity when it moved to eliminate funding for Hepatitis C initiatives
after taking power while sustaining a greater degree of support for HIV based
initiatives. Within the health care
system, inconsistent support exists for dedicated Hepatitis C clinical
management whereas clients with HIV have near assured access. Training physicians in the management of
Hepatitis C has been underwhelming in its success while infectious disease specialists
ensure widespread management for those infected wtih HIV.
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