Viral
co-infection now recognized as a major health problem
The
World Health Organization says a “silent epidemic” of viral hepatitis affects a
large part of the world’s population, causing over 1.4 million deaths every
year, yet it remains largely unknown or ignored.
It is
estimated by the WHO that 240 million people are chronically infected with the
hepatitis B virus and more than 185 million people are infected with hepatitis
C. These numbers far exceed the number of people living with HIV, estimated at
34 million.
Viral
hepatitis co-infection in those living with HIV is now recognized as a major
public health problem resulting in increased morbidity and mortality including
for those on antiretroviral therapy. Chronic Hepatitis B infection affects 10
percent of HIV sufferers worldwide. By contrast, Hepatitis C affects 20 percent
of HIV sufferers, with a majority of them living in low- and middle-income
countries.
In
countries where intravenous drug use is the biggest risk factor for HIV
transmission, as many as 7 out of 10 are co-infected. In countries where sexual
behavior is the biggest risk factor for HIV transmission, co-infection is less
common, but still a concern, with about 1 in 10 HIV sufferers being
co-infected.
Hepatitis
C is a blood-borne virus most commonly transmitted through contact with the
blood of an infected person, through sharing contaminated needles or drug use
equipment and blood transfusion. Less commonly, it is transmitted through
sexual contact or through birth to an infected mother. Hepatitis C is a much
smaller virus than HIV, so there is a lot of it even in a tiny amount of blood,
but unlike HIV, the virus can stay alive on surfaces outside the body for many
days. Hepatitis C is 10 times more infectious than HIV.
Experts
agree that co-infection makes HIV treatment more complicated. A liver damaged
from Hepatitis C may affect HIV medications negatively. Co-infection triples
the risk for liver toxicity from HIV medicines. Also, co-infection more than
triples the risk for liver disease and liver-related death.
Hepatitis
C is hugely complicated, with six different variants with further subdivisions
in each genotype. This variability has made it difficult to develop a vaccine
that would protect against all strains. However, unlike HIV, Hepatitis C can be
cured by treatment. The WHO recommends pegylated and standard interferon in
combination with ribavirin.
Persons
infected with genotypes 1 and 4 are treated for 48–72 weeks while those
infected with genotypes 2 and 3 do not have to have such intensive and
long-lasting treatment. The longer treatment durations are recommended for
persons co-infected with HIV and those with advanced fibrosis or cirrhosis.
Persons with genotype 1 infection and an extended rapid virological response are
treated with a shortened course of 24 weeks.
Thus
not only the duration of treatment for Hepatitis C for those suffering from HIV
is longer, but treatment response is also poorer. Coupled with this is the high
cost of treatment (US$ 2,000 in Egypt for 48 weeks), and the high rate of
adverse events which require regular monitoring, which prevents most patients
from receiving treatment in most low- and middle-income countries.
The
field of HCV therapeutics is however evolving rapidly. New oral drugs have the
potential to revolutionize treatment, with expected cure rates higher than 90
percent for some genotypes of the disease.
The
only deterrent is the prohibitively high price of the drugs, with a 12 week
sofosbuvir treatment costing a whopping US$84,000 in the US. At these prices,
access in low and middle-income countries is likely to be extremely limited.
Moreover the new medicines have yet to be licensed in most countries.
Generic
production of drugs for Hepatitis C can reduce the cost drastically, as has
happened with anti retrovirals for HIV. A study done at Liverpool University
shows that a 12-week course of sofosbuvir as a generic could be as low as
$68-$136. But Gourdas Choudhuri, Director and Head of Department of
Gastroenterology and Hepatobiliary Sciences at Fortis Healthcare in India,
said: “While generics are well established for chemical compounds, where
efficacy can be tested, Hepatitis C drugs have to be tested in terms of bio
efficacy too, and not just by way of chemical structures. So there will need to
be a little more reassurance from companies launching generic interferons about
their effectiveness.”
Nonetheless
all people living with HIV should be tested for Hepatitis C. A new global
resolution endorsed by all 194 member states at the 67th session of WHA in May
2014, has called for enhanced action to improve equitable access to viral
hepatitis prevention, diagnosis, and treatment and requested the WHO
Secretariat to facilitate access to affordable treatment.
During
a press conference at the 19th International AIDS Conference in 2012, Eldred
Tellis, Director of the Sankalp Rehabilitation Trust in Mumbai said that,
"It makes public health sense to link prevention efforts to HIV programs.
Prevention and harm reduction efforts for HIV and Hepatitis C with vulnerable
communities should go hand in hand. Unless this is done, HCV infections will
rise even though HIV transmission rates reduce, particularly among injecting
drug users – the most vulnerable community."
The HIV
Program is committed to increase its focus on viral hepatitis and HIV
co-infection in 2014–2015. It is hoped that the forthcoming 20th International
AIDS Conference in Melbourne will provide renewed impetuous to making timely
viral hepatitis diagnosis and treatment affordable and accessible to all those
in need of it.
Shobha
Shukla is
Managing Editor of Citizen News Service Email: shobha@citizen-news.org,
website: www.citizen-news.org).
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