The Lancet Global Health
July 28 is World Hepatitis Day—a time to “join together to make the elimination of viral hepatitis our next greatest achievement”. Hepatitis is, belatedly, beginning to nudge its way into the global awareness. Having been neglected entirely in the Millennium Development Goals, it gets a name-check alongside AIDS, tuberculosis, and malaria within Sustainable Development Goal target 3.3, and—at the World Health Assembly in May this year—the first Global Health Sector Strategy on Viral Hepatitis was endorsed. This much-anticipated strategy has a goal of eliminating viral hepatitis as a major public health threat by 2030, and particularly focuses on hepatitis B and C viruses, which cause the greatest burden worldwide.
Hepatitis B virus (HBV) is responsible for half of all deaths globally from viral hepatitis, half of all deaths from liver cancer, and a third of all deaths from liver cirrhosis. Approximately 240 million people worldwide are chronically infected with the virus, mostly in east Asia and sub-Saharan Africa, where 5–10% of the population are thought to be carriers. In such regions, most people acquire the infection as infants via vertical transmission, and it is this route that is the most dangerous. Whereas
the vast majority of individuals who acquire the disease as adults experience a brief illness and go on to clear the virus completely, those infected at birth rarely develop symptoms yet are unable to mount a suffi cient immune response to destroy the virus. It therefore remains in the body, inactive but infectious, for decades. 20–30% will experience viral reactivation and a greatly increased risk of cirrhosis or liver cancer. Treatment of active disease with antiviral drugs aims only to suppress viral
replication and prevent progression, and is thus a lifelong commitment. Ultimately, however, up to 40% of men and 15% of women with vertically acquired HBV infection will die of cirrhosis or liver cancer.
Although a vaccine exists and its coverage globally averages 84%, it is not always protective in infants whose mothers have very high viral loads, and is of no comfort to the millions currently living with this insidious infection. Screening for carrier status and regular blood tests for those found positive are therefore crucial. Yet, as Maud Lemoine and colleagues explain in an Article in this month’s issue, routine screening in one of the highest burden regions—sub-Saharan Africa—is rare. Lemoine and colleagues aimed to determine whether a community screening programme could be set up, engaged with, and successfully linked to care in The Gambia. Screening uptake was an encouraging 69% (5980 of 8170 adults), and 8% were found to be positive for hepatitis B surface antigen (HBsAg). None of those asked were aware of their status. Linkage to care at the tertiary referral centre was high (81%), but only 4% were eligible for treatment, suggesting that such a programme is likely to be feasible and not a huge burden on the health budget. A companion Article by Shevanthi Nayagam and colleagues provides further reassurance about cost-effectiveness.
In other news, a study published last month showed that tenofovir treatment for pregnant women with high viral loads could significantly reduce the chance of vertical transmission when combined with immunoglobulin prophylaxis and HBV vaccination of infants. WHO plans to update its recently released guidelines on the management of chronic hepatitis B infection to include these promising
findings. Tenofovir, then, is a key drug in both the prevention and treatment of chronic hepatitis B in resource-limited settings, yet doubts over its aff ordability remain Nayagam and colleagues’ costing analysis assumed a generic price of US$48 per person per year, yet currently only HIV programmes are eligible for this reduced price. Additionally, in many middle-income countries such as China, where the mother-to-child transmission study was done, tenofovir is not yet available in generic form:
in China it costs a punishing $2920 per person per year. WHO’s new strategy calls for 90% of people with chronic hepatitis B to know their status and for treatment coverage to reach 80% of eligible patients by 2030. One could be forgiven for feeling sceptical. But by emulating the HIV story, not least in terms of education, political lobbying, and determined action on drug and diagnostic costs, and by taking advantage of the extensive infrastructure and systems already set up for HIV screening, elimination ought not to be seen as utopian. Hepatitis B is a hidden threat both to public health and to patients themselves, but the tools exist to prevent and treat it. It’s time to put them to use.
■ The Lancet Global Health
www.thelancet.com/lancetgh Vol 4 August 2016
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