The model estimated that 69 million people were living with
HCV in 2015, 512,000 died as a result of HCV and the infection rate was 277 per
million people.
Between 2016 and 2030, 22% of all new infections will occur
in PWID, the model found.
If treatment and prevention continue at 2015 levels, the
number of people living with HCV will be almost unchanged in 2050 (58 million).
Incidence would decrease slightly by 2060 and then begin to increase again, as
would deaths due to HCV.
Improving blood safety and infection control would reduce
new infections by 58% in 2030 compared to the status quo.
Adding expanded access to needle and syringe programmes and
opioid substitution for 40% of people who inject drugs to
improved blood safety would reduce new infections by a further 7%.
In total, these two prevention interventions would avert
14.1 million new infections by 2030. They will have less impact on mortality up
to 2030 as the interval between infection and liver disease is so long.
If, on top of these measures, DAAs were
made available to everyone at the time of diagnosis, 640,000 deaths from liver
cancer or cirrhosis would be averted by 2030. The expansion of treatment would
have no effect on incidence, the model found.
Both incidence and mortality would be reduced if outreach
screening was expanded to diagnose 90% of people with HCV by 2030. Mortality
would be reduced by 61% and an additional 950,000 new infections would be averted
by 2030.
But to achieve this outcome, 51.8 million people would need
to be started on DAA treatment by 2030. After 2030, the number of people in
need of treatment would fall dramatically, so that only 12 million people would
need treatment between 2030 and 2050.
The impact of various interventions would differ from one country
to another according to local conditions. Blood safety interventions would have
an especially large impact in Egypt and Pakistan, whereas harm reduction
measures would have the greatest impact in the United States and Australia.
Infections and deaths averted are concentrated
in a small number of countries, in particular China, India, Pakistan, and
Egypt, which are the countries that contribute most to projected new infections
by 2030.
The WHO target for reducing mortality would be narrowly
missed in 2030 if the comprehensive package of all interventions was implemented
but would be achieved by 2032. The WHO target for reducing new infections would
be achieved by 2030. But the authors caution that if the effectiveness of harm
reduction interventions in preventing HCV transmission is reduced, due to the
way in which services are delivered or to high reinfection rates, the incidence
target might not be met until 2052.
“Even on the global scale where incidence is dominated by
non-PWID transmission, reducing incidence among PWID plays a key part in determining
whether elimination targets are met.”
The study authors say that the benefits of DAAs will only be
realised with an enormous increase in screening so that 90% of people with HCV
are diagnosed by 2030.
The interventions are not costed in the modelling study, but
in an accompanying comment article Stephan Wiktor, of the University of
Washington says “WHO estimated that implementing its strategy
would cost US$11·9 billion for the period 2016–21. Identifying these resources
will be particularly difficult at a time of reduced investment in global health
and a shift in focus toward universal health coverage rather than
disease-specific programmes.”