Viral load testing capacity is still weak in some of the
countries with the highest burden of HIV infection in sub-Saharan Africa and
needs urgent improvement, according to findings from a seven-country study of viral
load testing activity published in December in Mortality and Morbidity Weekly Reports (MMWR).
Three countries – Malawi, Tanzania and Uganda – did not have
the capacity to test everyone already taking antiretroviral therapy (ART) in 2016,
and the delay between testing and delivery of results averaged between 28 and
42 days in these countries.
Only two of the seven countries – South Africa and Namibia –
had the capacity to carry out at least one viral load test a year for people on ART and to deliver the result within 3-4 working days.
World Health Organization guidance recommends that everyone
taking antiretroviral treatment should receive a viral load test six months
after starting treatment and every 12 months thereafter to check that viral
suppression has been achieved and maintained.
Achieving a high level of viral suppression among people on
antiretroviral treatment is also important for achieving the third 90-90-90
goal – 90% of people on ART virally suppressed by 2020. Achieving this goal is
projected to reduce HIV transmission as well as ensure the maximum health
benefit from ART.
Data collected by Ministries of Health and the US Centers
for Disease Control (CDC) from January 2015 to July 2016 show big variations in viral
load testing capacity and coverage in seven sub-Saharan African countries.
Manufacturers Roche and Abbott were providing molecular
testing platforms used for viral load to 176 laboratories in the seven
countries by July 2016; only Uganda lacked sufficient equipment to reach its
national target for viral load tests by this time. Yet, in three countries (Malawi,
Tanzania and Uganda) it was still impossible to test everyone on ART once a
year due to lack of capacity.
National targets for viral load testing also varied. Despite
having approximately 769,000 people on treatment by the end of 2015, Tanzania’s
target aimed to carry out only 207,277 viral load tests in 2016, despite having
the capacity to carry out 412,776 tests. Under-utilisation of testing capacity
was evident in almost all countries.
The lack of speed in scaling up access was also reflected in
the proportion of people on ART who had received at least one viral load test.
In 2015 76% of people on ART in Kenya, 87% in South Africa and 91% in Namibia
received at least one viral load test, compared to 5% in Tanzania, 10% in Cote
d’Ivoire, 19% in Malawi and 23% in Uganda.
Viral suppression in 2015 ranged from 66% in Cote d’Ivoire
to 82% in Malawi, 83% in South Africa and Kenya, 87% in Namibia, 88% in
Tanzania and 91% in Uganda. Preliminary data for the first half of 2016
indicate a broadly similar pattern. Variations in viral suppression need to be
considered in the context of national policies: in Malawi, for example, viral
load testing is recommended every other year due to resource limitations, and
in other countries with lower capacity viral load testing is targeted at those
showing signs of treatment failure or reporting non-adherence.
The study also looked at the turnaround time between drawing
blood for viral load testing and the return of results. Turnaround time ranged
from less than four days in South Africa and Namibia in 2016 to between 28 and
50 days. The long delays were attributed due to equipment breakdowns, lack of
personnel and inefficient systems for specimen transport.
Delays in detecting viral rebound increase the risk that
drug resistance might develop, and delays in confirmatory viral load testing
lead to delays in switching treatment, increasing the risk of drug resistance.
The investigators conclude that more collaborative work
between donors, Ministries of Health and partners such as PEPFAR (the US President's Emergency Plan for AIDS Relief), USAID (the United States Agency for International Development) and US
CDC is needed to improve viral load testing capacity.