Expanding syphilis screening among pregnant women in Indonesia using the rapid dual test for syphilis & HIV with capacity building: The DUALIS Study

Mother-to-child transmission (MTCT) of syphilis, or congenital syphilis, is the second leading cause of preventable stillbirth globally, preceded only by malaria. While significant progress has been made over the past decade in preventing MTCT of HIV, the same cannot be said for syphilis. In 2016, there were more than half a million (about 661,000) cases of congenital syphilis, resulting in over 200,000 stillbirths and neonatal deaths. It is crucial that all women are provided with early syphilis screening and treatment as part of high-quality antenatal care (ANC).

Transmission of HIV and syphilis to newborns is essentially preventable through the use of affordable and reliable rapid tests to support early diagnosis and treatment in pregnancy. A single rapid test for syphilis was added to Indonesia's MTCT HIV programme in 2013. While the level of HIV testing in pregnancy has been gradually rising since that time from 2% to 27%, testing for syphilis has barely shifted from 0.45% to 0.9%. Based on an estimated syphilis prevalence rate of 1.2%, it is predicted that 10,169 stillbirth cases could potentially be averted by increasing the coverage of antenatal syphilis screening in Indonesia.

The dual test for HIV/syphilis point-of-care testing for pregnant women has been shown to be an effective and cost-saving tool for accelerating syphilis testing uptake in several low- and middle-income countries. It was approved for use in Indonesia in 2019 but is yet to be implemented. This is in part due to the low political priority given to syphilis compared with HIV, low levels of investment by the government and donors, and a paucity of evidence on the effectiveness and cost-effectiveness of the dual test in routine care in Indonesia.

For this study, we have partnered with the Indonesian Ministry of Health, WHO Indonesia, and a community NGO to evaluate the impact of the dual test with supporting elements (including capacity building the areas of screening procedures, inventory management, staff and patient engagement, data management and referrals, standard operating procedures, procurement and supply) in 4 districts of Indonesia. This cluster-randomised trial will be the first in Southeast Asia to assess the effectiveness, acceptability, cost-effectiveness, and affordability of the dual test for HIV and syphilis in routine ANC services. This intervention has the potential to contribute significantly to improved maternal and child health in Indonesia while building health system capacity to strengthen the prevention, detection, and treatment of syphilis.

HIV and syphilis screening in pregnancy is universally recommended and is essential to prevent mother-to-child transmission of HIV and syphilis, which can result in lifelong treatment, stillbirth, neonatal death and major malformation. Low levels of testing, especially for syphilis, means that many countries are not currently on track to achieve elimination by 2030. Indonesia, the fourth most populous country in the world, is among WHO's 10 priority countries for urgent intervention to reach elimination of mother-to-child transmission of HIV and syphilis. The dual test for HIV and syphilis - which uses a single rapid test to test for both infections - has the potential to increase syphilis screening in line with HIV screening in pregnancy and save costs by leveraging procurement and testing systems that are working well for HIV. The dual test for HIV and syphilis is approved and recommended for use in many low- and middle-income countries including Indonesia. Despite expectations that the test will have a catalytic effect on the elimination of MTCT of HIV and syphilis, its implementation has been extremely limited. For Indonesia, this has been attributed to low political priority, limited investment by the government and donors, and a paucity of evidence on the effectiveness and cost-effectiveness of the dual test in routine care. Our team has a unique opportunity to work with the Indonesian government and a leading implementing Indonesian agency to evaluate their expanded use. Based on a 2-arm cluster-randomised trial design, we will compare the introduction of the dual test for HIV/syphilis with capacity building elements (DT intervention) with current practice which is based on single tests for HIV/syphilis (control). The trial will be conducted in 4 districts across 2 provinces involving 750 pregnant women per arm. Our study has the potential to contribute significantly to improved maternal and child health in Indonesia while building health system capacity.