In 2007 the World Health Organization (WHO) agreed a strategy to eliminate congenital syphilis (also known as mother-to-child transmission, or MTCT, of syphilis). In 2016 WHO endorsed a more inclusive strategy as a pathway towards the goal of eliminating sexually transmitted infections, including congenital syphilis, as a public health threat by 2030. The strategy to eliminate congenital syphilis relies heavily on high coverage of antenatal care, screening for maternal syphilis, and treatment of women with syphilis and their partners—health services that may be at risk due to COVID-19.
The COVID-19 pandemic is having indirect deleterious effects on maternal and child health. In many low- and middle-income countries (LMICs), it is limiting access to antenatal care and poses considerable challenges for eliminating congenital syphilis, and achieving universal health coverage more generally. In this blog, we argue that a review of the present strategy to eliminate congenital syphilis is urgently needed.
The continuing neglect of congenital syphilis
Almost 20 years ago we wrote that congenital syphilis was forgotten but not gone. We were therefore encouraged when, several years later, the WHO set out the rationale and strategy for the global elimination of congenital syphilis.
WHO’s elimination strategy rests on four pillars:
- sustained political commitment and advocacy;
- access to, and quality of, maternal and newborn health services;
- screening and treating pregnant women and their partners; and
- surveillance, monitoring, and evaluation systems.
These are all necessary but probably not sufficient as the strategy is essentially dependent on one core intervention: screening and treating large numbers of pregnant women and their partners for syphilis. The strategy requires coverage of syphilis testing of pregnant women of ≥95 percent and treatment coverage of syphilis-seropositive pregnant women of ≥95 percent. However, despite significant advances in point-of-care tests for syphilis and the fact that antenatal screening and treatment of maternal syphilis is widely considered excellent value for money, coverage of maternal syphilis screening and treatment remains woefully below the levels needed to eliminate congenital syphilis in most countries.
Since first announcing its strategy to eliminate congenital syphilis, WHO has produced many related policies and technical advice, including detailed guidance on criteria and processes for the validation of MTCT of HIV and syphilis. All WHO regions have approved strategies to eliminate MTCT of syphilis and HIV. And there have been some success stories, including several small Caribbean states but also Cuba, Sri Lanka, Armenia, Belarus, Thailand, and the Maldives.
However, congenital syphilis continues to be a neglected, significant, and stubborn problem particularly in many LMICs and especially in sub-Saharan Africa. Before the COVID-19 pandemic, estimates suggest that annually there were almost 700,000 babies and pregnancies affected by syphilis resulting in adverse birth outcomes (babies born with congenital syphilis, early fetal deaths and stillbirths, neonatal deaths, and preterm or low birth weight babies). Serious problems with the antenatal screening and treatment of women with maternal syphilis in Africa have been documented, and partner notification and follow-up seldom occurs. A recent evaluation of the coverage of maternal screening and treatment for syphilis in the 81 “countdown to 2030” countries which account for more than 95 percent of maternal and 90 percent of under-five child mortality in the world, found only half of these countries entered data on syphilis testing and treatment coverage into the UNAIDS Global Aids Monitoring system. Only 53 countries (65 percent) reported maternal syphilis testing coverage, 49 (60 percent) noted screening positivity, and 41 (51 percent) recorded treatment coverage.
Beyond LMICs, syphilis is re-emerging as a public health concern in more affluent countries. Until recently the syphilis epidemic in these countries had been primarily attributable to increased cases among men and, specifically, among gay, bisexual, and other men who have sex with men. However, over the last five years, cases among women have increased substantially and is of particular concern because it is associated with a striking concurrent increase in congenital syphilis.
With increasing syphilis generally, and specifically among pregnant women in Europe and the US, there has been a reassessment of the contributing factors and options for a response. This has recognised that risk factors for syphilis are complex and consequently interventions need to involve medical and public health fields and biomedical researchers.
COVID-19 and syphilis: What do we know?
Recently, we have written about the harmful effects that the COVID-19 pandemic is having on essential health services, including maternal and child health, and particularly in limiting access to antenatal care. Early estimates suggested the virus will lead to an increase in stillbirths and neonatal deaths due to maternal syphilis caused by disruptions to health care including antenatal care. While it is difficult to generalise about changes in maternal health services, disruptions have been seen in several countries. For example, the number of women in 2020 who have attended four antenatal visits fell in Liberia (by 18 percent in April), and in Nigeria (by 16 percent). Specifically, in Africa major interruptions to reproductive health care have occurred, particularly in countries with high birth rates (such as Uganda, Nigeria and Ethiopia) and in some countries declines in utilisation of antenatal care of up to 25 percent have been reported. UNICEF has noted that due to COVID-19, women are experiencing severe difficulties accessing these services. While benzathine penicillin is the sole effective antibiotic in the treatment of maternal and congenital syphilis, existing shortages of it have worsened due to disruptions in international supply chains resulting from the COVID-19 pandemic.
Time for a rethink?
There were problems with the WHO strategy even before the COVID-19 pandemic, and reservations have been raised about the feasibility of the existing strategy to eliminate congenital syphilis. In 2017, a WHO meeting in Geneva reviewed progress in the Strategy for the Global Elimination of Congenital Syphilis 10 years after its launch in 2007. As noted by some public health researchers, “the general consensus at the meeting was that little progress has been made over the past decade.” However, it was concluded that the strategy was appropriate and the antenatal care interventions identified earlier, should simply be strengthened and their effective coverage increased. It was agreed this should be accompanied by more focused advocacy and surveillance. WHO continues to consider their strategy is robust and feasible, and is adding elimination of hepatitis B with a move to “triple elimination.”
The COVID-19 pandemic is having serious indirect effects on maternal and child health. There is an urgent need to reconsider whether the present WHO elimination strategy for MTCT of syphilis, and specifically in LMICs, is still fit for purpose in a (post-)COVID-19 world. We need a strategy to control maternal syphilis that is more flexible, locally directed and adapted—as we argued in the past—and takes into account the wider syphilis epidemic.
Focus on what is attainable and not what is ideal
Countries should emphasise what is attainable and not what is ideal. This should follow the classic approach to prevention and consist of antenatal screening and treatment but also strengthening of health services for contact tracing of sexual partners, and education of the public and health professionals on aspects of control. These should remain the basis for syphilis control and include interventions which not only target pregnant women but also strengthen reproductive health services with a focus on awareness of and testing for syphilis when adults present for outpatient care, adequate supplies of benzathine penicillin and emphasise contact tracing of men and women diagnosed with syphilis. At a global level given the present attention to new vaccines, further consideration could be given to the development of a vaccine against syphilis.
- WHO’s global elimination of congenital syphilis strategy has made limited progress over the past 10 to 20 years. While on paper congenital syphilis may no longer be forgotten, evidence suggests it nevertheless continues to be a serious public health problem.
- The WHO elimination strategy has relied almost entirely on very high coverage of antenatal screening and treatment of maternal syphilis which has proven to be beyond the reach of all but a handful of countries.
- COVID-19 has complicated what was already a challenging public health problem. It has disrupted the delivery of antenatal screening and treatment services.
- As countries monitor the effects of COVID-19 on these services, and devise ways to mitigate these effects, there’s an opportunity at the global level to review the present elimination strategy. More feasible plans must be identified to control congenital syphilis which go beyond a reliance on antenatal care.
Godfrey Walker is a retired public health physician. His last position before retirement was Director of UNFPA’s Regional Office for Eastern Europe and Central Asia. He also worked for the World Health Organization between 1987-1997.
CGD blog posts reflect the views of the authors, drawing on prior research and experience in their areas of expertise. CGD is a nonpartisan, independent organization and does not take institutional positions.