Journal of Global Health: Home Journal of Global Health
Watch: Survival: The Story of Global Health - FREE
JoGH Recommends:

Peer Review Conference



Creative Commons Licence
This work is licensed under a
Creative Commons Attribution
4.0 International License
.


Shivika Trivedi, Melanie Taylor, Mary L Kamb, and Doris Chou

Abstract

Background

Countdown to 2030 (CD2030) tracks progress in the 81 countries that account for more than 90% of under-five child deaths and 95% of maternal deaths in the world. In 2017, CD2030 identified syphilis screening and treatment during antenatal care (ANC) as priority indicators for monitoring.

Methods

Country-reported data in the UNAIDS Global AIDS Monitoring System (GAM) system were used to evaluate four key syphilis indicators from CD2030 countries: (1) maternal syphilis screening and (2) treatment coverage during ANC, (3) syphilis seroprevalence among ANC attendees, and (4) national congenital syphilis (CS) case rates. A cascade analysis for CD2030 countries with coverage data for the number of women attending at least 4 antenatal care visits (ANC4), syphilis testing, seroprevalence and treatment was performed to estimate the number of CS cases that were attributable to missed opportunities for syphilis screening and treatment during antenatal care.

Results

Of 81 countries, 52 (64%) reported one or more values for CS indicators into the GAM system during 2016-2017; only 53 (65%) had maternal syphilis testing coverage, 41 (51%) had screening positivity, and 40 (49%) had treatment coverage. CS case rates were reported by 13 (16%) countries. During 2016-2017, four countries reported syphilis screening and treatment coverage of ≥95% consistent with World Health Organization (WHO) targets. Sufficient data were available for 40 (49%) of countries to construct a cascade for data years 2016 and 2017. Syphilis screening and treatment service gaps within ANC4 resulted in an estimated total of 103 648 adverse birth outcomes with 41 858 of these occurring as stillbirths among women attending ANC4 (n = 31 914 408). Women not in ANC4 (n = 25 619 784) contributed an additional 67 348 estimated adverse birth outcomes with 27 198 of these occurring as stillbirths for a total of 69 056 preventable stillbirths attributable to syphilis in these 40 countries.

Conclusion

These data and findings can serve as an initial baseline evaluation of antenatal syphilis surveillance and service coverage and can be used to guide improvement of delivery and monitoring of syphilis screening and treatment in ANC for these priority countries.


Syphilis is a leading cause of adverse pregnancy outcomes including stillbirth and neonatal death. In 2016, WHO estimated there were 988 000 maternal syphilis infections worldwide resulting in 355 000 adverse pregnancy outcomes, of which over half were stillbirths or neonatal deaths [1,2]. Both screening and treatment for syphilis during pregnancy remain sub-optimal in low- and middle-income countries despite diagnosis and prevention of maternal-to-child transmission (MTCT) of syphilis being feasible, inexpensive and cost-effective [3]. In 2007, WHO and partners launched a global initiative to eliminate congenital syphilis based on the pillars of 1) sustained political commitment and advocacy, 2) access to and quality of maternal and newborn health services; 3) universal syphilis screening for all pregnant women and treatment of women testing positive and their partners; and 4) adequate surveillance, monitoring and evaluation [4]. In 2008, ANC syphilis testing coverage, prevalence, treatment coverage, and congenital syphilis (CS) rate were added as indicators for country monitoring and reporting to the UNAIDS Global AIDS Monitoring (GAM) system [5] and are publicly reported in the WHO Global Health Observatory (GHO) [6]. This was followed by the WHO launch of the Global Guidance on Criteria and Processes for Validation of Elimination of Mother-to-Child Transmission of HIV and Syphilis in 2014. The targets countries need to achieve for elimination of MTCT of syphilis are 1) at least 95% of pregnant women attend antenatal care (ANC); 2) at least 95% of pregnant women in ANC receive syphilis screening; and 3) at least 95% of syphilis seropositive pregnant women receive adequate treatment [7].

Countdown to 2030 (CD2030) is a partnership among academic institutions, UN agencies, governments and other civil society members that provides independent analyses that aim to accelerate the achievement of the Sustainable Development Goals for ending preventable maternal, newborn and child deaths [8]. Its efforts are focused on 81 priority countries that account for more than 95% of maternal, and 90% of under-five, child deaths in the world. Moreover, CD2030 aims to utilize regional networks to build the capacity of countries to use evidence-based interventions to shape national plans and policies [9]. In 2018, CD2030 selected prevention of MTCT of syphilis as one of their initiatives and added the WHO ANC syphilis testing and treatment indicators to those which each Countdown country should monitor.

We aimed to evaluate current maternal and congenital syphilis surveillance systems in the 81 CD2030 countries through examination of two country-reported syphilis service coverage indicators: 1) percentage of pregnant women tested for syphilis and 2) percentage of seropositive pregnant women who were treated for syphilis and coverage of attendance of at least 4 antenatal care visits (ANC4). The aims of this analysis are to: describe coverage of these services in CD2030 countries towards the 95% targets required for WHO validation of CS elimination; highlight gaps in antenatal surveillance that may reflect service gaps and estimate the number of CS-associated stillbirths and other adverse birth outcomes due to service gaps within ANC and among women not attending ANC in CD2030 countries. Country use of the GAM reporting system for reporting these indicators is also described. Given the burden of maternal and neonatal disease in these countries, progress achieved in preventing CS in CD2030 countries will help to drive progress towards achieving the goals of the Global Strategy for Women, Children, and Adolescent Health [10] and the Sustainable Development Goals [8] related to improvements in maternal and newborn health.

METHODS

We utilized the Global AIDS Monitoring (GAM) surveillance system, which collates country-reported HIV/AIDS outcome and coverage indicators. Since 2008, GAM has included four key syphilis indicators: (i) maternal syphilis screening coverage and (ii) maternal syphilis treatment coverage during ANC, (iii) syphilis seroprevalence among ANC attendees, and (iv) national reported CS case rates, data which are publicly available in GHO [6]. We focused our analysis on the 81 countries prioritized by CD2030. The most recent data reported by countries during the 2-year interval from 2016 and 2017 were utilized to describe the percentage of pregnant women who were screened and treated for syphilis by country over this time period.

We applied a CS prevention cascade to estimate the number of CS cases that could be attributed to a service gap at each level of ANC service (ie, ANC attendance, syphilis testing, and treatment) similar to methods used to estimate the global burden of CS [1]. This estimate utilized those CD2030 countries with numerator and denominator data for ANC4, syphilis screening, diagnosis and treatment for data years 2016 or 2017. United Nations estimates of live births were combined with a global estimate of stillbirth to generate an estimate of total number of pregnancies for each country [11-14]. ANC was defined as attendance at a minimum of four ANC visits (ANC4) with data obtained from the WHO Department of Reproductive Health and Research ANC4+ Global Database March 2019 [15].This database contains data that are extracted from publicly available sources. Aggregate data reported from 2016-2017 among included countries were utilized to estimate the sum of women in ANC4 who were tested and not tested, the seroprevalence of syphilis in women attending ANC4, and the sum of ANC4 women who were seropositive that were treated and not treated. The number of women who were in ANC4 and not tested and the number of women not in ANC4 were multiplied by the reported maternal syphilis seroprevalence from GAM and added to the women that tested positive in ANC4 but were not treated to estimate the number of WHO-defined congenital syphilis cases attributable to a missed opportunity in ANC4 [13,16]. To estimate burden of active, transmissible syphilis, a standard syphilis test type correction factor was applied to adjust for syphilis test positivity that could be due to previously treated syphilis consistent with global CS estimation methods [1,17]. Lastly, we applied the previously derived estimate that untreated cases of maternal syphilis among women in ANC4 and not in ANC4, incurred a 52% risk of adverse birth outcomes (ABOs) and a 21% risk of stillbirth, to estimate the total number of ABOs and stillbirths that were due to CS and could have been avoided with maternal syphilis screening and treatment in 2016-2017 amongst these CD2030 countries [1,13,16].

We used the WHO case definition of congenital syphilis pertaining to infants born to pregnant women with untreated syphilis as follows [7]:

The WHO global surveillance case definition for congenital syphilis includes A live birth or fetal death at >20 weeks of gestation or >500 g (including stillbirth) born to a woman with positive syphilis serology and without adequate syphilis treatment.

We assumed reported treatment coverage reflected the WHO definition of adequate treatment to prevent congenital syphilis defined as at least one injection of 2.4 million units of benzathine penicillin given at least 30 days prior to delivery. We also evaluated the reported syphilis diagnostic test types used, with a focus on the uptake of rapid syphilis testing over the two-year period 2016-2017. For evaluation of indicators and diagnostic test type, those countries not reporting any data for 2016 to 2017, or only reporting data prior to 2016, were considered “Missing/Unknown.” Microsoft Excel (Microsoft Inc, Seattle, WA, USA) was used for all calculations with results confirmed in SPSS V. 21 (IBM Inc, Armonk, NY, USA).

RESULTS

Of 81 CD2030 countries, 53 (65%) reported one or more values for CS indicators into the GAM system during 2016-2017. Data on maternal syphilis testing coverage was provided by 52 (64%), screening positivity was reported by 49 (60%), treatment coverage was reported by 41 (51%) and syphilis test type was reported by 53 (65%) CD2030 countries. CS case rates were only reported by 13 (16%) CD2030 countries (Table 1). Of the 81 CD2030 countries, 40 (49%) reported data for all three indicators related to coverage of services (syphilis testing, test positivity, and treatment of seropositive women) during 2016 and 2017. Reported screening and treatment coverage is summarized in Table 2.

Table 1.  Syphilis screening, positivity, and treatment coverage for 81 Countdown countries 2016-2017*
Country Syphilis test type WHO region % ANC screening Year % screening % positive Year % positivity % treat Year % treat CS rate** Year CS rate
Afghanistan non-treponemal (RPR,VDRL)/treponemal (rapid tests, TPPA) Eastern Mediterranean 14.3 2017 0.3 2017 100.0 2017
Algeria not reported Africa
Angola not reported Africa
Azerbaijan not reported Europe
Bangladesh patients positive on both: non-treponemal/treponemal South East Asia 72.3 2017 0.0 2017 100.0 2017
Benin non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) Africa 3.1 2017 0.4 2017 100.0 2017
Bhutan not reported South East Asia
Bolivia (Plurinational State of) patients positive on both: non-treponemal/treponemal Americas 96.0 2017 0.9 2017 100.0 2017
Botswana non-treponemal (RPR,VDRL) Africa
Burkina Faso non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) Africa 100.0 2016 0.7 2016 100.0 2017 669 2017
Burundi not reported Africa
Cambodia treponemal (rapid tests, TPPA) Western Pacific 62.9 2017 0.0 2017 83.9 2017
Cameroon Not reported Africa
Central African Republic non-treponemal (RPR,VDRL)|patients positive on both Africa 56.1 2017 4.7 2017 97.4 2017
Chad Not reported Africa
Comoros Not reported Africa
Congo non-treponemal (RPR,VDRL) Africa 10.7 2016 0.6 2016
Côte d'Ivoire treponemal (rapid tests, TPPA) Africa
Democratic People’s Republic of Korea not reported South East Asia
Democratic Republic of the Congo non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Africa
Djibouti not reported Eastern Mediterranean
Dominican Republic non-treponemal (RPR,VDRL) Americas 42.2 2017 1.6 2017 54.1 2017
Equatorial Guinea not reported Africa
Eritrea treponemal (rapid tests, TPPA) Africa 97.2 2017 1.1 2017 100.0 2017
Ethiopia not reported Africa 44.6 2017 1.1 2017 100.0 2017
Gabon non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) Africa 31.1 2017 1.8 2017 100.0 2017
Gambia not reported Africa
Ghana non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Africa 44.6 2017 3.0 2017 91.0 2017
Guatemala non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Americas 37.1 2017 0.1 2017 47.6 2017 9.2 2017
Guinea treponemal (rapid tests, TPPA) Africa 4.8 2017 5.4 2017 100.0 2017
Guinea-Bissau not reported Africa
Guyana not reported Americas
Haiti treponemal (rapid tests, TPPA) Americas 92.5 2016 2.8 2016 89.8 2017
Honduras non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Americas 69.0 2017 0.2 2017 89.5 2017
India non-treponemal (RPR,VDRL) South East Asia 19.8 2017 0.1 2017 47.6 2017
Indonesia patients positive on both: non-treponemal/treponemal South East Asia 1.7 2017 3.2 2017 30.1 2016 1.2 2016
Iraq not reported Eastern Mediterranean
Jamaica treponemal (rapid tests, TPPA) Americas 90.0 2016 1.5 2016 70.9 2016 22.8 2016
Kenya treponemal (rapid tests, TPPA) Africa 85.7 2017 1.4 2017
Kyrgyzstan patients positive on both: non-treponemal/treponemal Europe 89.4 2017 0.0 2017 100.0 2017 3.2 2017
Lao People's Democratic Republic not reported Western Pacific 0.8 2009
Lesotho non-treponemal (RPR,VDRL) Africa 91.2 2017 2.4 2016
Liberia treponemal (rapid tests, TPPA) Africa
Madagascar treponemal (rapid tests, TPPA) Africa 28.8 2017 3.0 2017 61.0 2017
Malawi treponemal (rapid tests, TPPA) Africa 82.0 2017 1.0 2017 100.0 2016
Mali non-treponemal (RPR,VDRL) Africa 21.4 2017 6.1 2017 100.0 2016
Mauritania not reported Africa
Morocco treponemal (rapid tests, TPPA) Eastern Mediterranean 43.0 2017 1.3 2017 52.6 2017 22.5 2017
Mozambique treponemal (rapid tests, TPPA) Africa 71.9 2017 4.6 2017
Myanmar patients positive on both: non-treponemal/treponemal South East Asia 31.2 2017 0.2 2017 71.4 2017
Namibia non-treponemal (RPR,VDRL) Africa 97.9 2017 2.1 2017 6.5 2017
Nepal non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) South East Asia 0.3 2016 2016 16.7 2016 0 2017
Nicaragua non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) Americas 76.2 2017 0.1 2017 98.3 2017 3 2017
Niger non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA) Africa 19.7 2016 0.9 2016 100.0 2016
Nigeria non-treponemal (RPR,VDRL) Africa 16.1 2017 0.8 2017 74.8 2017
Pakistan not reported South East Asia
Panama non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Americas 92.7 2017 1.8 2017 83.8 2017 530 2017
Papua New Guinea treponemal (rapid tests, TPPA) Western Pacific 45.6 2017 6.8 2017 76.9 2017
Paraguay non-treponemal (RPR,VDRL)|treponemal (rapid tests, TPPA)|patients positive on both Americas 92.7 2017 1.9 2017 66.8 2017 287.6 2017
Philippines patients positive on both: non-treponemal/treponemal Western Pacific 11.7 2017 0.9 2017 43.3 2017
Rwanda not reported Africa
Senegal patients positive on both: non-treponemal/treponemal Africa 39.0 2017 2.4 2017 62.4 2017
Sierra Leone not reported Africa 8.3 2017 0.1 2017 100.0 2017
Solomon Islands non-treponemal (RPR,VDRL) Western Pacific 100.0 2017
Somalia treponemal (rapid tests, TPPA) Eastern Mediterranean 43.4 2016 1.3 2016
South Africa treponemal (rapid tests, TPPA) Africa 100.0 2017
South Sudan non-treponemal (RPR,VDRL) Africa 100.0 2017 7.6 2017
Sudan not reported Eastern Mediterranean
Suriname not reported Americas
Swaziland not reported Africa 85.2 2016 2.3 2016 2016
Tajikistan patients positive on both: non-treponemal/treponemal Europe 100.0 2016 0.0 2016 100.0 2016 3.5 2017
Timor-Leste not reported South East Asia
Togo treponemal (rapid tests, TPPA) Africa 9.3 2017 2.2 2017 100.0 2017
Turkmenistan not reported Europe
Uganda non-treponemal (RPR,VDRL) Africa 43.3 2016 2.9 2016
United Republic of Tanzania non-treponemal (RPR,VDRL) Africa 42.0 2017 1.8 2017 56.9 2016
Uzbekistan not reported Europe
Venezuela (Bolivarian Republic of) non-treponemal (RPR,VDRL) Americas 30.6 2016 2.0 2016
Yemen not reported Eastern Mediterranean
Zambia non-treponemal (RPR,VDRL)/Treponemal (rapid tests, TPPA) Africa 56.0 2017 3.5 2016 100.0 2017
Zimbabwe treponemal (rapid tests, TPPA) Africa 98.7 2017 1.9 2017 78.4 2017

ANC – antenatal care, WHO – World Health Organization, CS – Congenital syphilis, RPR – Rapid-Plasma-Reagin, VDRL – Venereal Disease Research Laboratory, TPPA – Treponema pallidum particle agglutination assay

*Country-reported data into the UNAIDS Global AIDS Monitoring System (GAM) 2016-2017 [6].

†CS rate reported as CS cases per 100 000 live births.



Table 2.  Reported performance coverage of antenatal care (ANC) syphilis screening and treatment among Countdown countries (N = 81)
ANC Syphilis Service Indicator Coverage 95% coverage*, n (%) 75%-94% coverage, n (%) 50%-74% coverage, n (%) <50% coverage, n (%) Data not reported
Syphilis screening 9 (11) 10 (12) 6 (7) 27 (33) 28 (35)
Syphilis treatment† 21 (26) 8 (10) 8 (10) 4 (5) 40 (49)

*WHO target for validation of ending mother-to-child transmission.

†Treatment coverage among those found to be syphilis test positive



Importantly, many countries reporting high treatment coverage reported very low syphilis screening coverage in ANC. Of 28 countries reporting ≥75% treatment coverage, 13 (43%) had <50% coverage for testing and an additional four (14%) had moderate (50%-74%) testing coverage. ANC4 coverage notwithstanding, four CD2030 countries (Bolivia, Burkina Faso, Eritrea, and Tajikistan) reported met the WHO targets of 95% coverage for both syphilis testing and treatment.

Analysis of the 40 CD2030 countries with data for ANC4, syphilis testing, seroprevalence and treatment was performed to build a CS prevention cascade and estimate the number of CS cases that were attributable to each service delivery gap (N = 59 784 822 pregnant women) (Figure 1, Table S1 in the Online Supplementary Document). Of 31 914 408 (53%) pregnant women receiving at least four ANC visits in these 40 countries 8 441 392 (26%) were tested for syphilis, while 23 473 016 (74%) pregnant women were in ANC4 but not tested. Based on reported maternal syphilis seroprevalence and testing and treatment coverage, an estimated 199 323 women attended ANC4 with active syphilis but were either not tested, or tested but not treated (WHO-defined CS cases). As previously estimated, 52% of untreated cases of maternal syphilis are estimated to result in ABOs including stillbirths [13,16]. Applying these estimates, the ANC4 service gaps above resulted in a total of 103 648 ABOs with 41 858 of these occurring as stillbirths among women attending ANC4 in the 40 Countdown countries with complete data for years 2016 or 2017. Women in the 40 countries that did not attend ANC4 (n = 27 870 414) contributed to the CS burden with an additional 129 516 WHO-defined CS cases with 67 348 estimated ABOs of which 27 198 of were stillbirths (Figure 1). In total, 170 996 ABOs were estimated with 69 056 occurring as stillbirths in these 40 countries. The remaining 41 Countdown countries (81-40 = 41) did not have data available for this analysis.

Figure 1.  Estimated congenital syphilis cases associated with missed opportunities for testing and treatment. Panel A. Receipt of Antenatal Care, at least four visits (ANC4). *Test type correction factor applied to percent testing positive and ANC women untested but assumed positive based on prevalence of tested proportion. Panel B. No receipt of ANC. *The same test-type correction factor applied for this proportion of women not attending ANC4 as was applied for those in ANC4. Country-reported maternal syphilis prevalence of women in ANC applied to this calculation (GAM). †The WHO global surveillance case definition for congenital syphilis is A live birth or fetal death at >20 weeks of gestation or >500 g (including stillbirth) born to a woman with positive syphilis serology and without adequate syphilis treatment” [6].
jogh-10-010504-F1


During 2016 and 2017, 53 (65%) Countdown countries reported the type(s) of syphilis diagnostic tests used for the two-year period in ANC clinics. Of these, 17 (32%) reported use of rapid treponemal-based syphilis tests; 13 (24.5%) reported use of non-treponemal diagnostic tests alone such as rapid plasmin reagin (RPR) or venereal disease research laboratory (VDRL) tests, and 23 (43%) reported use of non-treponemal diagnostic tests followed by confirmatory treponemal testing (using Treponema pallidum particle agglutination (TPPA) or Treponema pallidum haemagglutination (TPHA) assay (Table 1).

DISCUSSION

Only half of these 81 Countdown countries entered data on syphilis testing and treatment coverage into the UNAIDS GAM system in 2016 or 2017. For many countries, reported ANC syphilis services require scale-up to achieve elimination of maternal-to-child-transmission (EMTCT) by 2030. Using a pre-existing surveillance system, we were able to identify 4 countries that have reported reaching the WHO syphilis service coverage targets for validation of elimination of vertical transmission of syphilis for both testing and treatment of maternal syphilis in 2016-2017. Using a cascade-type analysis, we identified opportunities to improve syphilis testing and treatment coverage that would prevent a large number of preventable ABOs and stillbirths. These analyses demonstrate opportunities for antenatal syphilis surveillance and service improvements as part of congenital syphilis elimination efforts.

By utilizing the UNAIDS GAM system, our data can serve as an evaluation of the current state of coverage of antenatal syphilis surveillance indicators as reported by these 81 priority CD2030 countries. These data allow CD2030 to specifically tailor their congenital syphilis prevention and elimination efforts. Rather than creating a new surveillance system, efforts can be centered on improving reporting and analysis of data reported to UNAIDS GAM, and evaluating reporting and coverage trends over time, as well as surveillance gaps. For this to happen, more CD2030 countries could be supported to report ANC syphilis indicator data to GAM, and those that are now reporting could do so more completely and consistently [5].

It is important to note that the collective targets for ANC coverage, antenatal syphilis testing and antenatal syphilis treatment must be met to achieve the goal of elimination of CS, and women must first have access to, and attend, ANC in order to take advantage of these preventive services. For this reason, reported coverage of each indicator must be interpreted in the context of the other indicators. Nearly, one-third of CD2030 countries (25, 30.9%) reported >75% maternal syphilis treatment coverage, however, many of these countries had very low testing coverage. These countries may be doing a good job at treating pregnant women who are seropositive for syphilis, but they are not doing a good job at screening this population, and thus likely have not seen improvements in CS rates.

As the targets for elimination of CS are predicated on women accessing ANC, the cascade analysis of missed opportunities for prevention demonstrates how service gaps at each level contribute to the total missed opportunities for intervention and CS rate reduction. Using the GAM data for 2016-2017, we were able to estimate the ABOs and stillbirths that are due to missed opportunities within and outside of ANC, data which can be used to support surveillance and service improvements. Moreover, it is important to note that this estimate likely substantially underestimates the number of ABOs and stillbirths attributable to limited syphilis testing and treatment coverage in the CD2030 countries as our cascade analysis was limited to only 40 of 81 CD2030 countries with complete data for each indicator. It is plausible that even with high coverage of syphilis testing, treatment rates may be lower, even in countries that have prioritized efforts to eliminate congenital syphilis, due to shortages of benzathine penicillin during this same time period. Of note, 29 out of 41 countries with shortages in benzathine penicillin between 2014 and 2016 were also CD2030 countries which may explain lower treatment coverage for some [18]. Lastly, it is possible that by virtue of collecting and reporting on these data, these CD2030 countries may in fact, represent the highest coverage for these indicators, which would mean our results grossly underestimate the reality that exists in the remaining CD2030 countries.

The methods used for estimation of CS cases, ABOs and stillbirths in this analysis were similar to those used for global estimation of CS [1]. This analysis differs from that of the recent global CS estimation in that the data input for ANC coverage here was ANC4 whereas ANC1 (at least one ANC visit) was used for the 2016 global CS estimates. The use of ANC4 reflects the WHO modification of the minimum number of ANC visits to 8 contacts in order to achieve effective care during pregnancy, which is now the ANC coverage indicator monitored for CD2030 countries [19]. Data sources for live births were different. Modelling methods used for global estimates of maternal syphilis prevalence were not used here. We assumed reported treatment was adequate for CS prevention and did not estimate residual CS cases occurring due to inadequate or late treatment. Thus, the recently reported 2016 WHO estimates of CS that include these countries cannot be compared to estimates presented here. We readily acknowledge that some countries may collect ANC syphilis screening and treatment coverage but not report into the GAM system. Considering the countries that do utilize GAM, further analyses are needed to definitively identify and address the underlying circumstances to explain high treatment coverage rates in the face of low coverage of testing. For a myriad of reasons, many women do not access ANC. Within ANC, syphilis screening may not be offered due to limited or no testing capacity or it may be offered but at an additional cost. Stock-outs of syphilis test kits and reagents are common, and the need to present to an off-site laboratory for testing may be an additional hurdle. Women may be lost to follow up for treatment after diagnosis of syphilis is made for several reasons. This may include cases where women need to return to a laboratory to obtain results, require outside treatment referrals, have additional costs to receive treatment. Countries may face penicillin shortages resulting in no treatment or providers may use alternative regimens which are not recommended or lack effectiveness data for prevention of CS [18]. Lastly, even those women who are screened and appropriately treated for syphilis remain at risk for re-infection if their partners are not appropriately treated.

Through evaluation of diagnostic test type, it is possible to highlight the use and benefits of rapid syphilis testing in low- and middle-income countries. Among countries reporting test type, approximately one-third (32%) use rapid syphilis tests during ANC. Rapid syphilis testing has the advantage of providing same day results with the opportunity to treat at the time of diagnosis. Utilization of rapid syphilis testing could allow countries to both increase the number of pregnant females screened, while also increasing their treatment coverage within ANC settings where service coverage can be evaluated and monitored. Two rapid dual HIV/syphilis test kits have now received WHO pre-qualification [20] Use of these test kits can result in immediate scale up of syphilis screening alongside that of HIV with the option of same visit treatment for women testing positive for syphilis [21].

These data and this analysis have limitations. Data reporting into the GAM system were inconsistent over the years, some data were implausible, and there are numerous CD2030 countries that did not provide any data into this system. Additional data sources for maternal syphilis screening and treatment of pregnant women may be available but not included in the UNAIDS GAM reporting. It is difficult to know if only the surveillance system is lacking in these countries, or if the coverage of these indicators is also lacking. Same day testing and treatment through the use of point-of-care rapid syphilis tests among women attending only one ANC visit is possible and thus our results could be overestimates for countries where this service is in place. Our analysis of these data are purely descriptive in nature.

These 81 CD2030 countries account for more than 95% of maternal and 90% of under-five child mortality in the world [22]. As a result, uptake of effective syphilis interventions in pregnancy by these countries is well placed to decrease overall levels of preventable, adverse maternal and neonatal outcomes, and eliminate congenital syphilis. To our knowledge this study represents the first evaluation of antenatal syphilis screening and treatment coverage in the 81 CD2030 countries using data reported into the UNAIDS GAM system, as well as the first estimate of ABOs and stillbirths attributable to these service gaps in CD2030 countries where data are available. We encourage countries to improve ANC syphilis screening and treatment coverage and to prioritize the use of the UNAIDS GAM system to capture and monitor progress towards EMTCT [7]. Information on the downstream effects of missed opportunities to screen and treat women for syphilis during ANC provide a rich source of evidence for scale up [23,24].

Additional material
Acknowledgments

The authors would like to acknowledge Ann-Beth Moller for her assistance in data collection.

Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the World Health Organization, or the U.S. Centers for Disease Control and Prevention.

Notes

[1] Funding: The project was funded by the World Health Organization, Department of Reproductive Health and Research, and Human Reproduction Program STI program and furthermore supported by a cooperative agreement from the US Centers for Disease Control and Prevention in support of strengthening STI surveillance and eliminating congenital syphilis.

[2] Authorship contributions: ST, MK, DC, and MT conceived the analysis, MT and DC collected data, ST and MT performed the data analysis, ST, MK, DC, and MT wrote the manuscript. All authors contributed to the final version of the manuscript.

[3] Competing interests: The authors completed the ICMJE Unified Competing Interest form (available upon request from the corresponding author), and declare no conflicts of interest.

REFERENCES

[1] EL Korenromp, J Rowley, M Alonso, M Brito de Mello, NS Wijesooriya, and SG Mahiané. Global burden of maternal and congenital syphilis and associated adverse birth outcomes – estimates for 2016 and progress since 2012. PLoS One.. 2019;;14::e1002473.

[2] World Health Organization. Report on global sexually transmitted infection surveillance. Geneva: WHO; 2018.

[3] JG Kahn, A Jiwani, GB Gomez, SJ Hawkes, HW Chesson, and N Broutet. The cost and cost-effectiveness of scaling up screening and treatment of syphilis in pregnancy: a model. PLoS One.. 2014;;9::e87510. DOI: 10.1371/journal.pone.0087510. [24489931]

[4] World Health Organization. The global elimination of congenital syphilis: rationale and strategy for action. Geneva: WHO; 2007.

[5] UNAIDS. Global AIDS Monitoring 2018: Indicators for monitoring the 2016 United Nations Political Declaration on Ending AIDS. Geneva: UNAIDS; 2017.

[6] World Health Organization. Global Health Observatory. Available: https://apps.who.int/gho/data/node.main.A1357STI?lang=en). Accessed: 18 February 2019.

[7] World Health Organization. Global guidance on criteria and processes for validation: Elimination of Mother-to-Child Transmission of HIV and Syphilis. Geneva: WHO; 2017.

[8] United Nations. Sustainable Development Goals. Available: https://sustainabledevelopment.un.org/?menu=1300. Accessed: 18 February 2019.

[9] C Victora, J Requejo, T Boerma, A Amouzou, ZA Bhutta, and RE Black. Countdown to 2030 for reproductive, maternal, newborn, child, and adolescent health and nutrition. Lancet Glob Health.. 2016;;4::e775--6. . DOI: 10.1016/S2214-109X(16)30204-2. [27650656]

[10] World Health Organization. Global strategy for women's children's and adolescents' health. Available: https://www.who.int/life-course/publications/global-strategy-2016-2030/en/. Accessed: 18 March 2019.

[11] UNDATA. Annual number of births (Births). Available: http://data.un.org/Data.aspx?d=SOWC&f=inID%3A75. Accessed 18 March 2019.

[12] UNSTATS. UN Statistical Division, live births, deaths, and infant deaths, latest available year (2004-2018). Available: https://unstats.un.org/unsd/demographic-social/products/vitstats/seratab3.pdf. Accessed: 18 March 2019.

[13] H Blencowe, S Cousens, M Kamb, S Berman, and JE Lawn. Lives Saved Tool supplement detection and treatment of syphilis in pregnancy to reduce syphilis related stillbirths and neonatal mortality. BMC Public Health.. 2011;;11: Suppl 3:S9 . DOI: 10.1186/1471-2458-11-S3-S9. [21501460]

[14] H Blencowe, S Cousens, FB Jassir, L Say, D Chou, and C Mathers. National, regional, and worldwide estimates of stillbirth rates in 2015, with trends from 2000: a systematic analysis. Lancet Glob Health.. 2016;;4::e98--108. . DOI: 10.1016/S2214-109X(15)00275-2. [26795602]

[15] World Health Organization. Sexual and Reproductive Health indicators database. Department of Reproductive Health and Research.

[16] G Gomez, LM Newman, J Mark, N Broutet, and SJ Hawkes. Untreated maternal syphilis and adverse outcomes of pregnancy: a systematic review and meta-analysis. Bull World Health Organ.. 2013;;91::217--26. . DOI: 10.2471/BLT.12.107623. [23476094]

[17] DC Ham, L Newman, NS Wijesooriya, and M Kamb. Improving global estimates of syphilis in pregnancy by diagnostic test type: A systematic review and meta-analysis. Int J Gynaecol Obstet.. 2015;;130::S10--4. . DOI: 10.1016/j.ijgo.2015.04.012. [25963909]

[18] S Nurse-Findlay, MM Taylor, M Savage, MB Mello, S Saliyou, and M Lavayen. Supply, demand, and shortages of benzathine penicillin for treatment of syphilis: A market assessment. PLoS Med.. 2017;;14::e1002473. DOI: 10.1371/journal.pmed.1002473. [29281619]

[19] World Health Organization. WHO recommendations on antenatal care of a positive pregnancy experience. Geneva: WHO; 2016.

[20] World Health Organization. In vitro diagnostics and laboratory technology. Public reports of WHO prequalified IVDs. Available: https://www.who.int/diagnostics_laboratory/evaluations/pq-list/hiv_syphilis. Accessed: 18 March 2019.

[21] A Storey, F Seghers, L Pyne-Mercier, RW Peeling, MN Owiredu, and MM Taylor. Syphilis diagnosis and treatment during antenatal care: The potential catalytic impact of the dual HIV/Syphilis Rapid Diagnostic Test. Lancet Glob Health.. 2019;;7::e1006--8. . DOI: 10.1016/S2214-109X(19)30248-7. [31303285]

[22] Countdown to 2030. Countdown to 2030: Women's, Children's and Adolescent Health, homepage. Available: http://countdown2030.org/about/data. Assessed: 3 April 2019.

[23] U Baker, M Okuga, P Waiswa, F Manzi, S Peterson, and C Hanson. Bottlenecks in the implementation of essential screening tests in antenatal care: Syphilis, HIV, and anemia testing in rural Tanzania and Uganda. Int J Gynaecol Obstet.. 2015;;130::S43--50. . DOI: 10.1016/j.ijgo.2015.04.017. [26054252]

[24] F Althabe, E Chomba, AK Tshefu, E Banda, M Belizán, and E Bergel. A multifaceted intervention to improve syphilis screening and treatment in pregnant women in Kinshasa, Democratic Republic of the Congo and in Lusaka, Zambia: a cluster randomised controlled trial. Lancet Glob Health.. 2019;;7::e655--63. . DOI: 10.1016/S2214-109X(19)30075-0. [30910531]



Journal of Global Health (ISSN 2047-2986), Edinburgh University Global Health Society
Designed by