Antenatal Prevalence Of Syphilis Research Articles

Variations in sexual network connectivity may explain dramatic variations in sexually transmitted infection prevalence between populations and over time: a selected four-country analysis.

Background: The incidence of sexually transmitted infections (STIs) has been noted to vary dramatically between population groups and over time. Here, the hypothesis that changes in network connectivity underpin these changes is explored. Methods: The incidence/prevalence estimates of HIV, herpes simplex virus-2, syphilis, chlamydia, and gonorrhoea, as well as two markers of sexual network connectivity (partner concurrency and multiple partnering) by ethnic group and sexual orientation in Kenya, South Africa, the United Kingdom (UK) and the United States (USA) were extracted from published studies. Pearson's correlation was used to test the association between the markers of network connectivity and the incidence/prevalence of these five STIs. A literature review was performed to evaluate the possible causes of the increases and decreases in syphilis incidence over the past 60 years. Results: In each country, the five STIs were found to cluster in particular ethnic groups and sexual orientations and to be positively associated with the two markers of network connectivity. Syphilis incidence in the UK and USA was found to increase dramatically in the 1960s/1970s, decline in the 1980s and again increase in the late 1990s. These changes took place predominantly in men who have sex with men, and were preceded by corresponding changes in network connectivity. The large decline in antenatal syphilis prevalence in Kenya and South Africa in the 1990s were likewise preceded by declines in network connectivity. Conclusions: Although other explanatory variables are not controlled for, the present analysis is compatible with the hypothesis that differential network connectivity is a parsimonious explanation for variations in STI incidence over time and between populations.

Variations in sexual network connectivity may explain dramatic variations in sexually transmitted infection prevalence between populations and over time: a selected four-country analysis

Background: The incidence of sexually transmitted infections (STIs) has been noted to vary dramatically between population groups and over time. Here, the hypothesis that changes in network connectivity underpin these changes is explored. Methods: The incidence/prevalence estimates of HIV, herpes simplex virus-2, syphilis, chlamydia, and gonorrhoea, as well as two markers of sexual network connectivity (partner concurrency and multiple partnering) by ethnic group and sexual orientation in Kenya, South Africa, the United Kingdom (UK) and the United States (USA) were extracted from published studies. Pearson’s correlation was used to test the association between the markers of network connectivity and the incidence/prevalence of these five STIs. A literature review was performed to evaluate the possible causes of the increases and decreases in syphilis incidence over the past 60 years. Results: In each country, the five STIs were found to cluster in particular ethnic groups and sexual orientations and to be positively associated with the two markers of network connectivity. Syphilis incidence in the UK and USA was found to increase dramatically in the 1960s/1970s, decline in the 1980s and again increase in the late 1990s. These changes took place predominantly in men who have sex with men, and were preceded by corresponding changes in network connectivity. The large decline in antenatal syphilis prevalence in Kenya and South Africa in the 1990s were likewise preceded by declines in network connectivity. Conclusions: Although other explanatory variables are not controlled for, the present analysis is compatible with the hypothesis that differential network connectivity is a parsimonious explanation for variations in STI incidence over time and between populations.

Variations in sexual network connectivity may explain dramatic variations in sexually transmitted infection prevalence between populations and over time: a four-country analysis

Background: The incidence of sexually transmitted infections (STIs) has been noted to vary dramatically between population groups and over time. Here, the hypothesis that changes in network connectivity underpin these changes is explored. Methods: The incidence/prevalence estimates of HIV, herpes simplex virus-2, syphilis, chlamydia, and gonorrhoea, as well as two markers of sexual network connectivity (partner concurrency and multiple partnering) by ethnic group and sexual orientation in Kenya, South Africa, the United Kingdom (UK) and the United States (USA) were extracted from published studies. Pearson's correlation was used to test the association between the markers of network connectivity and the incidence/prevalence of these five STIs. A literature review was performed to evaluate the possible causes of the increases and decreases in syphilis incidence over the past 60 years. Results: In each country, the five STIs were found to cluster in particular ethnic groups and sexual orientations and to be positively associated with the two markers of network connectivity. Syphilis incidence in the UK and USA was found to increase dramatically in the 1960s/1970s, decline in the 1980s and again increase in the late 1990s. These changes took place predominantly in men who have sex with men, and were preceded by corresponding changes in network connectivity. The large decline in antenatal syphilis prevalence in Kenya and South Africa in the 1990s were likewise preceded by declines in network connectivity. Conclusions: Although other explanatory variables are not controlled for, the present analysis is compatible with the hypothesis that differential network connectivity is a parsimonious explanation for variations in STI incidence over time and between populations.

The Global Epidemiology of Syphilis in the Past Century - A Systematic Review Based on Antenatal Syphilis Prevalence.

BackgroundHow can we explain the uneven decline of syphilis around the world following the introduction of penicillin? In this paper we use antenatal syphilis prevalence (ASP) to investigate how syphilis prevalence varied worldwide in the past century, and what risk factors correlate with this variance.Methods1) A systematic review using PubMed and Google Scholar was conducted to identify countries with published data relating to ASP estimates from before 1952 until the present. Eleven countries were identified (Canada, Denmark, Finland, India, Japan, Norway, Singapore, South Africa, United States of America (USA), United Kingdom (UK) and Zimbabwe). The ASP epidemic curve for each population was depicted graphically. In South Africa and the USA, results are reported separately for the black and white populations. 2) National antenatal syphilis prevalence estimates for 1990 to 1999 and 2008 were taken from an Institute for Health Metrics and Evaluation database on the prevalence of syphilis in low risk populations compiled for the Global Burden of Diseases study and from a recent review paper respectively. National ASPs were depicted graphically and regional median ASPs were calculated for both time periods. 3) Linear regression was used to test for an association between ASP in 1990–1999 and 2008 and four risk factors (efficacy of syphilis screening/treatment, health expenditure, GDP per capita and circumcision prevalence). WHO world regions were included as potential explanatory variables.ResultsIn most populations, ASP dropped to under 1% before 1960. In Zimbabwe and black South Africans, ASP was high in the pre-penicillin period, dropped in the post-penicillin period, but then plateaued at around 6% until the end of the 20th century when ASP dropped to just above 1%. In black Americans, ASP declined in the post penicillin period, but plateaued at 3–5% thereafter. ASP was statistically significantly higher in sub-Saharan Africa in 1990–1999 and 2008 than in the other world regions (P < 0.001). On multivariate analysis in both time periods, ASP was only associated with residence in sub-Saharan Africa.ConclusionsFurther research is necessary to elucidate the reasons for the higher prevalence of syphilis in sub-Saharan Africa.

The Prevalence of Syphilis from the Early HIV Period is Correlated With Peak HIV Prevalence at a Country Level.

Could we have predicted national peak HIV based on syphilis prevalence in the 1990s? Earlier studies have shown positive correlations between various sexually transmitted infections at different population levels. In this article, we test the hypothesis that there was a residual variation in the national prevalence rates of syphilis and that these rates could predict subsequent peak HIV prevalence rates. This analysis uses linear regression to evaluate the country-level relationship between antenatal syphilis prevalence (1990-1999) and peak HIV prevalence. Antenatal syphilis data were taken from an Institute for Health Metrics and Evaluation database on the prevalence of syphilis in low-risk populations. Peak HIV prevalence was calculated based on data taken from the Global Health Observatory Data Repository of the World Health Organization. A moderately strong association is found for the 76 countries with data available (R = 0.53, P < 0.001). The association was weakened but remained significantly positive when we adjusted for the type of syphilis testing used. Syphilis prevalence in the 1990s predicted approximately 53% of the variation in peak HIV prevalence. Populations with generalized HIV epidemics had a higher prevalence of syphilis in the pre-HIV period. This finding provides additional rationale to carefully monitor sexual behavior, sexual networks, and sexually transmitted infection incidence in these populations.

Strong Country Level Correlation between Syphilis and HSV-2 Prevalence.

Background. Syphilis is curable but Herpes Simplex Virus-2 (HSV-2) is not. As a result, the prevalence of syphilis but not HSV-2 may be influenced by the efficacy of national STI screening and treatment capacity. If the prevalence of syphilis and HSV-2 is found to be correlated, then this makes it more likely that something other than differential STI treatment is responsible for variations in the prevalence of both HSV-2 and syphilis. Methods. Simple linear regression was used to evaluate the relationship between national antenatal syphilis prevalence and HSV-2 prevalence in women in two time periods: 1990–1999 and 2008. Adjustments were performed for the laboratory syphilis testing algorithm used and the prevalence of circumcision. Results. The prevalence of syphilis was positively correlated with that of HSV-2 for both time periods (adjusted correlations, 20–24-year-olds: 1990–99: R 2 = 0.54, P < 0.001; 2008: R 2 = 0.41, P < 0.001 and 40–44-year-olds: 1990–99: R 2 = 0.42, P < 0.001; 2008: R 2 = 0.49, P < 0.001). Conclusion. The prevalence of syphilis and HSV-2 is positively correlated. This could be due to a common set of risk factors underpinning both STIs.

Antenatal syphilis screening using point-of-care testing in low- and middle-income countries in Asia and Latin America: a cost-effectiveness analysis.

BackgroundUntreated syphilis in pregnancy is associated with adverse clinical outcomes to the infant. In low- and middle-income countries in Asia and Latin America, 20%-30% of women are not tested for syphilis during pregnancy. We evaluated the cost-effectiveness of increasing the coverage for antenatal syphilis screening in 11 Asian and 20 Latin American countries, using a point-of-care immunochromatographic strip (ICS) test.MethodsThe decision analytical cost-effectiveness models reported incremental costs per disability-adjusted life years (DALYs) averted from the perspectives of the national health care payer. Clinical outcomes were stillbirths, neonatal deaths, and congenital syphilis. DALYs were computed using WHO disability weights. Costs included the ICS test, three injections of benzathine penicillin, and nurse wages. Country-specific inputs included the antenatal prevalence of syphilis and the proportion of women in the antenatal care setting that are screened for syphilis infection as reported in the 2014 WHO baseline report on global sexually transmitted infection surveillance. Country-specific data on the annual number of live births, proportion of women with at least one antenatal care visit, and per capita gross national income were also included in the model.ResultsThe incremental cost/DALY averted of syphilis screening is US$53 (range: US$10-US$332; Prob<1*per capita GDP=99.71%) in Asia and US$60 (range: US$5-US$225; Prob<1*per capita GDP=99.77%) in Latin America. Universal screening may reduce the annual number of stillbirths by 20,344 and 4,270, neonatal deaths by 8,201 and 1,721, cases of congenital syphilis by 10,952 and 2,298, and avert 925,039 and 197,454 DALYs in the aggregate Asian and Latin American panel, respectively.ConclusionAntenatal syphilis screening is highly cost-effective in all the 11 Asian and 20 Latin American countries assessed. Our findings support the decision to expand syphilis screening in countries with currently low screening rates or continue national syphilis screening programs in countries with high rates.

Audit of antenatal screening for syphilis and HIV in migrant and refugee women on the Thai-Myanmar border: a descriptive study

The antenatal prevalence of syphilis and HIV/AIDS in migrants and refugees is poorly documented. The aim of this study was to audit the first year of routine syphilis screening in the same population and reassess the trends in HIV rates. From August 2012 to July 2013, 3600 pregnant women were screened for HIV (ELISA) and syphilis (VDRL with TPHA confirmation) at clinics along the Thai-Myanmar border. Seroprevalence for HIV 0.47% (95% CI 0.30-0.76) (17/3,599), and syphilis 0.39% (95% CI 0.23-0.65) (14/3,592), were low. Syphilis was significantly lower in refugees (0.07% 95% CI 0.01-0.38) (1/1,469), than in migrants (0.61% 95% CI 0.36-1.04) (13/2,123). The three active (VDRL≥1:8 and TPHA reactive) syphilis cases with VDRL titres of 1:32 were easy to counsel and treat. Women with low VDRL titres (>75% were < 1:8) and TPHA reactive results, in the absence of symptoms and both the woman and her husband having only one sexual partner in their lifetime, and the inability to determine the true cause of the positive results presented ethical difficulties for counsellors. As HIV and syphilis testing becomes available in more and more settings, the potential impact of false positive results should be considered, especially in populations with low prevalence for these diseases. This uncertainty must be considered in order to counsel patients and partners accurately and safely about the results of these tests, without exposing women to increased risk for abuse or abandonment. Our findings highlight the complexities of counselling patients about these tests and the global need for more conclusive syphilis testing strategies.

Audit of antenatal screening for syphilis and HIV in migrant and refugee women on the Thai-Myanmar border: a descriptive study

Objective: The antenatal prevalence of syphilis and HIV/AIDS in migrants and refugees is poorly documented. The aim of this study was to audit the first year of routine syphilis screening in the same population and reassess the trends in HIV rates.Methods: From August 2012 to July 2013, 3600 pregnant women were screened for HIV (ELISA) and syphilis (VDRL with TPHA confirmation) at clinics along the Thai-Myanmar border.Results: Seroprevalence for HIV 0.47% (95% CI 0.30-0.76) (17/3,599), and syphilis 0.39% (95% CI 0.23-0.65) (14/3,592), were low. Syphilis was significantly lower in refugees (0.07% 95% CI 0.01-0.38) (1/1,469), than in migrants (0.61% 95% CI 0.36-1.04) (13/2,123). The three active (VDRL≥1:8 and TPHA reactive) syphilis cases with VDRL titres of 1:32 were easy to counsel and treat. Women with low VDRL titres (>75% were < 1:8) and TPHA reactive results, in the absence of symptoms and both the woman and her husband having only one sexual partner in their lifetime, and the inability to determine the true cause of the positive results presented ethical difficulties for counsellors.Conclusion: As HIV and syphilis testing becomes available in more and more settings, the potential impact of false positive results should be considered, especially in populations with low prevalence for these diseases. This uncertainty must be considered in order to counsel patients and partners accurately and safely about the results of these tests, without exposing women to increased risk for abuse or abandonment. Our findings highlight the complexities of counselling patients about these tests and the global need for more conclusive syphilis testing strategies.

Utility of immunochromatographic assay as a rapid point of care test for screening of antenatal syphilis

Background and Objectives:Syphilis is one of the most common preventable causes of adverse effects during pregnancy. Antenatal screening prevents the delay between diagnosis and treatment there by reducing the risk of congenital syphilis. The objective of this study was to evaluate the utility of an immunochromatographic assay as a point of care test for antenatal screening of syphilis.Materials and Methods:Sera of 200 antenatal mothers were evaluated for serodiagnosis of syphilis by the venereal disease research laboratory (VDRL), Treponema pallidum hemagglutination assay (TPHA) and SD BIOLINE Syphilis 3.0 test. The performance of SD BIOLINE Syphilis 3.0 test was compared with VDRL as screening assay and TPHA as a confirmatory test.Results:The antenatal prevalence of syphilis was found to be 2% by both VDRL and TPHA. The sensitivity, specificity, positive predictive value, and the negative predictive value of SD BIOLINE Syphilis 3.0 test were 75%, 100%, 100%, and 99.45%, respectively.Conclusions:Antenatal screening and treatment of maternal syphilis are cost-effective health interventions even under the low prevalence of infection. SD BIOLINE Syphilis 3.0 test, although having less sensitivity than the existing testing strategy, can have a tremendous impact on the disease burden if used prudently for the screening of antenatal mothers in peripheral health settings.

Utility of immunochromatographic assay as a rapid point of care test for screening of antenatal syphilis.

Syphilis is one of the most common preventable causes of adverse effects during pregnancy. Antenatal screening prevents the delay between diagnosis and treatment there by reducing the risk of congenital syphilis. The objective of this study was to evaluate the utility of an immunochromatographic assay as a point of care test for antenatal screening of syphilis. Sera of 200 antenatal mothers were evaluated for serodiagnosis of syphilis by the venereal disease research laboratory (VDRL), Treponema pallidum hemagglutination assay (TPHA) and SD BIOLINE Syphilis 3.0 test. The performance of SD BIOLINE Syphilis 3.0 test was compared with VDRL as screening assay and TPHA as a confirmatory test. The antenatal prevalence of syphilis was found to be 2% by both VDRL and TPHA. The sensitivity, specificity, positive predictive value, and the negative predictive value of SD BIOLINE Syphilis 3.0 test were 75%, 100%, 100%, and 99.45%, respectively. Antenatal screening and treatment of maternal syphilis are cost-effective health interventions even under the low prevalence of infection. SD BIOLINE Syphilis 3.0 test, although having less sensitivity than the existing testing strategy, can have a tremendous impact on the disease burden if used prudently for the screening of antenatal mothers in peripheral health settings.

Low and stable rates of antenatal syphilis and HIV in migrant and refugee women on the Thai-Myanmar border: a descriptive study

Objective: The antenatal prevalence of syphilis and HIV/AIDS in migrants and refugees is poorly documented. The aim of this study was to audit the first year of routine syphilis screening in migrant and refugee women on the Thai Myanmar border.Methods: From August 2012 to July 2013, 3600 pregnant women were screened for HIV (ELISA) and syphilis (VDRL with TPHA confirmation) at clinics along the Thai-Myanmar border.Results: Seroprevalence for HIV 0.47% (95% CI 0.30-0.76) (17/3,599), and syphilis 0.39% (95% CI 0.23-0.65) (14/3,592), were low. Syphilis was significantly lower in refugees (0.07% 95% CI 0.01-0.38) (1/1,469), than in migrants (0.61% 95% CI 0.36-1.04) (13/2,123). The three active (VDRL≥1:8 and TPHA reactive) syphilis cases with VDRL titres of 1:32 were easy to counsel and treat. Women with low VDRL titres (&gt;75% were &lt; 1:8) and TPHA reactive results, in the absence of symptoms and both the woman and her husband having only one sexual partner in their lifetime, and the inability to determine the true cause of the positive results presented ethical difficulties for counsellors.Conclusion: As HIV and syphilis testing becomes available in more and more settings, the potential impact of false positive results should be considered, especially in populations with low prevalence for these diseases. This uncertainty must be considered in order to counsel patients and partners accurately and safely about the results of these tests, without exposing women to increased risk for abuse or abandonment. Our findings highlight the complexities of counselling patients about these tests and the global need for more conclusive syphilis testing strategies.

Antenatal syphilis screening using point-of-care testing in Sub-Saharan African countries: a cost-effectiveness analysis.

Untreated syphilis in pregnancy is associated with adverse clinical outcomes for the infant. Most syphilis infections occur in sub-Saharan Africa (SSA), where coverage of antenatal screening for syphilis is inadequate. Recently introduced point-of-care syphilis tests have high accuracy and demonstrate potential to increase coverage of antenatal screening. However, country-specific cost-effectiveness data for these tests are limited. The objective of this analysis was to evaluate the cost-effectiveness and budget impact of antenatal syphilis screening for 43 countries in SSA and estimate the impact of universal screening on stillbirths, neonatal deaths, congenital syphilis, and disability-adjusted life years (DALYs) averted. The decision analytic model reflected the perspective of the national health care system and was based on the sensitivity (86%) and specificity (99%) reported for the immunochromatographic strip (ICS) test. Clinical outcomes of infants born to syphilis-infected mothers on the end points of stillbirth, neonatal death, and congenital syphilis were obtained from published sources. Treatment was assumed to consist of three injections of benzathine penicillin. Country-specific inputs included the antenatal prevalence of syphilis, annual number of live births, proportion of women with at least one antenatal care visit, per capita gross national income, and estimated hourly nurse wages. In all 43 sub-Saharan African countries analyzed, syphilis screening is highly cost-effective, with an average cost/DALY averted of US$11 (range: US$2-US$48). Screening remains highly cost-effective even if the average prevalence falls from the current rate of 3.1% (range: 0.6%-14.0%) to 0.038% (range: 0.002%-0.113%). Universal antenatal screening of pregnant women in clinics may reduce the annual number of stillbirths by up to 64,000, neonatal deaths by up to 25,000, and annual incidence of congenital syphilis by up to 32,000, and avert up to 2.6 million DALYs at an estimated annual direct medical cost of US$20.8 million. Use of ICS tests for antenatal syphilis screening is highly cost-effective in SSA. Substantial reduction in DALYs can be achieved at a relatively modest budget impact. In SSA, antenatal programs should expand access to syphilis screening using the ICS test. Please see later in the article for the Editors' Summary.