Abstract

Objective:

to describe the epidemiological profile of congenital syphilis (CS) in Tocantins, from 2007 to 2015.

Methods:

this was a cross-sectional descriptive study conducted with data from the Notifiable Health Conditions Information System (SINAN) and the Live Birth Information System (SINASC).

Results:

1,029 CS cases were reported; mean CS incidence was 4.6/1,000 Live Births (LB), increasing from 3.1/1,000 LB in 2007 to 9.8/1,000 LB in 2015 (increase of 216.1%); municipalities located in the central and northern regions of the state had the highest rates; the majority of mothers of newborn babies were 15-24 years old, had elementary school education, started prenatal care in the third trimester of pregnancy, and received inadequate prenatal care.

Conclusion:

high occurrence of congenital syphilis in Tocantins requires immediate intensification of CS surveillance and improved prenatal care quality, especially in municipalities with higher incidence.

Keywords:
Syphilis, Congenital; Prenatal Care; Epidemiology, Descriptive

Introduction

Congenital syphilis (CS) is a Public Health problem, even though it can be prevented: control of mother-to-child syphilis transmission is feasible and includes diagnostic tests and effective low-cost treatment.¹1. Organização Mundial da Saúde. Eliminação mundial da sífilis congênita: fundamento lógico e estratégia para ação [Internet]. Genebra: Organização Mundial da Saúde; 2008[citado 2017 out 25]. 38 p. Disponível em: Disponível em: https://apps.who.int/iris/bitstream/handle/10665/43782/9789248595851_por.pdf
https://apps.who.int/iris/bitstream/hand... Infection of pregnant women by Treponema pallidum, the etiological agent of syphilis, results in unfavorable outcomes and serious perinatal sequelae such as deafness, blindness, mental disability, premature childbirth and miscarriage, among others.

Since 2010, occurrence of CS has been growing in Latin America and the Caribbean. Estimates indicate that 22,400 babies were born with syphilis in the region in 2015.²2. Organização Pan-Americana da Saúde. Redução da transmissão materno-infantil de HIV e sífilis desacelera na América Latina e no Caribe, alerta OPAS [Internet]. Brasília: Organização Pan-Americana da Saúde; 2017 [citado 2017 out 6]. Disponível em: Disponível em: https://www.paho.org/bra/index.php?option=com_content&view=article&id=5425
https://www.paho.org/bra/index.php?optio... In Brazil, in 2016, the acquired syphilis detection rate was 42.5/100,000 inhabitants, the incidence rate among pregnant women was 12.4/1,000 live births (LB) and congenital syphilis incidence was 6.8/1,000 LB.³3. Ministério da Saúde (BR). Secretaria de Vigilância em Saúde. Sífilis 2017. Bol Epidemiol [Internet]. 2017 [citado 2018 dez 10];48(36). Disponível em: http://www.aids.gov.br/pt-br/pub/2017/boletim-epidemiologico-de-sifilis-2017

The Brazilian Pact for Health includes actions aimed at overcoming difficulties in controlling syphilis, such as lack of treating partners⁴4. Ministério da Saúde (BR). Secretaria de Vigilância em Saúde. Departamento de DST, Aids e Hepatites Virais. Protocolo clínico e diretrizes terapêuticas para atenção integral às pessoas com infecções sexualmente transmissíveis [Internet]. Brasília: Ministério da Saúde; 2015 [citado 2020 mar 2]. 120 p. Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/protocolo_clinico_diretrizes_terapeutica_atencao_integral_pessoas_infeccoes_sexualmente_transmissiveis.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... and the predominance of pregnant women with incomplete prenatal health care.⁵5. Ministério da Saúde (BR). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Atenção ao pré-natal de baixo risco. Brasília: Ministério da Saúde ; 2012 [citado 2020 mar 2]. 318 p. (Cadernos de Atenção Básica n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... Between 2010 and 2016, 1,021 CS cases were notified in the state of Tocantins, accounting for 1.04% of total cases detected in Brazil in the same period. In 2016, the incident rate of the disease was 9.9/1,000 LB, this being higher than the country’s mean rate of 6.8/1,000 LB.⁶6. Ministério da Saúde (BR). Secretaria de Vigilância em Saúde. Sífilis 2016. Bol Epidemiol [Internet]. 2017 [citado 2018 dez 10];47(35). Disponível em: Disponível em: http://www.aids.gov.br/publicacao/2016/boletim-epidemiologico-de-sifilis
http://www.aids.gov.br/publicacao/2016/b... It is important to monitor this indicator and to raise the awareness of health service managers as to the need for interventions intended to enhance congenital syphilis prevention and control, especially with regard to the quality of prenatal care.

The objective of this study was to describe the epidemiological profile of congenital syphilis in the state of Tocantins, Brazil, between 2007 and 2015.

Methods

This is a descriptive study relating to the period 2007-2015. Tocantins is located in the southeast of Brazil’s Northern region and covers an area of approximately 277,621km². In 2010, the state had 1,383,445 inhab., and demographic density of 4.98 inhab./km²2. Organização Pan-Americana da Saúde. Redução da transmissão materno-infantil de HIV e sífilis desacelera na América Latina e no Caribe, alerta OPAS [Internet]. Brasília: Organização Pan-Americana da Saúde; 2017 [citado 2017 out 6]. Disponível em: Disponível em: https://www.paho.org/bra/index.php?option=com_content&view=article&id=5425
https://www.paho.org/bra/index.php?optio... .⁷7. Instituto Brasileiro de Geografia e Estatística. Estados@ [Internet]. Rio de Janeiro: Instituto Brasileiro de Geografia e Estatística; 2010 [citado 2020 mar 2]. Disponível em: Disponível em: http://www.ibge.gov.br/estadosat/perfil
http://www.ibge.gov.br/estadosat/perfil...

The study population was comprised of live births in the period 2007-2015. The Notifiable Health Conditions Information System (SINAN) and the Live Birth Information System (SINASC) were the study’s data sources.

The following variables were analyzed:

a) Variables relating to pregnant women

b) Variables relating to partners

c) Variables relating to the newborn

Adequacy of care provision was based on the criteria established by the Ministry of Health.⁶6. Ministério da Saúde (BR). Secretaria de Vigilância em Saúde. Sífilis 2016. Bol Epidemiol [Internet]. 2017 [citado 2018 dez 10];47(35). Disponível em: Disponível em: http://www.aids.gov.br/publicacao/2016/boletim-epidemiologico-de-sifilis
http://www.aids.gov.br/publicacao/2016/b... The proportions in each stratum of the variables of interest were calculated excluding cases with missing information.

Annual CS incidence coefficients per 1,000 LB between 2007 and 2015 were calculated. Cumulative mean incidence coefficients per municipality for the period were used in the analysis of spatial distribution. This indicator was represented on a map of the state of Tocantins, prepared with the aid of TabWin 4.14.

The study project was approved by the Tocantins State Health Department, as per Ordinance No. 796/2014, and was approved by the Federal University of Bahia Public Health Institute Research Ethics Committee (CEP/ISC/UFBA): Opinion No. 1.990.883, dated March 28^th 2017.

Results

Between 2007 and 2015, 1,029 CS cases were notified in the state of Tocantins, corresponding to a mean annual incidence rate of 4.6/1,000 LB. During the period, this indicator increased from 3.1/1,000 (2007) to 9.8/1,000 LB (2015), representing an increase of 216.1%. This increase was not linear, given that between 2007 and 2009, CS incidence reduced from 3.1 to 2.6%, while between 2011 and 2015 it increased by 157.9%, from 3.8 to 9.8%.

The mothers of the majority of newborns with CS were aged 15-24 (57.6%) and 25-34 years old (34.2%), had elementary education (75.2%), lived in the urban zone (91.4%) and were of brown race/skin/color (86.3%). Among the 891 (89.1%) mothers who had prenatal care, 21.2% started care in the 1^st trimester of pregnancy, 33.0% in the 2^nd and 45.8% in the 3^rd trimester. It was found that 50.8% of maternal syphilis cases were diagnosed during prenatal care and 41.7% at the time of childbirth/curettage; and that for 83.9% of the 670 pregnant women submitted to treatment, treatment was considered to be inadequate. Mothers whose partners were treated or not treated for syphilis, corresponded to 17.0% and 83.0% of the 943 reported cases, respectively (Table 1). Information was unknown/not recorded in relation to 34.9% of the ‘adequacy of maternal treatment for syphilis’ variable; with regard to the other variables, this percentage varied between 0.4% for race/skin color and 10.2% for schooling.

With regard to reported cases of newborns with CS, 86.7% were tested using peripheral blood VDRL and 39.4% using cerebrospinal fluid VDRL, whereby 86.2% and 5.9% were reactive, respectively. Among those indicating cerebrospinal fluid change, 43.5% were examined and change was found in 2.1% of the cases. In relation to clinical diagnosis, 86.9% were asymptomatic; and for the 859 for whom information about treatment was available, the most used drug (73.8%) was crystalline penicillin (Table 2).

Of the 139 municipalities existing in Tocantins, two - one in the central region and the other in the northern region of the state - had mean incidence ranging from 5.0 to 11.0/1,000 LB. A further two municipalities, also located in the central region, had incidence ranging from 1.0 to 5.0/1,000 LB. In the majority of the municipalities (74.8%), the incidence rate was up to 1.0/1,000 LB; in the remaining municipalities (22.3%), there were no records of the disease (Figure 1).

Discussion

Evidence was found of intense increase in CS incidence in the state of Tocantins between 2007 and 2015. The majority of mothers were of childbearing age, had low levels of schooling, were of brown race/skin color, began their prenatal appointments in the 3^rd term of pregnancy and approximately half of them received diagnosis of syphilis during those appointments. Treatment was inadequate for over 80% of pregnant women and a similar proportion was found regarding treatment of their partners.

The growth in CS incidence in the state may result both from an increase in the real number of cases and also from improved structuring of the health service network. Considering the expansion of the Family Health Strategy and adherence to the Stork Network (Rede Cegonha), these Public Health initiatives may possibly have contributed to improved case notification. It is noteworthy that CS has been seen to have increased in Brazil as a whole,⁵5. Ministério da Saúde (BR). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Atenção ao pré-natal de baixo risco. Brasília: Ministério da Saúde ; 2012 [citado 2020 mar 2]. 318 p. (Cadernos de Atenção Básica n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... suggesting that progress achieved through the Family Health Strategy and the Stork Network is increasing sensitivity with regard to CS detection, although such progress has not shown itself to be sufficient to prevent infections during pregnancy or even early detection - and treatment - of pregnant women and their partners in the sense of avoiding new CS cases.

As in other studies,⁸8. Ximenes IPE, Moura ERF, Freitas GL, Oliveira NC. Incidência e controle da sífilis congênita no Ceará. Rev RENE [Internet]. 2008 jul-set [citado 2020 mar 2];9(3):74-80. Disponível em: Disponível em: http://www.periodicos.ufc.br/rene/article/view/5067/3716
http://www.periodicos.ufc.br/rene/articl... ^,99. Organização Pan-Americana da Saúde. Plano estratégico regional para HIV/AIDS e IST 2006-2015: avaliação intermediária [Internet]. CSP28/INF/3 (Port.). S.l.: Organização Pan-Americana da Saúde; 2005 [citado 2012 out 16]. p. 20-26. Disponível em: Disponível em: https://iris.paho.org/bitstream/handle/10665.2/34233/CSP28-INF-3-D-p.pdf?sequence=19&isAllowed=y
https://iris.paho.org/bitstream/handle/1... the majority of pregnant women had prenatal health care, and this must have contributed to improving detection of syphilis. Some authors have found low percentages of pregnant women starting prenatal care late;¹⁰10. Oliveira LR, Costa MCN, Barreto FR, Pereira SM, Dourado I, Teixeira MG. Evaluation of preventative and control measures for congenital syphilis in State of Mato Grosso. Rev Soc Bras Med Trop [Internet]. 2014 maio-jun [citado 2020 mar 2];47(3):334-40. Disponível em: Disponível em: https://doi.org/10.1590/0037-8682-0030-2014
https://doi.org/10.1590/0037-8682-0030-2... ^,1111. Domingues RMSM, Saracen V, Hartz ZMA, Leal MC. Sífilis congênita: evento sentinela da qualidade da assistência pré-natal. Rev Saúde Pública [Internet]. 2013 fev [citado 2020 mar 2];47(1):147-57. Disponível em: Disponível em: https://doi.org/10.1590/S0034-89102013000100019
https://doi.org/10.1590/S0034-8910201300... that result is different to the one found in Tocantins, where these percentages were high. This finding is of concern for the state, since delay in starting prenatal care is associated with greater risk of occurrence of CS.¹²12. Rodrigues CS, Guimarães MDC. Grupo Nacional de Estudo sobre Sífilis Congênita. Positividade para sífilis em puérperas: ainda um desafio para o Brasil. Rev Panam Salud Pública [Internet]. 2004 set [citado 2020 mar 2];16(3):168-75. Disponível em: Disponível em: https://pdfs.semanticscholar.org/6723/98d3a5171cd7615bcb02eb584cba16cad58a.pdf
https://pdfs.semanticscholar.org/6723/98...

13. Campos AL, Araújo MAL, Melo SP, Gonçalves MLC. Epidemiologia da sífilis gestacional em Fortaleza, Ceará, Brasil: um agravo sem controle. Cad Saúde Pública [Internet]. 2010 set [citado 2020 mar 2];26(9):1747-55. Disponível em: Disponível em: https://doi.org/10.1590/S0102-311X2010000900008
https://doi.org/10.1590/S0102-311X201000... ^-1414. Domingues RMSM, Leal MC. Incidência de sífilis congênita e fatores associados à transmissão vertical da sífilis: dados do estudo ‘Nascer no Brasil’. Cad Saúde Pública [Internet]. 2016 jun [citado 2020 mar 2];32(6):e00082415. Disponível em: Disponível em: https://doi.org/10.1590/0102-311X00082415
https://doi.org/10.1590/0102-311X0008241...

Considering that starting prenatal follow-up in the first trimester of pregnancy is an indicator of the quality of maternal health care,⁹9. Organização Pan-Americana da Saúde. Plano estratégico regional para HIV/AIDS e IST 2006-2015: avaliação intermediária [Internet]. CSP28/INF/3 (Port.). S.l.: Organização Pan-Americana da Saúde; 2005 [citado 2012 out 16]. p. 20-26. Disponível em: Disponível em: https://iris.paho.org/bitstream/handle/10665.2/34233/CSP28-INF-3-D-p.pdf?sequence=19&isAllowed=y
https://iris.paho.org/bitstream/handle/1... ^,55. Ministério da Saúde (BR). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Atenção ao pré-natal de baixo risco. Brasília: Ministério da Saúde ; 2012 [citado 2020 mar 2]. 318 p. (Cadernos de Atenção Básica n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... the hypothesis can be raised that in Tocantins such care is still insufficient. In this study, the majority of mothers diagnosed with syphilis were not submitted to treatment or treatment was inadequate. The same situation was found in Belo Horizonte.¹⁵15. Lafetá KRG, Martelli Júnior H, Silveira MF, Paranaíba LMR. Sífilis materna e congênita, subnotificação e difícil controle. Rev Bras Epidemiol [Internet]. 2016 jan-mar [citado 2020 mar 2];19(1):63-74. Disponível em: Disponível em: https://doi.org/10.1590/1980-5497201600010006
https://doi.org/10.1590/1980-54972016000... This is made worse by the fact that 83.0% of the partners of these pregnant women were not treated for syphilis.

Standing out in Tocantins is the low proportion of live births with CS who underwent the cerebrospinal fluid examination including VDRL, this test being fundamental for decision making on the intravenous use of crystalline penicillin instead of procaine penicillin. The latter is not an option in the event of the possibility of the newborn baby having neurosyphilis.¹⁶16. Costa CC, Freitas LV, Sousa DMN, Oliveira LL, Chagas ACMA, Lopes MVO, et al. Sífilis congênita no Ceará: análise epidemiológica de uma década. Rev Esc Enferm USP [Internet]. 2013 fev [citado 2020 mar 2];47(1):152-9. Disponível em: Disponível em: https://doi.org/10.1590/S0080-62342013000100019
https://doi.org/10.1590/S0080-6234201300... ^,1717. Guinsburg R, Santos AMN. Critérios diagnósticos e tratamento da sífilis congênita [Internet]. Documento científico - Departamento de Neonatologia. São Paulo: Sociedade Brasileira de Pediatria; 2010 [citado 2020 mar 2]. Disponível em: Disponível em: https://www.sbp.com.br/fileadmin/user_upload/2015/02/tratamento_sifilis.pdf
https://www.sbp.com.br/fileadmin/user_up...

One of the explanations for the CS spatial distribution pattern found in this study, according to which CS incidence was concentrated in just 8.6% of the state’s municipalities, may be the fact that they are the most populous municipalities and are more likely to have a health service network that is better structured and trained for performing diagnosis. Consideration must also be given to a possible weakness in the information systems of the remaining municipalities and the complexity involved in diagnosing CS in the newborn, given that the majority of babies infected with Treponema pallidum may be asymptomatic at birth, with VDRL titers lower than maternal titers, in addition to the difficulty in performing the cerebrospinal fluid examination.

As this study was conducted using secondary data and was concerned with a disease that is hard to diagnose in the newborn, its results need to be interpreted with caution in view of case underreporting. Nevertheless, this limitation points to the possibility of the epidemiological situation in Tocantins being even more serious than that shown in the profile described here. Moreover, data aggregated over a long period may not necessarily reflect the current distribution pattern of the disease.

Initial conduct for congenital syphilis detection and treatment is not completely in agreement with Ministry of Health guidelines:³3. Ministério da Saúde (BR). Secretaria de Vigilância em Saúde. Sífilis 2017. Bol Epidemiol [Internet]. 2017 [citado 2018 dez 10];48(36). Disponível em: http://www.aids.gov.br/pt-br/pub/2017/boletim-epidemiologico-de-sifilis-2017 the majority of cases have been diagnosed late and this may cause adverse consequences for affected children. From this perspective, it is important to highlight the importance of intensifying syphilis surveillance, prevention and control actions, including improved prenatal care.

References

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