Temporal Trend of Gestational Syphilis between 2008 and 2018 in Brazil: Association with Socioeconomic and Health Care Factors

Abstract

The increased number of cases in recent years has turned syphilis into a global public health problem. In 2020, 115,371 cases of acquired syphilis were reported (detection rate of 54.5 cases/100,000 inhabitants) in Brazil. In that same period, the country notified 61,441 cases of gestational syphilis (detection rate of 21.6 per 1000 live births). The number of syphilis cases points to the need to reinforce surveillance, prevention, and infection control actions, which is a worrying scenario for government organizations. This study aims to describe the temporal trend of gestational syphilis from 2008 to 2018 in Brazilian regions and to associate its detection rate with socioeconomic and health care indicators. We conducted an ecological study of temporal trends using secondary data from the Department of Informatics of the Unified Health System. The temporal trend was analyzed using the Joinpoint Regression program. The annual percent change (APC) and 95% confidence intervals (95%CI) were estimated and tested; statistical significance was assessed using the Monte Carlo permutation test. Correlations were assessed using Pearson's correlation coefficient, and statistical significance was calculated using Pearson's product-moment correlation. The gestational syphilis detection rate increased between 2008 and 2018. The South region showed the greatest trend, whereas the Midwest region presented the lowest trend. The following variables were significantly correlated with the gestational syphilis detection rate: Municipal Human Development Index, illiteracy rate, percentage of primary health care coverage, and proportion of doctors, nurses, and basic health units per inhabitant. Health policies are needed to mitigate social vulnerabilities and strengthen primary health care.

Keywords: Treponema pallidum; communicable diseases; pregnancy; prenatal care; syphilis.

Figure 1

Time series of gestational syphilis detection rate in Brail and all Brazilian regions, according to the Joinpoint model. Brazil, 2008 to 2018. Indicates that the annual percent change is significant.

Figure 2

Time series of gestational syphilis detection rate in Brazil (A) and by region (South (B), Southeast (C), North (D), Northeast (E), and Midwest (F)), according to the Joinpoints model. Brazil, 2008 to 2018. ^ Indicates that the annual percent change is significant.