Trends and characteristics of congenital syphilis in children under 1 year of age: a time series analysis, municipality of Rio de Janeiro, 2007-2021.

OBJECTIVE

To analyze the trend and characteristics of reported cases of congenital syphilis in children under 1 year of age in the municipality of Rio de Janeiro, from 2007 to 2021.

METHODS

: This study employed a time series analysis using aggregated data from the Notifiable Health Conditions Information System and the Live Birth Information System. The trend in congenital syphilis rates was estimated using joinpoint regression analysis. The annual percentage change (APC) and its respective statistical significance (p-value≤0.05) were calculated for each identified segment.

RESULTS

A total of 18,544 cases of congenital syphilis were reported during the study period. The congenital syphilis rate increased from 2007 to 2012 (APC 22.2; p-value<0.001), followed by a decline until 2019 (APC -13.7; p-value 0.137), and a subsequent resurgence (APC 17.1; p-value 0.269). Black mothers had proportionally lower levels of education (12.5%), were more frequently adolescents (26.6%), had lower rates of prenatal care (86.7%), and lower rates of syphilis treatment during pregnancy (31.8%) and partner treatment (80.1%) compared to White mothers (p-value ≤0.013).

CONCLUSION

The incidence rate of congenital syphilis in children under 1 year of age showed a marked increase until 2012, followed by a decline and a resurgence in 2020. The rate varied across planning areas and was higher among children born to Black mothers and residents of slums, although diagnosis and treatment are effective and low-cost.