Trends of syphilis in Brazil: a growth portrait of the treponemic epidemic

Syphilis is a
chronic infectious disease with its prevalence being described since the 15th
century. Although its etiological agent and also the treatment measures are
widely known, syphilis is still a great public health problem worldwide, mainly
in countries with limited resources associated to low investments in health
primary care. The aim of the present study was to analyze the trend and regional distribution of
syphilis in Brazil between 2007 and 2017. This is an ecological study using
secondary data from the Brazilian notification system. The Ministry of Health selected
100 municipalities which presented the worse outcomes related to syphilis from
the 5,570 Brazilian municipalities as a target for a comprehensive project in
order to tackle the prevalence of syphilis, called the “No Syphilis Project”.
These priority municipalities represent 57.7% of syphilis cases and about one
third of the Brazilian population. They were compared with other 189 non-priority
municipalities with more than 100 thousand inhabitants among the Brazilian
regions (North, Northeast, Southeast, South and Center-West). Polynomial
regression methods and Joinpoint analyses were used to analyze the trend, from
which the Annual Average Percent Change (AACP) for each time period was
calculated. There was a significant growth trend in all regions for the main
three forms of syphilis (in pregnancy, congenital and acquired), especially in
the South. The ratio between syphilis in pregnancy and congenital syphilis increased
in both priority (AAPC: 8.54%; p<0.001)
and non-priority municipalities (AAPC: 2.61%; p=0.005), as well as in the regions, except the Center-West. High
growth trends in syphilis prevalence were found in all municipalities, as well
as all five regions between 2007 and 2017, showing that the challenge to reduce
or even eliminate syphilis in Brazil is still difficult.