—from Epidemiological
Bulletin, Vol. 21 No. 4, December 2000—
Case Definition:
Syphilis
Rationale for surveillance
Although cases of syphilis decreased dramatically after the introduction of
penicillin treatment in 1946, syphilis reemerged in the end of the sixties and
has remained at high incidence levels in developing countries. Developed countries
are now also experiencing outbreaks and countries in economic transition are
experiencing a marked and widespread recrudescence. Syphilis prevalence data
in pregnant women provide information about both latent and symptomatic syphilis
in this group, and minimize the problems associated with general reporting of
sexually transmitted syndromes (STD), which are subject to variations in health
care seeking behavior. Thus, it can be considered an approximation of syphilis
prevalence in the general population. This information should be used for policy
formulation, planning and evaluation of STD control.
Recommended case definition
Clinical description: the signs and symptoms of syphilis are multiple.
The primary stage usually, but not necessarily, involves ulceration of the external
genital organs and local lymphadenopathy; secondary and tertiary syphilis show
mainly dermatological and systemic manifestations. For surveillance purposes,
only confirmed cases (see below) will be considered.
Confirmed case: a person with a confirmed positive serology for syphilis
(Rapid Plasma Reagin (RPR) or VDRL confirmed by TPHA (Treponema pallidum haemagglutination
antibodies) or FTA (fluorescent treponemal antibody-absorption).
Case classification
Congenital syphilis: an infant with a positive serology, whether or not the
mother had a positive serology during the pregnancy.
Acquired syphilis: all others.
Recommended types of surveillance
· Laboratory-based surveillance through screening of pregnant women
· Routine reporting from antenatal (AN) clinics and sentinel sites of AN clinics
· Active case finding from prevalence surveys in pregnancy
Only confirmed cases should be reported to intermediate and central level
by:
· Routine case-based or aggregate reporting
· Periodic surveillance reports
Recommended minimum data elements
Aggregated data
Number of cases of positive serology for syphilis by age group, month, geographical
area. Number of cases of congenital syphilis by age group, years, geographical
area.
Performance indicators
False-positive rate at sentinel sites according to type of test (TPHA / FT-AB).
Recommended data analyses, presentations, reports
· Cases / incidence by geographical area, age, parity .
· Comparisons with age group and geographical area in previous years (line graph).
· Rate of congenital syphilis by geographical area by year (line graph).
· Annual surveillance summaries to be produced nationally and regionally and
feed back to original data sources..
Principal uses of data for decision-making
· Document syphilis prevalence by screening pregnant women as a surrogate for
general population
· Monitor trends in disease incidence
· Advocate syphilis control, and interventions
· Identify high risk areas for further targeting intervention
· Identify areas and populations where HIV prevention activities should be enhanced
Return to the Index,
Epidemiological Bulletin , Vol.
21 No. 4, December 2000
