Etiological Surveillance of Genital Ulcer Syndrome in South Africa: 2019 to 2020

Abstract

Herpes simplex virus 2 is the predominant cause of genital ulcer syndrome in South Africa; however, the relative prevalence of syphilis is considerable and seems to be increasing.

Dramatic Shift in the Etiology of Genital Ulcer Disease Among Patients Visiting a Sexually Transmitted Infections Clinic in Lilongwe, Malawi

“…Compared with historical estimates, the increase we observed in syphilis prevalence was substantial: in the early 2000s in the Malawian STI clinical care setting, only 6% of all ulcers had detectable T. pallidum and more than 5% of ulcers from patients without HIV compared with the nearly two-thirds (60%) recovered from ulcers in the present study 7 . In South Africa, the prevalence of syphilis-positive ulcerative disease has also increased, from a historically stable average of 10% to current estimates of ~26%, and a recent report from Zimbabwe suggests a similar potential reemergence of syphilis 3,15 . Malawi had observed a steady decline in syphilis seropositivity prevalence according to national surveillance programs—declining from 7% in the late 1990s to around 1% in 2007 20 .…”

“…Nonsyphilis and non–HSV-related etiologies persisted relatively unchanged. The prevalence of H. ducreyi was remarkably stable compared with historical estimates (15%) but significantly higher than other areas in sub-Saharan Africa including South Africa, Zambia, and Zimbabwe, where no cases of H. ducreyi were identified among assessments with >100 participants 3,15,24 . The persistence of this disease in Malawi despite presumed widespread access to syndromic management warrants further investigation into transmission dynamics and treatment.…”

“…Although C. trachomatis (i.e., potential LGV) was the least common etiology, with estimates consistent with past reports from Malawi, 7 our estimates are higher than assessments from South Africa (1%) and Zimbabwe (1%). However, both of these studies reported LGV-specific serovars 3,15 ; because we did not distinguish between C. trachomatis serovars and no urogenital testing was done, we are unable to confirm LGV diagnosis and exclude any contamination from urogenital C. trachomatis infections, likely overestimating the prevalence of LGV. Our prevalence estimate (6%) likely represents a mix of LGV and urogenital C. trachomatis and is similar to an assessment in Zambia (4%), which also did not distinguish between serovars 24 .…”

“…We identified an etiology in more than 90% of participants. In contrast, historically 20% to 30% of ulcers subjected to the same PCR tests in Malawi or South Africa have not had an identifiable etiology confirmed 7,15 . This reduction may be related to the shifting etiology of GUD in the region in the context of declining HIV prevalence.…”

A Sore Subject? An Examination of National Case–Based Chancroid Surveillance

“…Critical review of the system's attributes based on available evidence and key informant interviews suggest that national case-based chancroid surveillance data have limited ability to monitor national trends. Although the overall decline in reported chancroid cases in the United States likely reflects a decline in disease incidence (as observed in previous endemic countries), 20,21 these data should be interpreted with caution because H. ducreyi is difficult to definitively diagnose: clinical diagnoses may be unreliable due to limitations in diagnostic testing or because tests are not performed 10 and the current surveillance case definition likely misses most H. ducreyi infections because the laboratory methodology required to confirm cases (culture) is not readily available.…”