Neurosyphilis Increases Human Immunodeficiency Virus (HIV)-associated Central Nervous System Inflammation but Does Not Explain Cognitive Impairment in HIV-infected Individuals With Syphilis.

Background: Individuals infected with human immunodeficiency virus (HIV) who have previously had syphilis may have cognitive impairment. We tested the hypothesis that neurosyphilis causes cognitive impairment in HIV by amplifying HIV-related central nervous system (CNS) inflammation. Methods: HIV-infected participants enrolled in a study of cerebrospinal fluid (CSF) abnormalities in syphilis underwent the mental alternation test (MAT), venipuncture, and lumbar puncture. CSF concentrations of chemokine (C-X-C motif) ligand 10 (CXCL10), chemokine (C-C motif) ligand 2 (CCL2), and neurofilament light (NFL) were determined by commercial assays. The proportion of peripheral blood mononuclear cells (PBMCs) and of CSF white blood cells (WBCs) that were activated monocytes (CD14+CD16+) was determined by flow cytometry. Neurosyphilis was defined as detection of Treponema pallidum 16S RNA in CSF or CSF white blood cells (WBCs) \u3e20/uL or a reactive CSF-Venereal Disease Research Laboratory (VDRL) test; uncomplicated syphilis was defined as undetectable CSF T. pallidum, CSF WBCs ≤5/uL and nonreactive CSF-VDRL. MATlow. Results: Median proportion of PBMCs that were activated monocytes (16.6 vs. 5.3), and median CSF CXCL10 (10658 vs. 2530 units), CCL2 (519 vs. 337 units) and HIV RNA (727 vs. 50 c/mL) were higher in neurosyphilis than in uncomplicated syphilis (P ≤ .001 for all comparisons). Neurosyphilis was not related to low MAT scores. Participants with low MAT scores had higher median CSF CXCL10 (10299 vs. 3650 units, P = .008) and CCL2 (519 vs. 365 units, P = .04) concentrations than those with high MAT scores. Conclusions: Neurosyphilis may augment HIV-associated CNS inflammation, but it does not explain cognitive impairment in HIV-infected individuals with syphilis

Diagnostics for Yaws Eradication: Insights From Direct Next-Generation Sequencing of Cutaneous Strains of Treponema pallidum.

Background: Yaws-like chronic ulcers can be caused by Treponema pallidum subspecies pertenue, Haemophilus ducreyi, or other, still-undefined bacteria. To permit accurate evaluation of yaws elimination efforts, programmatic use of molecular diagnostics is required. The accuracy and sensitivity of current tools remain unclear because our understanding of T. pallidum diversity is limited by the low number of sequenced genomes. Methods: We tested samples from patients with suspected yaws collected in the Solomon Islands and Ghana. All samples were from patients whose lesions had previously tested negative using the Centers for Disease Control and Prevention (CDC) diagnostic assay in widespread use. However, some of these patients had positive serological assays for yaws on blood. We used direct whole-genome sequencing to identify T. pallidum subsp pertenue strains missed by the current assay. Results: From 45 Solomon Islands and 27 Ghanaian samples, 11 were positive for T. pallidum DNA using the species-wide quantitative polymerase chain reaction (PCR) assay, from which we obtained 6 previously undetected T. pallidum subsp pertenue whole-genome sequences. These show that Solomon Islands sequences represent distinct T. pallidum subsp pertenue clades. These isolates were invisible to the CDC diagnostic PCR assay, due to sequence variation in the primer binding site. Conclusions: Our data double the number of published T. pallidum subsp pertenue genomes. We show that Solomon Islands strains are undetectable by the PCR used in many studies and by health ministries. This assay is therefore not adequate for the eradication program. Next-generation genome sequence data are essential for these efforts

Transcription of TP0126, Treponema pallidum Putative OmpW Homolog, Is Regulated by the Length of a Homopolymeric Guanosine Repeat

An effective mechanism for introduction of phenotypic diversity within a bacterial population exploits changes in the length of repetitive DNA elements located within gene promoters. This phenomenon, known as phase variation, causes rapid activation or silencing of gene expression and fosters bacterial adaptation to new or changing environments. Phase variation often occurs in surface-exposed proteins, and in Treponema pallidum subsp. pallidum, the syphilis agent, it was reported to affect transcription of three putative outer membrane protein (OMP)-encoding genes. When the T. pallidum subsp. pallidum Nichols strain genome was initially annotated, the TP0126 open reading frame was predicted to include a poly(G) tract and did not appear to have a predicted signal sequence that might suggest the possibility of its being an OMP. Here we show that the initial annotation was incorrect, that this poly(G) is instead located within the TP0126 promoter, and that it varies in length in vivo during experimental syphilis. Additionally, we show that TP0126 transcription is affected by changes in the poly(G) length consistent with regulation by phase variation. In silico analysis of the TP0126 open reading frame based on the experimentally identified transcriptional start site shortens this hypothetical protein by 69 amino acids, reveals a predicted cleavable signal peptide, and suggests structural homology with the OmpW family of porins. Circular dichroism of recombinant TP0126 supports structural homology to OmpW. Together with the evidence that TP0126 is fully conserved among T. pallidum subspecies and strains, these data suggest an important role for TP0126 in T. pallidum biology and syphilis pathogenesis

Haemophilus ducreyi as a cause of skin ulcers in children from a yaws-endemic area of Papua New Guinea: a prospective cohort study

Background Skin infections with ulceration are a major health problem in countries of the south Pacifi c region. Yaws, caused by Treponema pallidum subspecies pertenue and diagnosed by the presence of skin ulcers and a reactive syphilis serology, is one major cause, but this infection can be confused clinically with ulcers due to other causative agents. We investigated T pallidum pertenue and another bacterium known to cause skin infections in the Pacifi c islands— Haemophilus ducreyi—as causes of skin ulceration in a yaws-endemic region. Additionally, we identifi ed specifi c signs and symptoms associated with these causative agents of cutaneous ulcers and compared these fi ndings with laboratory-based diagnoses. Methods We did a prospective cohort study of fi ve yaws-endemic villages (total population 3117 people) during a yaws elimination campaign in Papua New Guinea in April, 2013. We enrolled all consenting patients with chronic moist or exudative skin ulcers. We undertook a detailed dermatological assessment, syphilis serology, and PCR on lesional swabs to detect the presence of T pallidum pertenue and H ducreyi. Patients with PCR-confi rmed bacterial infections were included in a comparative analysis of demographics and clinical features. Findings Full outcome data were available for 90 people with skin ulcers. Of these patients, 17 (19%) had negative results in all molecular tests and were therefore excluded from the comparative analyses. A bacterial cause was identifi ed in 73 (81%) participants—either H ducreyi (n=42), T pallidum pertenue (yaws; n=19), or coinfection with both organisms (dual infection; n=12). The demographic characteristics of the patients infected with yaws and with H ducreyi were similar. Skin lesions in patients with yaws and in those with dual infection were larger than those in patients infected with H ducreyi (p=0·071). The lesions in patients with yaws and dual infection were more circular in shape (79% and 67%) than in those infected with H ducreyi (21%; p<0·0001); more likely to have central granulating tissue (90% and 67% vs 14%; p<0·0001); and more likely to have indurated edges (74% and 83% vs 31%; p=0·0003). The prevalence of reactive combined serology (positive T pallidum haemagglutination test and rapid plasmin reagin titre of ≥1:8) was higher in cases of yaws (63%) and dual infections (92%) than in H ducreyi infections (29%; p<0·0001). Interpretation In this yaws-endemic community, H ducreyi is an important and previously unrecognised cause of chronic skin ulceration. Reactive syphilis serology caused by latent yaws can occur in ulcers with the presence of H ducreyi alone. The introduction of PCR for ulcer surveillance could improve the accuracy of diagnosis in countries with yaws eradication campaigns

Re-emergence of yaws after single mass azithromycin treatment followed by targeted treatment: a longitudinal study

Background: Yaws is a substantial cause of chronic disfiguring ulcers in children in at least 14 countries in the tropics. WHO's newly adopted strategy for yaws eradication uses a single round of mass azithromycin treatment followed by targeted treatment programmes, and data from pilot studies have shown a short-term significant reduction of yaws. We assessed the long-term efficacy of the WHO strategy for yaws eradication. Methods: Between April 15, 2013, and Oct 24, 2016, we did a longitudinal study on a Papua New Guinea island (Lihir; 16 092 population) in which yaws was endemic. In the initial study, the participants were followed for 12 months; in this extended follow-up study, clinical, serological, and PCR surveys were continued every 6 months for 42 months. We used genotyping and travel history to identify importation events. Active yaws confirmed by PCR specific for Treponema pallidum was the primary outcome indicator. The study is registered with ClinicalTrials.gov, number NCT01955252. Findings: Mass azithromycin treatment (coverage rate of 84%) followed by targeted treatment programmes reduced the prevalence of active yaws from 1·8% to a minimum of 0·1% at 18 months (difference from baseline −1·7%, 95% CI, −1·9 to −1·4; p<0·0001), but the infection began to re-emerge after 24 months with a significant increase to 0·4% at 42 months (difference from 18 months 0·3%, 95% CI 0·1 to 0·4; p<0·0001). At each timepoint after baseline, more than 70% of the total community burden of yaws was found in individuals who had not had the mass treatment or as new infections in non-travelling residents. At months 36 and 42, five cases of active yaws, all from the same village, showed clinical failure following azithromycin treatment, with PCR-detected mutations in the 23S ribosomal RNA genes conferring resistance to azithromycin. A sustained decrease in the prevalence of high-titre latent yaws from 13·7% to <1·5% in asymptomatic children aged 1–5 years old and of genetic diversity of yaws strains from 0·139 to less than 0·046 between months 24 and 42 indicated a reduction in transmission of infection. Interpretation: The implementation of the WHO strategy did not, in the long-term, achieve elimination in a high-endemic community mainly due to the individuals who were absent at the time of mass treatment in whom yaws reactivated; repeated mass treatment might be necessary to eliminate yaws. To our knowledge, this is the first report of the emergence of azithromycin-resistant T p pertenue and spread within one village. Communities' surveillance should be strengthened to detect any possible treatment failure and biological markers of resistance

Effectiveness of single-dose azithromycin to treat latent yaws: a longitudinal comparative cohort study

BACKGROUND: Treatment of latent yaws is a crucial component of the WHO yaws eradication strategy to prevent relapse and the resulting transmission to uninfected children. We assessed the effectiveness of single-dose azithromycin to treat patients with latent yaws. METHODS: This population-based cohort study included children (age <20 years) living on Lihir Island, Papua New Guinea, with high-titre (rapid plasma reagin titre >/=1:8) latent or active yaws, between April, 2013, and May, 2015. Latent yaws was defined as lack of suspicious skin lesions or presence of ulcers negative for Treponema pallidum subsp pertenue on PCR, and active yaws was defined as ulcers positive for T pertenue on PCR. All children received one oral dose of 30 mg/kg azithromycin. The primary endpoint was serological cure, defined as a two-dilution decrease in rapid plasma reagin titre by 24 months after treatment. Treatment of latent yaws was taken to be non-inferior to that of active yaws if the lower limit of the two-sided 95% CI for the difference in rates was higher than or equal to -10%. This study is registered with ClinicalTrials.gov, number NCT01955252. FINDINGS: Of 311 participants enrolled, 273 (88%; 165 with latent yaws and 108 with active yaws) completed follow-up. The primary endpoint was achieved in 151 (92%) participants with latent yaws and 101 (94%) with active yaws (risk difference -2.0%, 95% CI -8.3 to 4.3), meeting the prespecified criteria for non-inferiority. INTERPRETATION: On the basis of decline in serological titre, oral single-dose azithromycin was effective in participants with latent yaws. This finding supports the WHO strategy for the eradication of yaws based on mass administration of the entire endemic community irrespective of clinical status. FUNDING: Newcrest Mining Limited and ISDIN laboratories

Survey of Treponemal Infections in Free-Ranging and Captive Macaques, 1999-2012.

Survey results showed treponemal infection among pet macaques in Southeast Asia, a region with a high prevalence of human yaws. This finding, along with studies showing treponemal infection in nonhuman primates in Africa, should encourage a One Health approach to yaws eradication and surveillance activities, possibly including monitoring of nonhuman primates in yaws-endemic regions