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1.
PLoS One ; 15(3): e0230288, 2020.
Article de Anglais | MEDLINE | ID: mdl-32160272

RÉSUMÉ

BACKGROUND: Treponema pallidum subspecies pallidum (TPA) and subsp. endemicum (TEN) are the causative agents of syphilis and bejel, respectively. TEN shows similar clinical manifestations and is morphologically and serologically indistinguishable from TPA. Recently, bejel was found outside of its assumed endemic areas. Using molecular typing we aimed to discover bejel and characterize circulating TPA types among syphilis cases with Surinamese, Antillean and Dutch ethnicity in Amsterdam. METHODS: DNA was extracted from 137 ulcer swabs, which tested positive in the in-house diagnostic PCR targeting the polA gene. Samples were collected between 2006 and 2018 from Surinamese, Antillean and Dutch patients attending the Amsterdam STI clinic. Multilocus sequence typing was performed by partial sequence analysis of the tp0136, tp0548 and tp0705 genes. In addition, the 23S rRNA loci were analyzed for A2058G and A2059G macrolide resistance mutations. RESULTS: We found 17 distinct allelic profiles in 103/137 (75%) fully typed samples, which were all TPA and none TEN. Of the strains, 82.5% were SS14-like and 17.5% Nichols-like. The prevalence of Nichols-like strains found in this study is relatively high compared to nearby countries. The most prevalent types were 1.3.1 (42%) and 1.1.1 (19%), in concordance with similar TPA typing studies. The majority of the TPA types found were unique per country. New allelic types (7) and profiles (10) were found. The successfully sequenced 23S rRNA loci from 123/137 (90%) samples showed the presence of 79% A2058G and 2% A2059G mutations. CONCLUSIONS: No TEN was found in the samples from different ethnicities residing in Amsterdam, the Netherlands, so no misdiagnoses occurred. Bejel has thus not (yet) spread as a sexually transmitted disease in the Netherlands. The strain diversity found in this study reflects the local male STI clinic population which is a diverse, mixed group.


Sujet(s)
Gènes bactériens , Syphilis/microbiologie , Treponema pallidum/génétique , Adulte , Allèles , Codage à barres de l'ADN pour la taxonomie , Ethnies/statistiques et données numériques , Humains , Pays-Bas , Antilles néerlandaises , Suriname , Syphilis/épidémiologie , Syphilis/ethnologie , Treponema pallidum/classification , Treponema pallidum/pathogénicité
2.
PLoS Negl Trop Dis ; 11(9): e0005894, 2017 Sep.
Article de Anglais | MEDLINE | ID: mdl-28886021

RÉSUMÉ

BACKGROUND: Treponema pallidum subsp. pertenue (TPE) is the causative agent of yaws, a multi-stage disease, endemic in tropical regions of Africa, Asia, Oceania, and South America. To date, four TPE strains have been completely sequenced including three TPE strains of human origin (Samoa D, CDC-2, and Gauthier) and one TPE strain (Fribourg-Blanc) isolated from a baboon. All TPE strains are highly similar to T. pallidum subsp. pallidum (TPA) strains. The mutation rate in syphilis and related treponemes has not been experimentally determined yet. METHODOLOGY/PRINCIPAL FINDINGS: Complete genomes of two TPE strains, CDC 2575 and Ghana-051, that infected patients in Ghana and were isolated in 1980 and 1988, respectively, were sequenced and analyzed. Both strains had identical consensus genome nucleotide sequences raising the question whether TPE CDC 2575 and Ghana-051 represent two different strains. Several lines of evidence support the fact that both strains represent independent samples including regions showing intrastrain heterogeneity (13 and 5 intrastrain heterogeneous sites in TPE Ghana-051 and TPE CDC 2575, respectively). Four of these heterogeneous sites were found in both genomes but the frequency of alternative alleles differed. The identical consensus genome sequences were used to estimate the upper limit of the yaws treponeme evolution rate, which was 4.1 x 10-10 nucleotide changes per site per generation. CONCLUSIONS/SIGNIFICANCE: The estimated upper limit for the mutation rate of TPE was slightly lower than the mutation rate of E. coli, which was determined during a long-term experiment. Given the known diversity between TPA and TPE genomes and the assumption that both TPA and TPE have a similar mutation rate, the most recent common ancestor of syphilis and yaws treponemes appears to be more than ten thousand years old and likely even older.


Sujet(s)
Génome bactérien , Treponema pallidum/génétique , Treponema pallidum/isolement et purification , Pian/microbiologie , Animaux , Asie/épidémiologie , Cartographie chromosomique , Escherichia coli/génétique , Ghana/épidémiologie , Humains , Mutation , Papio/microbiologie , Analyse de séquence d'ADN , Amérique du Sud/épidémiologie , Facteurs temps , Treponema pallidum/classification , Pian/épidémiologie
3.
Sex Transm Infect ; 91(6): 415-22, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-25688105

RÉSUMÉ

INTRODUCTION: Previous studies found conflicting results regarding associations between urogenital Chlamydia trachomatis infections and ethnicity or urogenital symptoms among at-risk populations using either ompA-based genotyping or high-resolution multilocus sequence typing (MLST). This study applied high-resolution MLST on samples of individuals from a selected young urban screening population to assess the relationship of C. trachomatis strain types with ethnicity and self-reported urogenital symptoms. Demographic and sexual risk behaviour characteristics of the identified clusters were also analysed. METHODS: We selected C. trachomatis-positive samples from the Dutch Chlamydia Screening Implementation study among young individuals in Amsterdam, the Netherlands. All samples were typed using high-resolution MLST. Clusters were assigned using minimum spanning tree analysis and were combined with epidemiological data of the participants. RESULTS: We obtained full MLST data for C. trachomatis-positive samples from 439 participants and detected nine ompA genovars. MLST analysis identified 175 sequence types and six large clusters; in one cluster, participants with Surinamese/Antillean ethnicity were over-represented (58.8%) and this cluster predominantly consisted of genovar I. In addition, we found one cluster with an over-representation of participants with Dutch ethnicity (90.0%) and which solely consisted of genovar G. No association was observed between C. trachomatis clusters and urogenital symptoms. CONCLUSIONS: We found an association between urogenital C. trachomatis clusters and ethnicity among young screening participants in Amsterdam, the Netherlands. However, no association was found between C. trachomatis clusters and self-reported urogenital symptoms.


Sujet(s)
Infections à Chlamydia/génétique , Chlamydia trachomatis/génétique , Traçage des contacts/méthodes , Émigrants et immigrants/statistiques et données numériques , Typage par séquençage multilocus , Comportement sexuel/statistiques et données numériques , Adolescent , Adulte , Infections à Chlamydia/diagnostic , Infections à Chlamydia/épidémiologie , Chlamydia trachomatis/isolement et purification , Analyse de regroupements , Ethnies , Femelle , Génotype , Humains , Mâle , Pays-Bas/épidémiologie , Réaction de polymérisation en chaîne , Prévalence , Analyse de séquence d'ADN , Suriname/épidémiologie , Rapports sexuels non protégés , Population urbaine
4.
PLoS One ; 8(11): e77977, 2013.
Article de Anglais | MEDLINE | ID: mdl-24236009

RÉSUMÉ

The large Surinamese migrant population in the Netherlands is a major risk group for urogenital Chlamydia trachomatis infection. Suriname, a former Dutch colony, also has a high prevalence of C. trachomatis. Surinamese migrants travel extensively between the Netherlands and Suriname. Our objective was to assess whether the Surinamese migrants in the Netherlands form a bridge population facilitating transmission of C. trachomatis between Suriname and the Netherlands. If so, joint prevention campaigns involving both countries might be required. Between March 2008 and July 2010, participants were recruited at clinics in Paramaribo, Suriname and in Amsterdam, the Netherlands. Participants were grouped as native Surinamese, native Dutch, Surinamese migrant, Dutch migrant, or Other, based on country of residence and country of birth of the participant and of their parents. Risk behavior, such as sexual mixing between ethnic groups, was recorded and C. trachomatis positive samples were typed through multilocus sequence typing (MLST). A minimum spanning tree of samples from 426 participants showed four MLST clusters. The MLST strain distribution of Surinamese migrants differed significantly from both the native Surinamese and Dutch populations, but was not an intermediate state between these two populations. Sexual mixing between the Surinamese migrants and the Dutch and Surinamese natives occurred frequently. Yet, the MLST cluster distribution did not differ significantly between participants who mixed and those who did not. Sexual mixing occurred between Surinamese migrants in Amsterdam and the native populations of Suriname and the Netherlands. These migrants, however, did not seem to form an effective bridge population for C. trachomatis transmission between the native populations. Although our data do not seem to justify the need for joint campaigns to reduce the transmission of C. trachomatis strains between both countries, intensified preventive campaigns to decrease the C. trachomatis burden are required, both in Suriname and in the Netherlands.


Sujet(s)
Infections à Chlamydia/transmission , Chlamydia trachomatis/génétique , Adulte , Infections à Chlamydia/épidémiologie , Infections à Chlamydia/microbiologie , Analyse de regroupements , Traçage des contacts , Émigrants et immigrants , Femelle , Humains , Mâle , Typage par séquençage multilocus , Pays-Bas/épidémiologie , Prévalence , Prise de risque , Suriname/épidémiologie , Suriname/ethnologie , Rapports sexuels non protégés , Jeune adulte
5.
PLoS One ; 8(7): e68698, 2013.
Article de Anglais | MEDLINE | ID: mdl-23874730

RÉSUMÉ

BACKGROUND: Little is known about the epidemiology of urogenital Chlamydia trachomatis infection (chlamydia) in Suriname. Suriname is a society composed of many ethnic groups, such as Creoles, Maroons, Hindustani, Javanese, Chinese, Caucasians, and indigenous Amerindians. We estimated determinants for chlamydia, including the role of ethnicity, and identified transmission patterns and ethnic sexual networks among clients of two clinics in Paramaribo, Suriname. METHODS: Participants were recruited at two sites a sexually transmitted infections (STI) clinic and a family planning (FP) clinic in Paramaribo. Urine samples from men and nurse-collected vaginal swabs were obtained for nucleic acid amplification testing. Logistic regression analysis was used to identify determinants of chlamydia. Multilocus sequence typing (MLST) was performed to genotype C. trachomatis. To identify transmission patterns and sexual networks, a minimum spanning tree was created, using full MLST profiles. Clusters in the minimum spanning tree were compared for ethnic composition. RESULTS: Between March 2008 and July 2010, 415 men and 274 women were included at the STI clinic and 819 women at the FP clinic. Overall chlamydia prevalence was 15% (224/1508). Age, ethnicity, and recruitment site were significantly associated with chlamydia in multivariable analysis. Participants of Creole and Javanese ethnicity were more frequently infected with urogenital chlamydia. Although sexual mixing with other ethnic groups did differ significantly per ethnicity, this mixing was not independently significantly associated with chlamydia. We typed 170 C. trachomatis-positive samples (76%) and identified three large C. trachomatis clusters. Although the proportion from various ethnic groups differed significantly between the clusters (P = 0.003), all five major ethnic groups were represented in all three clusters. CONCLUSION: Chlamydia prevalence in Suriname is high and targeted prevention measures are required. Although ethnic sexual mixing differed between ethnic groups, differences in prevalence between ethnic groups could not be explained by sexual mixing.


Sujet(s)
Chlamydia trachomatis/isolement et purification , Ethnies , Maladies urogénitales de la femme/épidémiologie , Maladies urogénitales de l'homme/épidémiologie , Comportement sexuel , Maladies sexuellement transmissibles/épidémiologie , Adulte , Femelle , Maladies urogénitales de la femme/microbiologie , Humains , Mâle , Maladies urogénitales de l'homme/microbiologie , Prévalence , Maladies sexuellement transmissibles/microbiologie , Suriname/épidémiologie
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