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1.
N Engl J Med ; 386(1): 47-56, 2022 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-34986286

RESUMEN

BACKGROUND: Treponema pallidum subspecies pertenue causes yaws. Strategies to better control, eliminate, and eradicate yaws are needed. METHODS: In an open-label, cluster-randomized, community-based trial conducted in a yaws-endemic area of Papua New Guinea, we randomly assigned 38 wards (i.e., clusters) to receive one round of mass administration of azithromycin followed by two rounds of target treatment of active cases (control group) or three rounds of mass administration of azithromycin (experimental group); round 1 was administered at baseline, round 2 at 6 months, and round 3 at 12 months. The coprimary end points were the prevalence of active cases of yaws, confirmed by polymerase-chain-reaction assay, in the entire trial population and the prevalence of latent yaws, confirmed by serologic testing, in a subgroup of asymptomatic children 1 to 15 years of age; prevalences were measured at 18 months, and the between-group differences were calculated. RESULTS: Of the 38 wards, 19 were randomly assigned to the control group (30,438 persons) and 19 to the experimental group (26,238 persons). A total of 24,848 doses of azithromycin were administered in the control group (22,033 were given to the participants at round 1 and 207 and 2608 were given to the participants with yaws-like lesions and their contacts, respectively, at rounds 2 and 3 [combined]), and 59,852 doses were administered in the experimental group. At 18 months, the prevalence of active yaws had decreased from 0.46% (102 of 22,033 persons) at baseline to 0.16% (47 of 29,954 persons) in the control group and from 0.43% (87 of 20,331 persons) at baseline to 0.04% (10 of 25,987 persons) in the experimental group (relative risk adjusted for clustering, 4.08; 95% confidence interval [CI], 1.90 to 8.76). The prevalence of other infectious ulcers decreased to a similar extent in the two treatment groups. The prevalence of latent yaws at 18 months was 6.54% (95% CI, 5.00 to 8.08) among 994 children in the control group and 3.28% (95% CI, 2.14 to 4.42) among 945 children in the experimental group (relative risk adjusted for clustering and age, 2.03; 95% CI, 1.12 to 3.70). Three cases of yaws with resistance to macrolides were found in the experimental group. CONCLUSIONS: The reduction in the community prevalence of yaws was greater with three rounds of mass administration of azithromycin at 6-month intervals than with one round of mass administration of azithromycin followed by two rounds of targeted treatment. Monitoring for the emergence and spread of antimicrobial resistance is needed. (Funded by Fundació "la Caixa" and others; ClinicalTrials.gov number, NCT03490123.).


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Administración Masiva de Medicamentos , Buba/tratamiento farmacológico , Adolescente , Niño , Preescolar , Farmacorresistencia Bacteriana , Femenino , Haemophilus ducreyi/aislamiento & purificación , Humanos , Lactante , Masculino , Papúa Nueva Guinea/epidemiología , Reacción en Cadena de la Polimerasa , Prevalencia , Úlcera Cutánea/microbiología , Treponema/aislamiento & purificación , Buba/epidemiología
2.
Emerg Infect Dis ; 26(6): 1283-1286, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32441635

RESUMEN

Yaws-like lesions are widely reported in wild African great apes, yet the causative agent has not been confirmed in affected animals. We describe yaws-like lesions in a wild chimpanzee in Guinea for which we demonstrate infection with Treponema pallidum subsp. pertenue. Assessing the conservation implications of this pathogen requires further research.


Asunto(s)
Buba , Animales , Guinea/epidemiología , Pan troglodytes , Treponema , Treponema pallidum/genética , Buba/epidemiología , Buba/veterinaria
3.
Emerg Infect Dis ; 26(11): 2685-2693, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33079046

RESUMEN

Yaws is a neglected tropical disease targeted for eradication by 2030. To achieve eradication, finding and treating asymptomatic infections as well as clinical cases is crucial. The proposed plan, the Morges strategy, involves rounds of total community treatment (i.e., treating the whole population) and total targeted treatment (TTT) (i.e., treating clinical cases and contacts). However, modeling and empirical work suggests asymptomatic infections often are not found in the same households as clinical cases, reducing the utility of household-based contact tracing for a TTT strategy. We use a model fitted to data from the Solomon Islands to predict the likelihood of elimination of transmission under different intervention schemes and levels of systematic nontreatment resulting from the intervention. Our results indicate that implementing additional treatment rounds through total community treatment is more effective than conducting additional rounds of treatment of at-risk persons through TTT.


Asunto(s)
Erradicación de la Enfermedad , Buba , Trazado de Contacto , Humanos , Melanesia , Modelos Teóricos , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/epidemiología , Enfermedades Desatendidas/prevención & control , Treponema pallidum , Buba/tratamiento farmacológico , Buba/epidemiología , Buba/prevención & control
4.
BMC Infect Dis ; 20(1): 392, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32493291

RESUMEN

BACKGROUND: The first yaws eradication campaign reduced the prevalence of yaws by 95%. In recent years, however, yaws has reemerged and is currently subject to a second, ongoing eradication campaign. Yet, the epidemiological status of Tanzania and 75 other countries with a known history of human yaws is currently unknown. Contrary to the situation in humans in Tanzania, recent infection of nonhuman primates (NHPs) with the yaws bacterium Treponema pallidum subsp. pertenue (TPE) have been reported. In this study, we consider a One Health approach to investigate yaws and describe skin ulcers and corresponding T. pallidum serology results among children living in the Tarangire-Manyara ecosystem, an area with increasing wildlife-human interaction in northern Tanzania. METHODS: To investigate human yaws in Tanzania, we conducted a cross-sectional study to screen and interview skin-ulcerated children aged 6 to 15 years, who live in close proximity to two national parks with high numbers of naturally TPE-infected monkeys. Serum samples from children with skin ulcers were tested for antibodies against the bacterium using a treponemal (Treponema pallidum Particle Agglutination assay) and a non-treponemal (Rapid Plasma Reagin) test. RESULTS: A total of 186 children aged between 6 and 15 years (boys: 10.7 ± 2.1 (mean ± SD), N = 132; girls: 10.9 ± 2.0 (mean ± SD), N = 54) were enrolled. Seven children were sampled at health care facilities and 179 at primary schools. 38 children (20.4%) reported active participation in bushmeat hunting and consumption and 26 (13.9%) reported at least one physical contact with a NHP. None of the lesions seen were pathognomonic for yaws. Two children tested positive for treponemal antibodies (1.2%) in the treponemal test, but remained negative in the non-treponemal test. CONCLUSIONS: We found no serological evidence of yaws among children in the Tarangire-Manyara ecosystem. Nevertheless, the close genetic relationship of human and NHPs infecting TPE strains should lead to contact prevention with infected NHPs. Further research investigations are warranted to study the causes and possible prevention measures of spontaneous chronic ulcers among children in rural Tanzania and to certify that the country is free from human yaws.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Úlcera Cutánea/patología , Treponema pallidum/inmunología , Buba/patología , Adolescente , Animales , Niño , Estudios Transversales , Ecosistema , Femenino , Haplorrinos , Humanos , Masculino , Prevalencia , Enfermedades de los Primates/microbiología , Enfermedades de los Primates/patología , Úlcera Cutánea/sangre , Úlcera Cutánea/microbiología , Encuestas y Cuestionarios , Tanzanía/epidemiología , Treponema pallidum/aislamiento & purificación , Buba/epidemiología , Buba/microbiología
5.
BMC Public Health ; 20(1): 517, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32303204

RESUMEN

BACKGROUND: Neglected tropical diseases (NTDs) comprise 20 communicable diseases that are prevalent in rural poor and remote communities with less access to the health system. For effective and efficient control, the WHO recommends that affected countries implement integrated control interventions that take into account the different co-endemic NTDs in the same community. However, implementing these integrated interventions involving several diseases with different etiologies, requiring different control approaches and driven by different vertical programs, remains a challenge. We report here the results and lessons learned from a pilot test of this integrated approach based on integrated screening of skin diseases in three co-endemic health districts of Côte d'Ivoire, a West African country endemic for Buruli ulcer, leprosy and yaw. METHOD: This cross-sectional study took place from April 2016 to March 2017 in 3 districts of Côte d'Ivoire co-endemic for BU, leprosy and yaws. The study was carried out in 6 stages: identification of potentially co-endemic communities; stakeholder training; social mobilization; mobile medical consultations; case detection and management; and a review meeting. RESULTS: We included in the study all patients with skin signs and symptoms at the screening stage who voluntarily accepted screening. In total, 2310 persons screened had skin lesions at the screening stage. Among them, 07 cases were diagnosed with Buruli ulcer. There were 30 leprosy cases and 15 yaws detected. Other types of ulcerations and skin conditions have been identified and represent the majority of cases detected. We learned from this pilot experience that integration can be successfully implemented in co-endemic communities in Côte d'Ivoire. Health workers are motivated and available to implement integrated interventions instead of interventions focused on a single disease. However, it is essential to provide capacity building, a minimum of drugs and consumables for the care of the patients identified, as well as follow-up of identified patients, including those with other skin conditions. CONCLUSIONS: The results of this study show that the integration of activities can be successfully implemented in co-endemic communities under the condition of staff capacity building and minimal care of identified patients.


Asunto(s)
Úlcera de Buruli/epidemiología , Lepra/epidemiología , Tamizaje Masivo/métodos , Mycobacterium leprae , Mycobacterium ulcerans , Enfermedades Desatendidas/epidemiología , Treponema pallidum/inmunología , Buba/epidemiología , Adolescente , Adulto , Anciano , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/microbiología , Niño , Côte d'Ivoire/epidemiología , Estudios Transversales , Enfermedades Endémicas , Femenino , Humanos , Lepra/diagnóstico , Lepra/microbiología , Masculino , Persona de Mediana Edad , Enfermedades Desatendidas/diagnóstico , Enfermedades Desatendidas/microbiología , Proyectos Piloto , Prevalencia , Población Rural , Buba/diagnóstico , Buba/microbiología , Adulto Joven
6.
J Trop Pediatr ; 66(6): 583-588, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32361735

RESUMEN

INTRODUCTION: Congenital syphilis remains a significant cause of newborn mortality and long-term neurodevelopmental problems in some low- and middle-income countries. This study was done in Honiara, Solomon Islands to determine the incidence of babies born to mothers with a positive venereal disease research laboratory (VDRL) test and a positive Treponema pallidum haemagglutination assay (TPHA); to determine the VDRL status of newborns and features of congenital syphilis; and to estimate the proportion of stillbirths associated with syphilis. METHODOLOGY: All neonates born to VDRL-positive mothers, including stillbirths were included between April and July 2019. Neonates were examined, investigated and treated. RESULTS: Among 1534 consecutive births, 1469 were live births and 65 (4.2%) were stillbirths. One hundred and forty-three neonates were born to VDRL-positive mothers: 130 (90.1%) were live infants and 13 (8.9%) stillbirths. Of the 130 VDRL-exposed live-born infants, 72 (55%) had reactive VDRL and a positive TPHA and 7 (9.7%) had clinical signs of congenital syphilis. Five of the infants with clinical signs of syphilis infection had a 4-fold higher VDRL titre than their mother. Four infants of VDRL-positive mothers died during admission, all of whom had clinical signs of syphilis. Ninety percent of affected infants were born to mothers who were not treated or only partially treated during pregnancy. CONCLUSIONS: In this study, 1:210 live-born babies had clinical and serological evidence of congenital syphilis, and evidence of Treponema infection was found disproportionately in stillbirths. In a setting where Treponema infections are common, an empirical approach to prevention may be needed.


Asunto(s)
Mortalidad Infantil , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Mortinato , Sífilis Congénita/diagnóstico , Treponema pallidum/aislamiento & purificación , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Melanesia , Penicilinas/uso terapéutico , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Sífilis/diagnóstico , Sífilis/tratamiento farmacológico , Sífilis/epidemiología , Serodiagnóstico de la Sífilis , Sífilis Congénita/tratamiento farmacológico , Sífilis Congénita/mortalidad , Tetraciclina/uso terapéutico , Resultado del Tratamiento , Treponema pallidum/inmunología , Buba/epidemiología
7.
Lancet ; 391(10130): 1599-1607, 2018 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-29428183

RESUMEN

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. FUNDING: ISDIN laboratories, Newcrest Mining Limited, and US Public Health Service National Institutes of Health.


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Enfermedades Transmisibles Emergentes/tratamiento farmacológico , Administración Masiva de Medicamentos , Buba/tratamiento farmacológico , Adolescente , Niño , Preescolar , Enfermedades Transmisibles Emergentes/epidemiología , Erradicación de la Enfermedad , Farmacorresistencia Bacteriana/genética , Femenino , Variación Genética , Humanos , Lactante , Estudios Longitudinales , Masculino , Papúa Nueva Guinea/epidemiología , Reacción en Cadena de la Polimerasa , Prevalencia , ARN Ribosómico 23S/genética , Resultado del Tratamiento , Treponema pallidum/genética , Buba/epidemiología , Buba/prevención & control
8.
Am J Epidemiol ; 187(4): 837-844, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29140407

RESUMEN

Yaws is a disabling bacterial infection found primarily in warm and humid tropical areas. The World Health Organization strategy mandates an initial round of total community treatment (TCT) with single-dose azithromycin followed either by further TCT or active case-finding and treatment of cases and their contacts (the Morges strategy). We sought to investigate the effectiveness of the Morges strategy. We employed a stochastic household model to study the transmission of infection using data collected from a pre-TCT survey conducted in the Solomon Islands. We used this model to assess the proportion of asymptomatic infections that occurred in households without active cases. This analysis indicated that targeted treatment of cases and their household contacts would miss a large fraction of asymptomatic infections (65%-100%). This fraction was actually higher at lower prevalences. Even assuming that all active cases and their households were successfully treated, our analysis demonstrated that at all prevalences present in the data set, up to 90% of (active and asymptomatic) infections would not be treated under household-based contact tracing. Mapping was undertaken as part of the study "Epidemiology of Yaws in the Solomon Islands and the Impact of a Trachoma Control Programme," in September-October 2013.


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Trazado de Contacto/estadística & datos numéricos , Buba/tratamiento farmacológico , Buba/epidemiología , Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Control de Enfermedades Transmisibles/métodos , Control de Enfermedades Transmisibles/estadística & datos numéricos , Femenino , Humanos , Masculino , Melanesia , Modelos Estadísticos , Buba/transmisión
9.
N Engl J Med ; 372(8): 703-10, 2015 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-25693010

RESUMEN

BACKGROUND: Mass treatment with azithromycin is a central component of the new World Health Organization (WHO) strategy to eradicate yaws. Empirical data on the effectiveness of the strategy are required as a prerequisite for worldwide implementation of the plan. METHODS: We performed repeated clinical surveys for active yaws, serologic surveys for latent yaws, and molecular analyses to determine the cause of skin ulcers and identify macrolide-resistant mutations before and 6 and 12 months after mass treatment with azithromycin on a Papua New Guinean island on which yaws was endemic. Primary-outcome indicators were the prevalence of serologically confirmed active infectious yaws in the entire population and the prevalence of latent yaws with high-titer seroreactivity in a subgroup of children 1 to 15 years of age. RESULTS: At baseline, 13,302 of 16,092 residents (82.7%) received one oral dose of azithromycin. The prevalence of active infectious yaws was reduced from 2.4% before mass treatment to 0.3% at 12 months (difference, 2.1 percentage points; P<0.001). The prevalence of high-titer latent yaws among children was reduced from 18.3% to 6.5% (difference, 11.8 percentage points; P<0.001) with a near-absence of high-titer seroreactivity in children 1 to 5 years of age. Adverse events identified within 1 week after administration of the medication occurred in approximately 17% of the participants, included nausea, diarrhea, and vomiting, and were mild in severity. No evidence of emergence of resistance to macrolides against Treponema pallidum subspecies pertenue was seen. CONCLUSIONS: The prevalence of active and latent yaws infection fell rapidly and substantially 12 months after high-coverage mass treatment with azithromycin, with the reduction perhaps aided by subsequent activities to identify and treat new cases of yaws. Our results support the WHO strategy for the eradication of yaws. (Funded by Newcrest Mining and International SOS; YESA-13 ClinicalTrials.gov number, NCT01955252.).


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Treponema pallidum/aislamiento & purificación , Buba/tratamiento farmacológico , Adolescente , Adulto , Distribución por Edad , Antibacterianos/efectos adversos , Azitromicina/efectos adversos , Chancroide/epidemiología , Niño , Preescolar , Estudios Transversales , Farmacorresistencia Bacteriana/genética , Enfermedades Endémicas , Haemophilus ducreyi/aislamiento & purificación , Humanos , Lactante , Papúa Nueva Guinea/epidemiología , Reacción en Cadena de la Polimerasa , Prevalencia , Treponema pallidum/genética , Buba/diagnóstico , Buba/epidemiología , Adulto Joven
10.
Emerg Infect Dis ; 23(1): 22-28, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27983500

RESUMEN

Yaws is targeted for eradication by 2020. The mainstay of the eradication strategy is mass treatment followed by case finding. Modeling has been used to inform programmatic requirements for other neglected tropical diseases and could provide insights into yaws eradication. We developed a model of yaws transmission varying the coverage and number of rounds of treatment. The estimated number of cases arising from an index case (basic reproduction number [R0]) ranged from 1.08 to 3.32. To have 80% probability of achieving eradication, 8 rounds of treatment with 80% coverage were required at low estimates of R0 (1.45). This requirement increased to 95% at high estimates of R0 (2.47). Extending the treatment interval to 12 months increased requirements at all estimates of R0. At high estimates of R0 with 12 monthly rounds of treatment, no combination of variables achieved eradication. Models should be used to guide the scale-up of yaws eradication.


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Erradicación de la Enfermedad/estadística & datos numéricos , Modelos Estadísticos , Enfermedades Desatendidas/prevención & control , Buba/prevención & control , Simulación por Computador , Erradicación de la Enfermedad/métodos , Femenino , Humanos , Masculino , Cadenas de Markov , Enfermedades Desatendidas/epidemiología , Recurrencia , Treponema pallidum/patogenicidad , Treponema pallidum/fisiología , Clima Tropical , Buba/epidemiología , Buba/transmisión
11.
J Clin Microbiol ; 54(5): 1321-5, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26962086

RESUMEN

WHO has targeted yaws for global eradication by 2020. The program goals are to interrupt the transmission in countries where yaws is endemic and to certify countries as yaws free where yaws was endemic in the past. No new rapid plasmin reagin (RPR) seroreactivity in young children is required for certification of elimination at a country level. We sought to evaluate whether antibody responses to specific treponemal antigens measured in a high-throughput multiplex bead array (MBA) assay differentiate past versus current infection and whether a nontreponemal lipoidal antigen test can be incorporated into the MBA. Serum and dried blood spot specimens collected for yaws surveillance projects in Ghana, Vanuatu, and Papua New Guinea (PNG) were run on MBA to measure antibodies against recombinant p17 (rp17) and treponemal membrane protein A (TmpA) treponemal antigens. Results were compared to standard treponemal laboratory (TPPA or TPHA [TPP(H)A]) and quantitative RPR test data. Of 589 specimens, 241 were TPP(H)A(+)/RPR(+), 88 were TPP(H)A(+)/RPR(-), 6 were TPP(H)A(-)/RPR(+), and 254 were negative for both tests. Compared to TPP(H)A, reactive concordance of rp17 was 93.7%, while reactive concordance of TmpA was only 81.9%. TmpA-specific reactivity showed good correlation with RPR titers (R(2) = 0.41; P < 0.0001). IgG responses to the lipoidal antigen used in RPR testing (cardiolipin) were not detected in the MBA. Our results suggest that TmpA can be used as a treponemal antigen marker for recent or active infection and potentially replace RPR in a high-throughput multiplex tool for large-scale yaws surveillance.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Monitoreo Epidemiológico , Pruebas Serológicas/métodos , Buba/diagnóstico , Buba/epidemiología , Adolescente , Niño , Preescolar , Femenino , Ghana , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Lactante , Masculino , Papúa Nueva Guinea , Vanuatu
12.
Curr Opin Infect Dis ; 29(1): 52-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26658654

RESUMEN

PURPOSE OF REVIEW: This article provides an overview of the biology, epidemiology, clinical features, diagnostic tests, and treatment of Haemophilus ducreyi infection, with special reference to the decline of chancroid and the recent emergence of H. ducreyi as a pathogen responsible for chronic limb ulceration clinically similar to yaws. RECENT FINDINGS: Chancroid has declined in importance as a sexually transmitted infection in most countries where it was previously endemic. Chancroid may be caused by either class I or class II H. ducreyi isolates; these two classes diverged from each other approximately 1.95 million years ago. H. ducreyi has recently emerged as a cause of chronic skin ulceration in the Pacific region and Africa. Based on sequencing of whole genomes and defined genetic loci, it appears that the cutaneous H. ducreyi strains diverged from the class I genital strains relatively recently. SUMMARY: H. ducreyi should be considered as a major cause of chronic limb ulceration in both adults and children and appropriate molecular diagnostic assays are required to determine ulcer aetiology. The high prevalence of H. ducreyi-related cutaneous ulceration in yaws-endemic countries has challenged the validity of observational surveys to monitor the effectiveness of the WHO's yaws eradication campaign.


Asunto(s)
Chancroide/patología , Haemophilus ducreyi/patogenicidad , Enfermedades de Transmisión Sexual/microbiología , Úlcera Cutánea/microbiología , Buba/epidemiología , África/epidemiología , Chancroide/epidemiología , Chancroide/microbiología , Chancroide/prevención & control , Enfermedades Endémicas , Pruebas de Hemaglutinación , Humanos , Islas del Pacífico/epidemiología , Prevalencia , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Úlcera Cutánea/patología
13.
BMC Infect Dis ; 16(1): 745, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27938337

RESUMEN

BACKGROUND: Use of treponemal tests to screen for syphilis (caused by Treponema pallidum pallidum) poses challenges with infection status classification, especially in settings where other treponemal infections are endemic. This study aimed to determine the validity of the syphilis surveillance testing strategy implemented since 2004 using two treponemal tests, and estimate the seroprevalence of active syphilis infection in Ghana where yaws (caused by Treponema pallidum pertenue) is endemic. METHODS: We retested sera from the 2007 HIV sentinel survey (HSS) using a traditional algorithm, quantitative rapid plasma reagin test followed by qualitative Treponema pallidum haemagglutination assay. The adjusted seroprevalence of active syphilis was calculated by applying the proportions of active syphilis within identified categories of HSS samples during the retesting, to the entire population of HSS samples. The 95% confidence intervals (CIs) were calculated for each proportion, and the t-test was used to assess differences in proportions. RESULTS: Of 2,214 samples that were retested, 203 (9.2%) had active syphilis infection, 21 (0.9%) were biological false reactions, 640 (28.9%) were past or treated syphilis infections, and 1,350 (61%) were uninfected. The current syphilis testing strategy overestimated the seroprevalence of active syphilis infection by a third (HSS versus traditional algorithm: 6.0% (95% CI: 5.6-6.3) vs. 4.5% (95% CI: 4.2-4.8); p < 0.001), and had low positive predictive value (16.8%) for detecting active syphilis infection. More than half (51.9%) of HSS syphilis positive cases were actually past/treated treponemal infections, possibly previous exposure to yaws. CONCLUSION: There is an urgent need to review the current syphilis sentinel surveillance testing strategy in Ghana in the context of concurrent endemic treponematoses, to better inform policy.


Asunto(s)
Sífilis/diagnóstico , Sífilis/epidemiología , Adolescente , Adulto , Algoritmos , Femenino , Ghana/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Vigilancia de Guardia , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Serodiagnóstico de la Sífilis/métodos , Treponema pallidum/patogenicidad , Infecciones por Treponema/tratamiento farmacológico , Buba/epidemiología , Adulto Joven
14.
Br Med Bull ; 113: 91-100, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25525120

RESUMEN

INTRODUCTION: Yaws, caused by Treponema pallidum ssp. pertenue, is endemic in parts of West Africa, Southeast Asia and the Pacific. The WHO has launched a campaign based on mass treatment with azithromycin, to eradicate yaws by 2020. SOURCES OF DATA: We reviewed published data, surveillance data and data presented at yaws eradication meetings. AREAS OF AGREEMENT: Azithromycin is now the preferred agent for treating yaws. Point-of-care tests have demonstrated their value in yaws. AREAS OF CONTROVERSY: There is limited data from 76 countries, which previously reported yaws. Different doses of azithromycin are used in community mass treatment for yaws and trachoma. GROWING POINTS: Yaws eradication appears an achievable goal. The programme will require considerable support from partners across health and development sectors. AREAS TIMELY FOR DEVELOPING RESEARCH: Studies to complete baseline mapping, integrate diagnostic tests into surveillance and assess the impact of community mass treatment with azithromycin are ongoing.


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Erradicación de la Enfermedad , Treponema pallidum/efectos de los fármacos , Buba , Antibacterianos/economía , Azitromicina/economía , Análisis Costo-Beneficio , Erradicación de la Enfermedad/economía , Erradicación de la Enfermedad/métodos , Humanos , Desarrollo de Programa , Vigilancia de Guardia , Buba/tratamiento farmacológico , Buba/epidemiología , Buba/prevención & control
15.
Indian J Med Res ; 141(5): 608-13, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26139778

RESUMEN

Yaws, a non-venereal treponematosis, affecting primarily the tribal populations, has been considered historically as one of the most neglected tropical diseases in the world. In 1996, India piloted an initiative to eradicate yaws based on a strategy consisting of active case finding through house-to-house search and treatment of cases and their contacts with long acting penicillin. Thereafter, the campaign implemented in all 51 endemic districts in 10 states of the country led to the achievement of a yaws-free status in 2004. In the post-elimination phase, surveillance activities accompanied by serological surveys were continued in the erstwhile endemic districts. These surveys carried out among children between the age of 1-5 yr, further confirmed the absence of community transmission in the country. The experience of India demonstrates that yaws can be eradicated in all endemic countries of Africa and Asia, provided that political commitment can be mobilized and community level activities sustained until the goal is achieved.


Asunto(s)
Treponema pallidum/patogenicidad , Infecciones por Treponema/epidemiología , Buba/epidemiología , Humanos , India/epidemiología , Grupos de Población , Infecciones por Treponema/microbiología , Buba/microbiología
16.
Lancet ; 381(9868): 763-73, 2013 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-23415015

RESUMEN

Yaws is an infectious disease caused by Treponema pallidum pertenue-a bacterium that closely resembles the causative agent of syphilis-and is spread by skin-to-skin contact in humid tropical regions. Yaws causes disfiguring, and sometimes painful lesions of the skin and bones. As with syphilis, clinical manifestations can be divided into three stages; however, unlike syphilis, mother-to-child transmission does not occur. A major campaign to eradicate yaws in the 1950s and 1960s, by mass treatment of affected communities with longacting, injectable penicillin, reduced the number of cases by 95% worldwide, but yaws has reappeared in recent years in Africa, Asia, and the western Pacific. In 2012, one oral dose of azithromycin was shown to be as effective as intramuscular penicillin in the treatment of the disease, and WHO launched a new initiative to eradicate yaws by 2020.


Asunto(s)
Buba , Antibacterianos/uso terapéutico , Progresión de la Enfermedad , Humanos , Treponema pallidum , Buba/diagnóstico , Buba/tratamiento farmacológico , Buba/epidemiología , Buba/etiología , Buba/microbiología , Buba/patología , Buba/prevención & control
17.
PLoS Negl Trop Dis ; 18(1): e0011831, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38166151

RESUMEN

Yaws is an endemic disease caused by Treponema pallidum subsp. pertenue (TPE) that primarily affects children in rural regions of the tropics. The endemic character of yaws infections and the expected exclusive reservoir of TPE in humans opened a new opportunity to start a yaws eradication campaign. We have developed a multi-locus sequence typing (MLST) scheme for TPE isolates combining the previously published (TP0548, TP0488) and new (TP0858) chromosomal loci, and we compared this typing scheme to the two previously published MLST schemes. We applied this scheme to TPE-containing clinical isolates obtained during a mass drug administration study performed in the Namatanai District of Papua New Guinea between June 2018 and December 2019. Of 1081 samples collected, 302 (28.5%) tested positive for TPE DNA, from which 255 (84.4%) were fully typed. The TPE PCR-positivity in swab samples was higher in younger patients, patients with single ulcers, first ulcer episodes, and with ulcer duration less than six months. Non-treponemal serological test positivity correlated better with PCR positivity compared to treponema-specific serological tests. The MLST revealed a low level of genetic diversity among infecting TPE isolates, represented by just three distinct genotypes (JE11, SE22, and TE13). Two previously used typing schemes revealed similar typing resolutions. Two new alleles (one in TP0858 and one in TP0136) were shown to arise by intragenomic recombination/deletion events. Compared to samples genotyped as JE11, the minor genotypes (TE13 and SE22) were more frequently detected in samples from patients with two or more ulcers and patients with higher values of specific TP serological tests. Moreover, the A2058G mutation in the 23S rRNA genes of three JE11 isolates was found, resulting in azithromycin resistance.


Asunto(s)
Treponema pallidum , Buba , Niño , Humanos , Treponema pallidum/genética , Úlcera , Tipificación de Secuencias Multilocus , Buba/epidemiología , Papúa Nueva Guinea/epidemiología , Treponema/genética , Mutación , Genotipo
18.
PLoS Negl Trop Dis ; 18(6): e0012224, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38900827

RESUMEN

Yaws, caused by Treponema pallidum ssp. pertenue, remains a significant public health concern in tropical regions of West Africa and the South Pacific, primarily affecting children in remote areas with limited access to hygiene and sanitation. In this study, conducted in three endemic countries of West Africa where yaws remains a significant public health concern (Ghana, Cameroon, and Côte d'Ivoire), we aimed to assess the knowledge, attitudes, and practices related to yaws among community members, community health workers (CHWs), and traditional healers. The study revealed variations in the perception of causes of yaws among community members: the majority or participants in Ghana attributed yaws to germs (60.2%); in Cameroon the most reported form of transmission was contact with or drinking infected water sources (44.6%); and in Côte d'Ivoire both of these answers were also the most prevalent (60.3% germs and 93.% water sources). A substantial proportion of participants in Côte d'Ivoire also associated yaws with witchcraft and divine punishment (44.8%). Only a small proportion of individuals in Ghana and Côte d'Ivoire correctly identified contact with an infected person as a form of transmission (11.9% and 20.7%, respectively) and less than half in Cameroon (42.6%), although more than 98% of all participants reported avoidance behaviours towards yaws infected people due to fear of getting infected. Most participants expressed a preference for seeking care at hospitals (49.2%, 60.6%, 86.2%) or health care professionals including doctors and nurses (58.5%, 41,5% and 17.2%) if they were diagnosed with yaws, although a quarter of participants in Côte d'Ivoire also sought support from traditional healers. The CHWs interviewed were generally well-trained on yaws causes and treatment options, although they often reported low availability of treatment and diagnostic tests for yaws. Our findings underscore the need for community education, awareness campaigns, ongoing CHW training, and improved access to yaws treatment and diagnostic resources. The data also suggest that collaboration with traditional healers, who usually hold a highly esteemed position in the society, such as giving training on yaws causes and transmission or exchanging knowledge on treatment options, could be beneficial in certain regions, particularly in Côte d'Ivoire.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Buba , Humanos , Buba/epidemiología , Camerún/epidemiología , Côte d'Ivoire/epidemiología , Ghana/epidemiología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Adulto Joven , Adolescente , Agentes Comunitarios de Salud/psicología , Anciano , Treponema pallidum
19.
PLoS One ; 19(5): e0295088, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38776332

RESUMEN

Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws and elimination of syphilis, these two diseases are still present in Ghana. The aetiological agents of both diseases, two Treponema pallidum subspecies, are genetically similar. This study aimed to assess the prevalence of these treponematoses and the occurrence of pathogens causing similar skin lesions in the Ashanti region of Ghana. A point-of-care test was used to determine the seroprevalence of the treponematoses. Both yaws and syphilis were identified in the Ashanti region of Ghana. Multiplex PCR was used to identify treponemes and other pathogens that cause similar skin lesions. The results indicated that the seroprevalences of T. pallidum in individuals with yaws-like and syphilis-like lesions were 17.2% and 10.8%, respectively. Multiplex PCR results showed that 9.1%, 1.8% and 0.9% of yaws-like lesions were positive for Haemophilus ducreyi, herpes simplex virus-1 (HSV-1) and T. pallidum respectively. Among syphilis-like lesions, 28.3% were positive for herpes simplex virus -2 (HSV-2) by PCR. To our knowledge, this is the first time HSV-I and HSV-2 have been reported from yaws-like and syphilis-like lesions, respectively, in Ghana. The presence of other organisms apart from T. pallidum in yaws-like and syphilis-like lesions could impede the total healing of these lesions and the full recovery of patients. This may complicate efforts to achieve yaws eradication by 2030 and the elimination of syphilis and warrants updated empirical treatment guidelines for skin ulcer diseases.


Asunto(s)
Haemophilus ducreyi , Sífilis , Treponema pallidum , Buba , Humanos , Ghana/epidemiología , Buba/epidemiología , Buba/microbiología , Sífilis/epidemiología , Sífilis/microbiología , Femenino , Adulto , Masculino , Haemophilus ducreyi/aislamiento & purificación , Haemophilus ducreyi/genética , Adolescente , Prevalencia , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación , Niño , Adulto Joven , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/aislamiento & purificación , Persona de Mediana Edad , Estudios Seroepidemiológicos , Piel/microbiología , Piel/patología , Piel/virología , Preescolar , Infecciones por Treponema/epidemiología , Infecciones por Treponema/microbiología
20.
PLoS Negl Trop Dis ; 18(8): e0012398, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39146379

RESUMEN

Haemophilus ducreyi (HD) is an important cause of cutaneous ulcers in several endemic regions, including the Western Pacific Region, especially among children. An HD sequence typing on swab samples taken from 1,081 ulcers in the Namatanai district of Papua New Guinea, during the pilot study for treatment of yaws, has been performed using the Grant typing system. Of the 363 samples that tested positive for the 16S rDNA of HD, the dsrA sequences of 270 samples were determined. Altogether they revealed 8 HD strain types circulating in Namatanai, including seven strain types of Class I (I.3, I.4, I.5, I.9, I.10, I.11, I.12) and one strain of Class II (II.3); four Class I types (I.9, I.10, I.11, I.12) were novel. The southern region of Namatanai (Matalai Rural) was identified as the region with the lowest genotype diversity and with most infections caused by HD Class II. The middle and northern subdistricts were affected mainly by HD Class I. Analysis of patient characteristics revealed that Class II HD infections were more often represented by longer-lasting ulcers than Class I HD infections. An increase in the prevalence of the I.10 strain was found after azithromycin administration compared to the untreated population at baseline likely reflecting higher infectivity of HD Class I, and more specifically strain type I.10.


Asunto(s)
Antibacterianos , Azitromicina , Chancroide , Genotipo , Haemophilus ducreyi , Humanos , Haemophilus ducreyi/genética , Haemophilus ducreyi/aislamiento & purificación , Haemophilus ducreyi/efectos de los fármacos , Azitromicina/uso terapéutico , Papúa Nueva Guinea/epidemiología , Femenino , Masculino , Niño , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Adolescente , Chancroide/microbiología , Chancroide/epidemiología , Chancroide/tratamiento farmacológico , Adulto , Preescolar , Adulto Joven , ARN Ribosómico 16S/genética , Buba/microbiología , Buba/epidemiología , Buba/tratamiento farmacológico , Persona de Mediana Edad , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Proyectos Piloto , Filogenia
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