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1.
N Engl J Med ; 384(5): 417-427, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33289973

RESUMEN

BACKGROUND: Current strategies for preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are limited to nonpharmacologic interventions. Hydroxychloroquine has been proposed as a postexposure therapy to prevent coronavirus disease 2019 (Covid-19), but definitive evidence is lacking. METHODS: We conducted an open-label, cluster-randomized trial involving asymptomatic contacts of patients with polymerase-chain-reaction (PCR)-confirmed Covid-19 in Catalonia, Spain. We randomly assigned clusters of contacts to the hydroxychloroquine group (which received the drug at a dose of 800 mg once, followed by 400 mg daily for 6 days) or to the usual-care group (which received no specific therapy). The primary outcome was PCR-confirmed, symptomatic Covid-19 within 14 days. The secondary outcome was SARS-CoV-2 infection, defined by symptoms compatible with Covid-19 or a positive PCR test regardless of symptoms. Adverse events were assessed for up to 28 days. RESULTS: The analysis included 2314 healthy contacts of 672 index case patients with Covid-19 who were identified between March 17 and April 28, 2020. A total of 1116 contacts were randomly assigned to receive hydroxychloroquine and 1198 to receive usual care. Results were similar in the hydroxychloroquine and usual-care groups with respect to the incidence of PCR-confirmed, symptomatic Covid-19 (5.7% and 6.2%, respectively; risk ratio, 0.86 [95% confidence interval, 0.52 to 1.42]). In addition, hydroxychloroquine was not associated with a lower incidence of SARS-CoV-2 transmission than usual care (18.7% and 17.8%, respectively). The incidence of adverse events was higher in the hydroxychloroquine group than in the usual-care group (56.1% vs. 5.9%), but no treatment-related serious adverse events were reported. CONCLUSIONS: Postexposure therapy with hydroxychloroquine did not prevent SARS-CoV-2 infection or symptomatic Covid-19 in healthy persons exposed to a PCR-positive case patient. (Funded by the crowdfunding campaign YoMeCorono and others; BCN-PEP-CoV2 ClinicalTrials.gov number, NCT04304053.).


Asunto(s)
Antiinfecciosos/uso terapéutico , COVID-19/prevención & control , Hidroxicloroquina/uso terapéutico , SARS-CoV-2 , Adulto , Antiinfecciosos/efectos adversos , COVID-19/transmisión , COVID-19/virología , Transmisión de Enfermedad Infecciosa/prevención & control , Método Doble Ciego , Femenino , Humanos , Hidroxicloroquina/efectos adversos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Insuficiencia del Tratamiento , Carga Viral
2.
Clin Infect Dis ; 68(3): 482-489, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-29917039

RESUMEN

Background: Treponema pallidum subsp pertenue and Haemophilus ducreyi are causative agents of cutaneous ulcer (CU) in yaws-endemic regions in the tropics. However, a significant proportion of CU patients remain polymerase chain reaction (PCR) negative for both bacterial agents. We aimed to identify potential additional etiological agents of CU in a yaws-endemic region. Methods: This population-based cohort study included children in Lihir Island (Papua New Guinea) examined during a yaws eradication campaign in October 2013-October 2014. All consenting patients with atraumatic exudative ulcers of >1 cm diameter were enrolled. Lesional swabs were collected for real-time PCR testing for T. pallidum subsp pertenue and H. ducreyi. We then performed shotgun whole DNA metagenomics sequencing on extracted DNA and taxonomically assigned shotgun sequences using a human microbiome reference. Results: Sequence data were available for 122 samples. Shotgun sequencing showed high classification agreement relative to PCR testing (area under the curve for T. pallidum/H. ducreyi was 0.92/0.85, respectively). Clustering analysis of shotgun data revealed compositional clusters where the dominant species (median relative abundance ranged from 32% to 66%) was H. ducreyi (23% of specimens), T. pallidum subsp pertenue (16%), Streptococcus dysgalactiae (12%), Arcanobacterium haemolyticum (8%), and Corynebacterium diphtheriae (8%). Sample clustering derived from ulcer microbial composition did not show geographical patterns. Conclusions: These data suggest a diverse etiology of skin ulcers in yaws-endemic areas, which may help design more accurate diagnostic tools and more effective antimicrobial treatment approaches to the cutaneous ulcer syndrome.


Asunto(s)
Bacterias/aislamiento & purificación , Enfermedades Cutáneas Bacterianas/epidemiología , Enfermedades Cutáneas Bacterianas/etiología , Úlcera/epidemiología , Úlcera/etiología , Adolescente , Bacterias/clasificación , Bacterias/genética , Niño , Coinfección/epidemiología , Coinfección/etiología , Femenino , Humanos , Masculino , Metagenómica/métodos , Papúa Nueva Guinea/epidemiología , Estudios Prospectivos , Análisis de Secuencia de ADN
3.
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
4.
Clin Infect Dis ; 67(11): 1768-1774, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-29897409

RESUMEN

Background: Together with Treponema pallidum subspecies pertenue, Haemophilus ducreyi is a major cause of exudative cutaneous ulcers (CUs) in children. For H. ducreyi, both class I and class II strains, asymptomatic colonization, and environmental reservoirs have been found in endemic regions, but the epidemiology of this infection is unknown. Methods: Based on published whole-genome sequences of H. ducreyi CU strains, a single-locus typing system was developed and applied to H. ducreyi-positive CU samples obtained prior to, 1 year after, and 2 years after the initiation of a mass drug administration campaign to eradicate CU on Lihir Island in Papua New Guinea. DNA from the CU samples was amplified with class I and class II dsrA-specific primers and sequenced; the samples were classified into dsrA types, which were geospatially mapped. Selection pressure analysis was performed on the dsrA sequences. Results: Thirty-seven samples contained class I sequences, 27 contained class II sequences, and 13 contained both. There were 5 class I and 4 class II types circulating on the island; 3 types accounted for approximately 87% of the strains. The composition and geospatial distribution of the types varied little over time and there was no evidence of selection pressure. Conclusions: Multiple strains of H. ducreyi cause CU on an endemic island and coinfections are common. In contrast to recent findings with T. pallidum pertenue, strain composition is not affected by antibiotic pressure, consistent with environmental reservoirs of H. ducreyi. Such reservoirs must be addressed to achieve eradication of H. ducreyi.


Asunto(s)
Chancroide/epidemiología , Enfermedades Endémicas , Haemophilus ducreyi/clasificación , Úlcera Cutánea/epidemiología , Úlcera Cutánea/microbiología , Técnicas de Tipificación Bacteriana , Chancroide/microbiología , Niño , ADN Bacteriano/genética , Haemophilus ducreyi/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Islas/epidemiología , Administración Masiva de Medicamentos , Tipificación de Secuencias Multilocus , Papúa Nueva Guinea/epidemiología , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Secuenciación Completa del Genoma
5.
Nicotine Tob Res ; 20(6): 674-680, 2018 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-28575495

RESUMEN

Introduction: Exposure to maternal smoking early in life may affect blood pressure (BP) control mechanisms. We examined the association between maternal smoking (before conception, during pregnancy, and 4 years after delivery) and BP in preschool children. Methods: We evaluated 4295 of Generation XXI children, recruited at birth in 2005-2006 and reevaluated at the age of 4. At birth, information was collected by face-to-face interview and additionally abstracted from clinical records. At 4-year follow-up, interviews were performed and children's BP measured. Linear regression models were fitted to estimate the association between maternal smoking and children's BP. Results: Children of smoking mothers presented significantly higher BP levels. After adjustment for maternal education, gestational hypertensive disorders, and child's body mass index, children exposed during pregnancy to maternal smoking presented a higher systolic BP (SBP) z-score (ß = 0.08, 95% confidence interval [CI] 0.04 to 0.14). In crude models, maternal smoking was associated with higher SBP z-score at every assessed period. However, after adjustment, an attenuation of the association estimates occurred (ß = 0.08, 95% CI 0.03 to 0.13 before conception; ß = 0.07, 95%CI 0.02 to 0.12; ß = 0.04, 95%CI -0.02 to 0.10; and ß = 0.06, 95%CI 0.00 to 0.13 for the first, second, and third pregnancy trimesters, respectively; and ß = 0.07, 95%CI 0.02 to 0.12 for current maternal smoking). No significant association was observed for diastolic BP z-score levels. Conclusion: Maternal smoking before, during, and after pregnancy was independently associated with systolic BP z-score in preschool children. This study provides additional evidence to the public health relevance of maternal smoking cessation programs if early cardiovascular health of children is envisaged. Implications: Using observational longitudinal data from the birth cohort Generation XXI, this study showed that exposure to maternal smoking-before pregnancy, during pregnancy, and 4 years after delivery-was associated with a systolic BP-raising effect in children at the age of 4. The findings of this study add an important insight into the need to support maternal smoke-free environments in order to provide long-term cardiovascular benefit, starting as early as possible in life.


Asunto(s)
Presión Sanguínea/fisiología , Conducta Materna/fisiología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Fumar/efectos adversos , Fumar/fisiopatología , Contaminación por Humo de Tabaco/efectos adversos , Adulto , Índice de Masa Corporal , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/diagnóstico , Hipertensión/etiología , Hipertensión/fisiopatología , Estudios Longitudinales , Masculino , Conducta Materna/psicología , Embarazo , Tercer Trimestre del Embarazo/fisiología , Efectos Tardíos de la Exposición Prenatal/diagnóstico , Efectos Tardíos de la Exposición Prenatal/etiología
6.
Clin Infect Dis ; 65(12): 2085-2090, 2017 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-29020192

RESUMEN

BACKGROUND: Haemophilus ducreyi (HD) and Treponema pallidum subspecies pertenue (TP) are major causative agents of cutaneous ulcer (CU) in the tropics. Azithromycin is recommended to treat sexually transmitted HD infections and has good in vitro activity against HD strains from both genital and skin ulcers. We investigated the efficacy of oral single-dose azithromycin on HD-CU. METHODS: We conducted a community-based cohort study in Lihir Island, Papua New Guinea, from October 2014 through May 2016. Consenting patients with skin ulcers >1 cm in diameter were eligible for this study and had collected a lesional swab for polymerase chain reaction (PCR). All participants were treated with single-dose azithromycin (30 mg/kg) and were followed up for assessment of clinical resolution. We retrospectively classified patients according to PCR results into HD, TP, and PCR-negative groups. The primary endpoint was healing rates of HD-CU at 14 days after treatment. RESULTS: We obtained full outcome data from 246 patients; 131 (53.3%) were HD PCR positive, 37 (15.0%) were TP positive, and 78 (31.7%) were negative for all tests. Healing rates were 88.5% (95% confidence interval [CI], .82-.93) in the HD group, 78.4% [95% CI, .63-.89] in the TP group, and 74.4% (95% CI, .64-.83) in the PCR-negative group. If we included the participants with improved ulcers, the healing rates increased to 94.7%, 97.3%, and 89.7% respectively. HD cases classified as not healed all converted to HD-negative PCR. CONCLUSIONS: Based upon clinical resolution and PCR conversion to HD negative, a single oral dose of azithromycin is efficacious for the treatment of HD-CU. These results have implications for the treatment of individual patients and for the use of antibiotics in public health strategies to control CU in the tropics.


Asunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Azitromicina/administración & dosificación , Azitromicina/uso terapéutico , Haemophilus ducreyi/efectos de los fármacos , Úlcera Cutánea/tratamiento farmacológico , Administración Oral , Adolescente , Azitromicina/efectos adversos , Chancroide/epidemiología , Chancroide/microbiología , Niño , Estudios de Cohortes , Femenino , Haemophilus ducreyi/genética , Humanos , Masculino , Papúa Nueva Guinea/epidemiología , Reacción en Cadena de la Polimerasa , Salud Pública , Estudios Retrospectivos , Úlcera Cutánea/microbiología , Resultado del Tratamiento , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación
7.
Emerg Infect Dis ; 22(1): 1-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26694983

RESUMEN

The global epidemiology of Haemophilus ducreyi infections is poorly documented because of difficulties in confirming microbiological diagnoses. We evaluated published data on the proportion of genital and nongenital skin ulcers caused by H. ducreyi before and after introduction of syndromic management for genital ulcer disease (GUD). Before 2000, the proportion of GUD caused by H. ducreyi ranged from 0.0% to 69.0% (35 studies in 25 countries). After 2000, the proportion ranged from 0.0% to 15.0% (14 studies in 13 countries). In contrast, H. ducreyi has been recently identified as a causative agent of skin ulcers in children in the tropical regions; proportions ranged from 9.0% to 60.0% (6 studies in 4 countries). We conclude that, although there has been a sustained reduction in the proportion of GUD caused by H. ducreyi, this bacterium is increasingly recognized as a major cause of nongenital cutaneous ulcers.


Asunto(s)
Chancroide/epidemiología , Haemophilus ducreyi/patogenicidad , Úlcera Cutánea/microbiología , Adulto , Niño , Femenino , Humanos , Masculino
8.
Acta Trop ; 256: 107254, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38759832

RESUMEN

The etiological agent of yaws is the spirochete Treponema pallidum (TP) subsp. pertenue (TPE) and infects the children of Papua New Guinea, causing ulcerative skin lesions that impairs normal growth and development. Closely related strains of Treponema pallidum subsp. pertenue, JE11, and TE13 were detected in an ulcer biospecimen derived from a 5-year-old yaws patient. Cloning experiments validated the presence of two distinct but similar genotypes, namely TE13 and JE11, co-occurring within a single host. While coinfection with highly related TPE strains has only limited epidemiological and clinical relevance, this is the first documented coinfection with genetically distinct TP strains in a single patient. Similar coinfections in the past were explained by the existence of over a dozen recombinant loci present in the TP genomes as a result of inter-strain or inter-subspecies recombination events following an anticipated scenario of TP coinfection, i.e., uptake of foreign DNA and DNA recombination.


Asunto(s)
Coinfección , Genotipo , Treponema pallidum , Buba , Humanos , Buba/microbiología , Coinfección/microbiología , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación , Treponema pallidum/clasificación , Papúa Nueva Guinea , Preescolar , Filogenia , Masculino , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Treponema
9.
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
10.
Lancet Microbe ; 4(12): e994-e1004, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37827185

RESUMEN

BACKGROUND: The increasing incidence of syphilis and the limitations of first-line treatment with penicillin, particularly in neurosyphilis, neonatal syphilis, and pregnancy, highlight the need to expand the therapeutic repertoire for effective management of this disease. We assessed the in-vitro efficacy of 18 antibiotics from several classes on Treponema pallidum subspecies pallidum (T pallidum), the syphilis bacteria. METHODS: Using the in-vitro culture system for T pallidum, we exposed the pathogen to a concentration range of each tested antibiotic. After a 7-day incubation, the treponemal burden was evaluated by quantitative PCR targeting the T pallidum tp0574 gene. The primary outcome was the minimum inhibitory concentration (MIC) at which the quantitative PCR values were not significantly higher than the inoculum wells. We also investigated the susceptibility of macrolide-resistant strains to high concentrations of azithromycin, and the possibility of developing resistance to linezolid, a proposed candidate for syphilis treatment. FINDINGS: Amoxicillin, ceftriaxone, several oral cephalosporins, tedizolid, and dalbavancin exhibited anti-treponemal activity at concentrations achievable in human plasma following regular dosing regimens. The experiments revealed a MIC for amoxicillin at 0·02 mg/L, ceftriaxone at 0·0025 mg/L, cephalexin at 0·25 mg/L, cefetamet and cefixime at 0·0313 mg/L, cefuroxime at 0·0156 mg/L, tedizolid at 0·0625 mg/L, spectinomycin at 0·1 mg/L, and dalbavancin at 0·125 mg/L. The MIC for zoliflodacin and balofloxacin was 2 mg/L. Ertapenem, isoniazid, pyrazinamide, and metronidazole had either a poor or no effect. Azithromycin concentrations up to 2 mg/L (64 times the MIC) were ineffective against strains carrying mutations associated to macrolide resistance. Exposure to subtherapeutic doses of linezolid for 10 weeks did not induce phenotypic or genotypic resistance. INTERPRETATION: Cephalosporins and oxazolidinones are potential candidates for expanding the current therapeutic repertoire for syphilis. Our findings warrant testing efficacy in animal models and, if successful, clinical assessment of efficacy. FUNDING: European Research Council.


Asunto(s)
Sífilis , Treponema pallidum , Animales , Recién Nacido , Humanos , Treponema pallidum/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Azitromicina/farmacología , Azitromicina/uso terapéutico , Sífilis/tratamiento farmacológico , Sífilis/epidemiología , Sífilis/microbiología , Macrólidos/farmacología , Macrólidos/uso terapéutico , Linezolid/farmacología , Linezolid/uso terapéutico , Ceftriaxona/farmacología , Ceftriaxona/uso terapéutico , Globo Pálido , Farmacorresistencia Bacteriana/genética , Amoxicilina/farmacología , Amoxicilina/uso terapéutico , Treponema
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