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1.
Can Vet J ; 65(6): 569-573, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38827591

RESUMEN

Objective: The present study was designed to identify tick species and determine prevalence of Borrelia burgdorferi infection in ticks obtained from companion animals in British Columbia. Animals and samples: Ticks were submitted by British Columbia veterinarians from client-owned companion animals over a 31-month period. Procedure: Each tick was identified and PCR testing for B. burgdorferi undertaken on all Ixodes species identified by the Zoonotic Diseases and Emerging Pathogens Section of British Columbia Centre for Disease Control Public Health Laboratory (BCCDC PHL). Results: Overall, 85% (n = 300) of ticks submitted were Ixodes spp., with the majority known to transmit B. burgdorferi. Furthermore, 0.8% (95% confidence interval: 0.094 to 2.78%) of these ticks were PCR-positive for B. burgdorferi. Conclusion and clinical relevance: Although the B. burgdorferi positivity rate in this study was low, it remains important for veterinary professionals to inform pet owners that ticks are present and can pose a risk to pets and humans. In eastern North America, B. burgdorferi infection risk has increased rapidly, underscoring the importance of ongoing surveillance in British Columbia to understand current and future distributions of ticks and tick-borne pathogens, especially in the context of climate change.


Surveillance passive des tiques et détection de Borrelia burgdorferi chez des tiques provenant d'animaux de compagnie en Colombie-Britannique: 2018 à 2020. Objectif: Cette étude a été élaboré afin d'identifier les espèces de tiques et de déterminer la prévalence de l'infection à Borrelia burgdorferi chez des tiques obtenues d'animaux de compagnie en Colombie-Britannique. Animaux et échantillons: Les tiques ont été soumises par des médecins vétérinaires de la Colombie-Britannique obtenues d'animaux de compagnie de clients sur une période de 31 mois. Procédure: Chaque tique a été identifiée et un test PCR pour détecter B. burdorferi réalisé sur toutes les espèces Ixodes identifiées par la Section des maladies zoonotiques et des agents pathogènes émergents du Centre for Disease Control Public Health Laboratory de la Colombie-Britannique. Résultats: Au total, 85 % (n = 300) des tiques soumises étaient des Ixodes spp., dont la majorité reconnue pour transmettre B. burgdorferi. De plus, 0,8 % (intervalle de confiance 95 %: 0,094 à 2,78 %) de ces tiques étaient positives pour B. burgdorferi par PCR. Conclusion et signification clinique: Bien que le taux de positivité pour B. burgdorferi dans la présente étude soit faible, il n'en demeure pas moins important pour les professionnels vétérinaires d'informer les propriétaires d'animaux de compagnie que les tiques sont présentes et peuvent représenter un risque pour les animaux de compagnie et les humains. Dans le nord de l'Amérique du Nord, le risque d'infection par B. burgdorferi a augmenté rapidement, soulignant l'importance d'une surveillance continue en Colombie-Britannique pour comprendre la distribution actuelle et future des tiques et agents pathogènes transmis par les tiques, spécialement dans le contexte des changements climatiques.(Traduit par Dr Serge Messier).


Asunto(s)
Borrelia burgdorferi , Ixodes , Enfermedad de Lyme , Mascotas , Animales , Colombia Británica/epidemiología , Borrelia burgdorferi/aislamiento & purificación , Enfermedad de Lyme/veterinaria , Enfermedad de Lyme/epidemiología , Ixodes/microbiología , Perros , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Gatos , Enfermedades de los Gatos/epidemiología , Enfermedades de los Gatos/microbiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/epidemiología , Femenino , Prevalencia , Masculino
2.
Microbiol Resour Announc ; 13(2): e0087923, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38179914

RESUMEN

Whole-genome sequences are presented for three Borrelia burgdorferi, a causative agent of Lyme disease in North America, isolated from Ixodes pacificus ticks collected in British Columbia, Canada. Shotgun DNA libraries were prepared with Illumina DNA Prep and sequenced using the MiniSeq platform. Genome assemblies enabled multilocus sequence typing and ospC typing.

3.
Can Commun Dis Rep ; 49(6): 288-298, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38444700

RESUMEN

Background: Ixodes scapularis and Ixodes pacificus ticks are the principal vectors of the agent of Lyme disease and several other tick-borne diseases in Canada. Tick surveillance data can be used to identify local tick-borne disease risk areas and direct public health interventions. The objective of this article is to describe the seasonal and spatial characteristics of the main Lyme disease vectors in Canada, and the tick-borne pathogens they carry, using passive and active surveillance data from 2020. Methods: Passive and active surveillance data were compiled from the National Microbiology Laboratory Branch (Public Health Agency of Canada), provincial and local public health authorities, and eTick (an online, image-based platform). Seasonal and spatial analyses of ticks and their associated pathogens are presented, including infection prevalence estimates. Results: In passive surveillance, I. scapularis (n=7,534) were submitted from all provinces except Manitoba and British Columbia, while I. pacificus (n=718) were submitted only from British Columbia. No ticks were submitted from the Territories. The seasonal distribution of I. scapularis submissions was bimodal, but unimodal for I. pacificus. Four tick-borne pathogens were identified in I. scapularis (Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti and Borrelia miyamotoi) and one in I. pacificus (B. miyamotoi). In active surveillance, I. scapularis (n=688) were collected in Ontario, Québec and New Brunswick. Five tick-borne pathogens were identified: B. burgdorferi, A. phagocytophilum, B. microti, B. miyamotoi and Powassan virus. Conclusion: This article provides a snapshot of the distribution of I. scapularis and I. pacificus and their associated human pathogens in Canada in 2020, which can help assess the risk of exposure to tick-borne pathogens in different provinces.

4.
Microbiol Spectr ; 10(3): e0068622, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35658597

RESUMEN

British Columbia (BC) implemented the syphilis reverse screening algorithm and Treponema pallidum PCR testing in 2014. We summarize the performance characteristics of the algorithm, together with PCR direct detection, and report on syphilis cases identified from 2015 to 2020. Prior to 2015, samples for syphilis diagnosis were first screened by rapid plasma reagin (RPR). As of 2015, sera were screened by the Siemens Advia Centaur syphilis assay (enzyme immunoassay [EIA]). Positive and equivocal samples were reflex tested by a T. pallidum passive particle agglutination assay (TPPA) and RPR. We used T. pallidum DNA PCR on clinical samples and restriction fragment length polymorphism analysis to identify azithromycin resistance mutations. Case/epidemiological data were obtained from the BC surveillance system. Of 1,631,519 samples screened by the EIA, 72,492 (4.4%) were positive and 187 (<0.1%) were equivocal. Of EIA-positive/equivocal samples, 10.6% were false positive, and false positivity was higher at lower EIA indices. The reverse algorithm detected 4,693 late latent syphilis cases that likely would have been missed by RPR screening. PCR had a very high sensitivity of 100% versus 52.9% and 52.4% for dark-field (DF) and immunofluorescence (IF) microscopy, respectively. The azithromycin resistance mutation A2058G was identified in 96% of PCR-positive samples, and A2059G was identified in 4%. Annually, there were 944 to 1,467 syphilis cases, with 62% in men who reported male sexual partners. The reverse algorithm had a low false-positive rate and very few equivocal screening results but did identify previously undiagnosed late latent syphilis cases. PCR was more sensitive than both DF and IF microscopy for direct diagnosis and enabled monitoring for azithromycin resistance. IMPORTANCE In this study, we summarize the performance characteristics of the algorithm, together with PCR direct detection and epidemiological analysis, and report on syphilis cases identified from 2015 to 2020. This allowed us to paint a complete picture of the outcome of the utilization of the reverse algorithm for diagnosing syphilis cases. The study clearly showed that the reverse algorithm had a low false-positive rate and very few equivocal screening results but did identify previously undiagnosed late latent syphilis cases. PCR was more sensitive than both DF and IF microscopy for direct diagnosis and enabled monitoring for azithromycin resistance.


Asunto(s)
Sífilis , Treponema pallidum , Algoritmos , Azitromicina , Colombia Británica , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Sífilis/diagnóstico , Sífilis/epidemiología , Treponema pallidum/genética
5.
Can Commun Dis Rep ; 48(5): 208-218, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37325256

RESUMEN

Background: The primary vectors of the agent of Lyme disease in Canada are Ixodes scapularis and Ixodes pacificus ticks. Surveillance for ticks and the pathogens they can transmit can inform local tick-borne disease risk and guide public health interventions. The objective of this article is to characterize passive and active surveillance of the main Lyme disease tick vectors in Canada in 2019 and the tick-borne pathogens they carry. Methods: Passive surveillance data were compiled from the National Microbiology Laboratory Branch and provincial public health data sources. Active surveillance was conducted in selected sentinel sites in all provinces. Descriptive analysis of ticks submitted and infection prevalence of tick-borne pathogens are presented. Seasonal and spatial trends are also described. Results: In passive surveillance, specimens of I. scapularis (n=9,858) were submitted from all provinces except British Columbia and I. pacificus (n=691) were submitted in British Columbia and Alberta. No ticks were submitted from the territories. The seasonal distribution pattern was bimodal for I. scapularis adults, but unimodal for I. pacificus adults. Borrelia burgdorferi was the most prevalent pathogen in I. scapularis (18.8%) and I. pacificus (0.3%). In active surveillance, B. burgdorferi was identified in 26.2% of I. scapularis; Anaplasma phagocytophilum in 3.4% of I. scapularis, and Borrelia miyamotoi and Powassan virus in 0.5% or fewer of I. scapularis. These same tick-borne pathogens were not found in the small number of I. pacificus tested. Conclusion: This surveillance article provides a snapshot of the main Lyme disease vectors in Canada and their associated pathogens, which can be used to monitor emerging risk areas for exposure to tick-borne pathogens.

6.
Access Microbiol ; 3(8): 000257, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34888485

RESUMEN

We compared neutralization assays using either the wild-type severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus or surrogate neutralization markers, using characterized sera. We found the results of the neutralization assays 75 % concordant overall and 80 % concordant for samples with high antibody levels. This demonstrates that commercial surrogate SARS-CoV-2 assays offer the potential to assess anti-SARS-CoV-2 antibodies' neutralizing capacity outside CL-3 laboratory containment.

7.
Nat Microbiol ; 6(12): 1549-1560, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34819643

RESUMEN

Syphilis, which is caused by the sexually transmitted bacterium Treponema pallidum subsp. pallidum, has an estimated 6.3 million cases worldwide per annum. In the past ten years, the incidence of syphilis has increased by more than 150% in some high-income countries, but the evolution and epidemiology of the epidemic are poorly understood. To characterize the global population structure of T. pallidum, we assembled a geographically and temporally diverse collection of 726 genomes from 626 clinical and 100 laboratory samples collected in 23 countries. We applied phylogenetic analyses and clustering, and found that the global syphilis population comprises just two deeply branching lineages, Nichols and SS14. Both lineages are currently circulating in 12 of the 23 countries sampled. We subdivided T. p. pallidum into 17 distinct sublineages to provide further phylodynamic resolution. Importantly, two Nichols sublineages have expanded clonally across 9 countries contemporaneously with SS14. Moreover, pairwise genome analyses revealed examples of isolates collected within the last 20 years from 14 different countries that had genetically identical core genomes, which might indicate frequent exchange through international transmission. It is striking that most samples collected before 1983 are phylogenetically distinct from more recently isolated sublineages. Using Bayesian temporal analysis, we detected a population bottleneck occurring during the late 1990s, followed by rapid population expansion in the 2000s that was driven by the dominant T. pallidum sublineages circulating today. This expansion may be linked to changing epidemiology, immune evasion or fitness under antimicrobial selection pressure, since many of the contemporary syphilis lineages we have characterized are resistant to macrolides.


Asunto(s)
Filogenia , Sífilis/microbiología , Treponema pallidum/aislamiento & purificación , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Genoma Bacteriano , Humanos , Macrólidos/farmacología , Treponema pallidum/clasificación , Treponema pallidum/genética , Treponema pallidum/fisiología
8.
Vector Borne Zoonotic Dis ; 21(7): 490-497, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33826423

RESUMEN

Lyme disease, caused by Borrelia burgdorferi sensu lato (s.l.) complex, is the most common vector-borne disease in North America. This disease has a much lower incidence in western compared with eastern North America. Passive tick surveillance data submitted over 17 years from 2002 to 2018 were analyzed to determine the occurrence of tick species and the prevalence of Borrelia spp. in ticks in British Columbia (BC), Canada. The BC Centre for Disease Control Public Health Laboratory received tick submissions from physicians, veterinarians, and BC residents. Ticks were identified to species, and all ticks, except Dermacentor andersoni, were tested using generic B. burgdorferi s.l. primer sets and species-specific PCR primer sets for B. burgdorferi sensu stricto (s.s.). Tick submission data were analyzed to assess temporal and geographical trends, tick life stages, and tick species. Poisson regression was used to assess temporal trends in annual tick submissions. A total of 15,464 ticks were submitted. Among these, 0.29% (n = 10,235) of Ixodes spp. ticks and 5.3% (n = 434) of Rhipicephalus sanguineus ticks were found carrying B. burgdorferi s.s. B. burgdorferi s.s. was primarily detected in Ixodes pacificus (52%; n = 16) and Ixodes angustus ticks (19%; n = 6) retrieved from humans (n = 5) and animals (n = 26). B. burgdorferi was found in ticks submitted throughout the year. Ixodes spp. ticks were primarily submitted from the coastal regions of southwestern BC, and D. andersoni ticks were primarily submitted from southern interior BC. The number of human tick submissions increased significantly (p < 0.001) between 2013 and 2018. The annual prevalence of B. burgdorferi in ticks remained stable during the study period. These findings correspond to those observed in US Pacific Northwestern states. Passive tick surveillance is an efficient tool to monitor long-term trends in tick distribution and B. burgdorferi prevalence in a low endemicity region.


Asunto(s)
Borrelia burgdorferi , Borrelia , Ixodes , Enfermedad de Lyme , Animales , Borrelia/genética , Borrelia burgdorferi/genética , Colombia Británica/epidemiología , Enfermedad de Lyme/epidemiología , Enfermedad de Lyme/veterinaria
9.
Open Forum Infect Dis ; 8(3): ofab043, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33723509

RESUMEN

A comparison of rapid point-of-care serology tests using finger prick and venous blood was done on 278 participants. In a laboratory setting, immunoglobulin G (IgG) sensitivity neared 100%; however, IgG sensitivity dramatically dropped (82%) in field testing. Possible factors include finger prick volume variability, hemolysis, cassette readability, and operator training.

10.
Emerg Infect Dis ; 26(4): 648-657, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32187009

RESUMEN

Tickborne diseases are rare in Washington, USA, and the ecology of these pathogens is poorly understood. We integrated surveillance data from humans and ticks to better describe their epidemiology and ecology. During 2011-2016, a total of 202 tickborne disease cases were reported in Washington residents. Of these, 68 (34%) were autochthonous, including cases of Lyme disease, Rocky Mountain spotted fever, tickborne relapsing fever, and tularemia. During May 2011-December 2016, we collected 977 host-seeking ticks, including Ixodes pacificus, I. angustus, I. spinipalpis, I. auritulus, Dermacentor andersoni, and D. variabilis ticks. The prevalence of Borrelia burgdorferi sensu stricto in I. pacificus ticks was 4.0%; of B. burgdorferi sensu lato, 3.8%; of B. miyamotoi, 4.4%; and of Anaplasma phagocytophilum, 1.9%. We did not detect Rickettsia rickettsii in either Dermacentor species. Case-patient histories and detection of pathogens in field-collected ticks indicate that several tickborne pathogens are endemic to Washington.


Asunto(s)
Anaplasma phagocytophilum , Borrelia burgdorferi , Ixodes , Enfermedad de Lyme , Anaplasma phagocytophilum/genética , Animales , Humanos , Washingtón/epidemiología
11.
Ticks Tick Borne Dis ; 11(1): 101277, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31501035

RESUMEN

'Candidatus Ehrlichia khabarensis' was first described from rodents and insectivores in the Far East territory of Khabarovsk on the Russian Pacific Coast. Here we report the detection of DNA from this microorganism in rodents and fed ticks collected from rodents in British Columbia, Canada in 2013-2014. 'Candidatus Ehrlichia khabarensis' was detected in (i) a female Ixodes angustus tick collected from a Peromyscus maniculatus; (ii) a female Dermacentor andersoni tick collected from a Perognathus parvus; (iii) a pool of 2 larval Ixodes pacificus ticks collected from a single P. maniculatus; and (iv) a pool of 3 nymphal I. pacificus ticks collected from a single P. maniculatus. Three of these four rodents (2 P. maniculatus and 1 P. parvus) with infected ticks also had evidence of 'Candidatus Ehrlichia khabarensis' in at least one tissue type. The infected P. maniculatus and Ixodes ticks came from the Vancouver area in western British Columbia and the P. parvus and Dermacentor tick from an inland site in central British Columbia. Although it remains to be determined whether 'Candidatus Ehrlichia khabarensis' has any negative impacts on wildlife, domestic animals or humans, we note that all three tick species found to contain the DNA of this microorganism are known to bite humans. Future detection of this microorganism either in ticks collected from rodents and allowed to molt to the next life stage prior to being tested, or from host-seeking ticks, is required to determine if it can survive the tick's molt after being ingested via an infectious blood meal.


Asunto(s)
Dermacentor/microbiología , Ehrlichia/aislamiento & purificación , Ixodes/microbiología , Roedores/microbiología , Animales , Colombia Británica , Dermacentor/crecimiento & desarrollo , Femenino , Ixodes/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/microbiología , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Peromyscus/microbiología , Peromyscus/parasitología , Roedores/parasitología
12.
Sex Transm Dis ; 46(4): e42-e45, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30365462

RESUMEN

A guanine mononucleotide repeat in the rpsA (tp0279) gene was evaluated for improved strain discrimination using 72 Treponema pallidum-positive specimens. The tandem repeat combined with the enhanced Centers for Disease Control and Prevention typing system resulted in increased discrimination and should be useful for molecular epidemiologic studies on syphilis especially in outbreaks and among men who have sex with men.


Asunto(s)
ADN Bacteriano/genética , Tipificación Molecular/métodos , Sífilis/microbiología , Secuencias Repetidas en Tándem , Treponema pallidum/clasificación , Genotipo , Homosexualidad Masculina , Humanos , Masculino , Mutación Puntual , ARN Ribosómico 23S/genética
13.
Vector Borne Zoonotic Dis ; 17(12): 821-824, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29083955

RESUMEN

BACKGROUND: Tick paralysis is a frequently overlooked severe disease characterized by bilateral ascending flaccid paralysis caused by a neurotoxin produced by feeding ticks. We aimed to characterize suspected tick paralysis cases documented at the BC Centre for Disease Control (BCCDC) in British Columbia (BC) from 1993 to 2016 and reviewed prevention, diagnosis, and treatment considerations. METHODS: Demographic, geographic, and clinical data from test requisition forms for ticks submitted to the BCCDC Public Health Laboratory (PHL) from patients across BC between 1993 and 2016 for suspected human and animal tick paralysis were reviewed. Descriptive statistics were generated to characterize tick paralysis cases in BC, including tick species implicated, seasonality of disease, and regional differences. RESULTS: From 1993 to 2016, there were 56 cases of suspected tick paralysis with at least one tick specimen submitted for testing at the BCCDC PHL. Humans and animals were involved in 43% and 57% of cases, respectively. The majority of cases involved a Dermacentor andersoni tick (48 cases or 86%) and occurred between the months of April and June (49 cases or 88%). Among known locations of tick acquisition, the Interior region of BC was disproportionately affected, with 25 cases (69%) of tick bites occurring in that area. CONCLUSIONS: Tick paralysis is a rare condition in BC. The region of highest risk is the Interior, particularly during the spring and summer months. Increasing awareness of tick paralysis among healthcare workers and the general public is paramount to preventing morbidity and mortality from this rare disease.


Asunto(s)
Enfermedades de los Perros/etiología , Ixodidae , Mordeduras de Garrapatas/veterinaria , Parálisis por Garrapatas/veterinaria , Adulto , Animales , Colombia Británica/epidemiología , Camélidos del Nuevo Mundo , Niño , Estudios de Cohortes , Enfermedades de los Perros/epidemiología , Perros , Humanos , Masculino , Estudios Retrospectivos , Estaciones del Año , Mordeduras de Garrapatas/complicaciones , Parálisis por Garrapatas/epidemiología
14.
Vector Borne Zoonotic Dis ; 15(11): 701-5, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26502354

RESUMEN

To determine the prevalence of Borrelia burgdorferi in British Columbian ticks, fieldwork was conducted over a 2-year period. In all, 893 ticks (Ixodes pacificus, I. angustus, I. soricis, Ixodes spp., and Dermacentor andersoni) of different life stages were retrieved from 483 small rodents (Peromyscus maniculatus, Perognathus parvus, and Reithrodontomys megalotis). B. burgdorferi DNA was detected in 5 out of 359 tick pools, and 41 out of 483 mice were serologically confirmed to have antibodies against B. burgdorferi. These results were consistent with previous studies, data from passive surveillance in British Columbia, and data from neighboring states in the Pacific Northwest, suggesting a continually low prevalence of B. burgdorferi in British Columbia ticks.


Asunto(s)
Borrelia burgdorferi/aislamiento & purificación , Dermacentor/microbiología , Ixodes/microbiología , Roedores/microbiología , Animales , Vectores Arácnidos/microbiología , Borrelia burgdorferi/genética , Borrelia burgdorferi/inmunología , Colombia Británica/epidemiología , ADN Bacteriano/sangre , Prevalencia , Roedores/parasitología , Análisis de Secuencia de ADN , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/virología
15.
Mycopathologia ; 173(5-6): 311-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21960040

RESUMEN

It has been over a decade since Cryptococcus gattii was first recognized as the causative organism of an outbreak of cryptococcosis on Vancouver Island, British Columbia. A number of novel observations have been associated with the study of this emergent pathogen. A novel genotype of C. gattii, VGIIa was described as the major genotype associated with clinical disease. Minor genotypes, VGIIb and VGI, are also responsible for disease in British Columbians, in both human and animal populations. The clinical major genotype VGIIa and minor genotype VGIIb are identical to C. gattii isolated from the environment of Vancouver Island. There is more heterogeneity in VGI, and a clear association with the environment is not apparent. Between 1999 and 2010, there have been 281 cases of C. gattii cryptococcosis. Risk factors for infection are reported to be age greater than 50 years, history of smoking, corticosteroid use, HIV infection, and history of cancer or chronic lung disease. The major C. gattii genotype VGIIa is as virulent in mice as the model Cryptococcus, H99 C. neoformans, although the outbreak strain produces a less protective inflammatory response in C57BL/6 mice. The minor genotype VGIIb is significantly less virulent in mouse models. Cryptococcus gattii is found associated with native trees and soil on Vancouver Island. Transiently positive isolations have been made from air and water. An ecological niche for this organism is associated within a limited biogeoclimatic zone characterized by daily average winter temperatures above freezing.


Asunto(s)
Criptococosis/epidemiología , Criptococosis/microbiología , Cryptococcus gattii/aislamiento & purificación , Brotes de Enfermedades , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Colombia Británica/epidemiología , Niño , Preescolar , Criptococosis/inmunología , Cryptococcus gattii/clasificación , Cryptococcus gattii/genética , Modelos Animales de Enfermedad , Femenino , Genotipo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Epidemiología Molecular , Factores de Riesgo , Adulto Joven
16.
J Vector Ecol ; 35(1): 124-39, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20618658

RESUMEN

Lyme disease is reported across Canada, but pinpointing the source of infection has been problematic. In this three-year, bird-tick-pathogen study (2004-2006), 366 ticks representing 12 species were collected from 151 songbirds (31 passerine species/subspecies) at 16 locations Canada-wide. Of the 167 ticks/pools tested, 19 (11.4%) were infected with Borrelia burgdorferi sensu lato (s.l.). Sequencing of the rrf-rrl intergenic spacer gene revealed four Borrelia genotypes: B. burgdorferi sensu stricto (s.s.) and three novel genotypes (BC genotype 1, BC genotype 2, BC genotype 3). All four genotypes were detected in spirochete-infected Ixodes auritulus (females, nymphs, larvae) suggesting this tick species is a vector for B. burgdorferi s.l. We provide first-time records for: ticks in the Yukon (north of 60 degrees latitude), northernmost collection of Amblyomma americanum in North America, and Amblyomma imitator in Canada. First reports of bird-derived ticks infected with B. burgdorferi s.l. include: live culture of spirochetes from Ixodes pacificus (nymph) plus detection in I. auritulus nymphs, Ixodes scapularis in New Brunswick, and an I. scapularis larva in Canada. We provide the first account of B. burgdorferi s. l. in an Ixodes muris tick collected from a songbird anywhere. Congruent with previous data for the American Robin, we suggest that the Common Yellowthroat, Golden-crowned Sparrow, Song Sparrow, and Swainson's Thrush are reservoir-competent hosts. Song Sparrows, the predominant hosts, were parasitized by I. auritulus harboring all four Borrelia genotypes. Our results show that songbirds import B. burgdorferi s.l.-infected ticks into Canada. Bird-feeding I. scapularis subadults were infected with Lyme spirochetes during both spring and fall migration in eastern Canada. Because songbirds disperse millions of infected ticks across Canada, people and domestic animals contract Lyme disease outside of the known and expected range.


Asunto(s)
Borrelia burgdorferi/crecimiento & desarrollo , Enfermedad de Lyme/microbiología , Garrapatas/microbiología , Animales , Borrelia burgdorferi/clasificación , Borrelia burgdorferi/genética , Canadá , Genotipo , Enfermedad de Lyme/transmisión , Pájaros Cantores/parasitología , Garrapatas/crecimiento & desarrollo
17.
J Vector Ecol ; 33(1): 64-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18697308

RESUMEN

Borrelia burgdorferi sensu stricto (s.s.) was isolated from questing adult Ixodes scapularis Say ticks collected from Turkey Point Provincial Park (TPPP), Ontario, Canada during 2005-2006. DNA from ten (67%) of 15 pools of ticks was confirmed positive for B. burgdorferi s.s. using polymerase chain reaction (PCR) by targeting the rrf (5S)-rrl (23S) intergenic spacer region and OspA genes. This significant infection rate indicates an accelerated development of B. burgdorferi s.s. in TPPP, because this pathogen was not detected five years previously during sampling of the three motile life stages of I. scapularis. Our study provides the initial report of the presence of B. burgdorferi s.s. in TPPP, which is now endemic for Lyme disease. Ultimately, people and domestic animals are at risk of contracting Lyme disease when they frequent this park.


Asunto(s)
Borrelia burgdorferi/crecimiento & desarrollo , Insectos Vectores/microbiología , Ixodes/microbiología , Enfermedad de Lyme/microbiología , Animales , Antígenos de Superficie/genética , Proteínas de la Membrana Bacteriana Externa/genética , Vacunas Bacterianas/genética , Secuencia de Bases , Borrelia burgdorferi/clasificación , Borrelia burgdorferi/genética , ADN Intergénico/genética , Femenino , Humanos , Lipoproteínas/genética , Enfermedad de Lyme/transmisión , Masculino , Datos de Secuencia Molecular , Ontario , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico
18.
Int J STD AIDS ; 19(8): 568-9, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18663050

RESUMEN

The brain gumma is a rare manifestation of the tertiary stage of syphilis. A case of neurosyphilitic gumma was confirmed by the Treponema pallidum polymerase chain reaction in a 46-year-old HIV-positive homosexual man. The patient presented with a severe headache and was hospitalized. A computed tomography scan was performed which revealed a left frontal lobe mass. Lymphoma was suspected. However, infectious disease diagnostics were performed on the cerebrospinal fluid that included investigations for syphilis and other microbiological agents such as Toxoplasma gondii. This revealed a reactive venereal disease research laboratory test, a reactive syphilis rapid plasma reagin and a reactive T. pallidum particle agglutination test. The patient was treated for syphilis till complete recovery.


Asunto(s)
Encéfalo/microbiología , Infecciones por VIH/complicaciones , Homosexualidad Masculina , Neurosífilis/diagnóstico , Reacción en Cadena de la Polimerasa , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación , Encéfalo/diagnóstico por imagen , Líquido Cefalorraquídeo/microbiología , VIH-1 , Humanos , Masculino , Persona de Mediana Edad , Neurosífilis/diagnóstico por imagen , Neurosífilis/microbiología , Reacción en Cadena de la Polimerasa/métodos , Tomografía Computarizada por Rayos X
19.
FEMS Immunol Med Microbiol ; 49(2): 184-91, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17328752

RESUMEN

The role of molecular detection, identification and typing or fingerprinting of microorganisms has shifted gradually from the academic world to the routine diagnostic laboratory. Molecular methods have been used increasingly over the past decade to improve the sensitivity, specificity and turn-around time in the clinical laboratory. Molecular methods have also been used to identify new and nonculturable agents. Many high-throughput molecular tests are now available commercially, which impacts on the infrastructure in many of the diagnostic laboratories. In this paper, we take an overall look at the use of molecular methods (prospects vs. pitfalls) based on our clinical and public health experience, particularly as they related to Borrelia burgdorferi, a vector-borne pathogen, Treponema pallidum, a re-emerging sexually transmitted global pathogen, and West Nile virus, a newly recognized virus in North America.


Asunto(s)
Técnicas de Laboratorio Clínico/tendencias , Infecciones/diagnóstico , Técnicas de Diagnóstico Molecular/tendencias , Humanos , Enfermedad de Lyme/diagnóstico , Sífilis/diagnóstico , Fiebre del Nilo Occidental/diagnóstico
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