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1.
Sci Rep ; 11(1): 16584, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34400676

RESUMEN

Currently, there are increasing concerns about the possibility of a new epidemic due to emerging reports of Mayaro virus (MAYV) fever outbreaks in areas of South and Central America. Haemagogus mosquitoes, the primary sylvan vectors of MAYV are poorly characterized and a better understanding of the mosquito's viral transmission dynamics and interactions with MAYV and other microorganisms would be important in devising effective control strategies. In this study, a metatranscriptomic based approach was utilized to determine the prevalence of RNA viruses in field-caught mosquitoes morphologically identified as Haemagogus janthinomys from twelve (12) forest locations in Trinidad, West Indies. Known insect specific viruses including the Phasi Charoen-like and Humaiata-Tubiacanga virus dominated the virome of the mosquitoes throughout sampling locations while other viruses such as the avian leukosis virus, MAYV and several unclassified viruses had a narrower distribution. Additionally, assembled contigs from the Ecclesville location suggests the presence of a unique uncharacterized picorna-like virus. Mapping of RNA sequencing reads to reference mitochondrial sequences of potential feeding host animals showed hits against avian and rodent sequences, which putatively adds to the growing body of evidence of a potentially wide feeding host-range for the Haemagogus mosquito vector.

2.
Virology ; 562: 50-62, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34256244

RESUMEN

We describe the isolation and characterization of a novel insect-specific flavivirus (ISFV), tentatively named Aripo virus (ARPV), that was isolated from Psorophora albipes mosquitoes collected in Trinidad. The ARPV genome was determined and phylogenetic analyses showed that it is a dual host associated ISFV, and clusters with the main mosquito-borne flaviviruses. ARPV antigen was significantly cross-reactive with Japanese encephalitis virus serogroup antisera, with significant cross-reactivity to Ilheus and West Nile virus (WNV). Results suggest that ARPV replication is limited to mosquitoes, as it did not replicate in the sandfly, culicoides or vertebrate cell lines tested. We also demonstrated that ARPV is endocytosed into vertebrate cells and is highly immunomodulatory, producing a robust innate immune response despite its inability to replicate in vertebrate systems. We show that prior infection or coinfection with ARPV limits WNV-induced disease in mouse models, likely the result of a robust ARPV-induced type I interferon response.

3.
Ticks Tick Borne Dis ; 12(4): 101730, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33957484

RESUMEN

Hunters are at a higher risk for exposure to zoonotic pathogens due to their close interactions with wildlife and arthropod vectors. In this study, high throughput sequencing was used to explore the viromes of two tick species, Amblyomma dissimile and Haemaphysalis juxtakochi, removed from hunted wildlife in Trinidad and Tobago. We identified sequences from 3 new viral species, from the viral families Orthomyxoviridae, Chuviridae and Tetraviridae in A. dissimile.


Asunto(s)
Ciervos , Iguanas , Ixodidae/virología , Infecciones por Orthomyxoviridae/veterinaria , Orthomyxoviridae/aislamiento & purificación , Animales , Orthomyxoviridae/clasificación , Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/virología , Filogenia , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/veterinaria , Trinidad y Tobago , Proteínas Virales/análisis
4.
Nat Biotechnol ; 39(8): 989-999, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33859400

RESUMEN

Plasma-derived polyclonal antibody therapeutics, such as intravenous immunoglobulin, have multiple drawbacks, including low potency, impurities, insufficient supply and batch-to-batch variation. Here we describe a microfluidics and molecular genomics strategy for capturing diverse mammalian antibody repertoires to create recombinant multivalent hyperimmune globulins. Our method generates of diverse mixtures of thousands of recombinant antibodies, enriched for specificity and activity against therapeutic targets. Each hyperimmune globulin product comprised thousands to tens of thousands of antibodies derived from convalescent or vaccinated human donors or from immunized mice. Using this approach, we generated hyperimmune globulins with potent neutralizing activity against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in under 3 months, Fc-engineered hyperimmune globulins specific for Zika virus that lacked antibody-dependent enhancement of disease, and hyperimmune globulins specific for lung pathogens present in patients with primary immune deficiency. To address the limitations of rabbit-derived anti-thymocyte globulin, we generated a recombinant human version and demonstrated its efficacy in mice against graft-versus-host disease.


Asunto(s)
Linfocitos B/inmunología , COVID-19/terapia , Globulinas/biosíntesis , SARS-CoV-2/inmunología , Animales , Anticuerpos Antivirales/inmunología , Células CHO , Cricetulus , Ensayo de Inmunoadsorción Enzimática , Globulinas/inmunología , Humanos , Inmunización Pasiva , Ratones , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Virus Zika/inmunología
5.
Transbound Emerg Dis ; 67(6): 2775-2788, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32438523

RESUMEN

Avian coronaviruses, including infectious bronchitis virus (IBV) and turkey coronavirus (TCoV), are economically important viruses affecting poultry worldwide. IBV is responsible for causing severe losses to the commercial poultry sector globally. The objectives of this study were to identify the viruses that were causing outbreaks of severe respiratory disease in chickens in Trinidad and Tobago (T&T) and to characterize the strains. Swab samples were collected from birds showing severe respiratory signs in five farms on the island of Trinidad. Samples were tested for the presence of IBV, as well as avian influenza virus (AIV), Newcastle disease virus (NDV) and avian metapneumovirus (aMPV) by real-time reverse transcription polymerase chain reaction (qRT-PCR). All samples from the five farms tested negative for AIV, NDV and aMPV; however, samples from clinically affected birds in all five of the farms tested positive for IBV. Genetic data revealed the presence of TCoV in chickens on two of the farms. Interestingly, these two farms had never reared turkeys. Phylogenetic analysis showed that IBV S1 sequences formed two distinct clusters. Two sequences grouped with vaccine strains within the GI-1 lineage, whereas three sequences grouped together, but separately from other defined lineages, forming a likely new lineage of IBV. Pairwise comparison revealed that the three unique variant strains within the distinct lineage of IBV were significantly different in their S1 nucleotide coding regions from viruses in the closest lineage (16% difference) and locally used vaccine strains (>20% difference). Results also suggested that one of the samples was a recombinant virus, generated from a recombination event between a Trinidad virus of the GI-1 lineage and a Trinidad virus of the newly defined lineage. Many amino acid differences were also observed between the S1 coding regions of the circulating field and vaccine strains, indicating that the IBV vaccines may not be protective. Vaccine-challenge studies are however needed to prove this.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Enfermedades de las Aves de Corral/virología , Infecciones del Sistema Respiratorio/veterinaria , Vacunas Virales/inmunología , Animales , Pollos , Infecciones por Coronavirus/virología , Patos , Gansos , Virus de la Bronquitis Infecciosa/clasificación , Filogenia , Codorniz , ARN Viral , Infecciones del Sistema Respiratorio/virología , Análisis de Secuencia de ARN/veterinaria , Trinidad y Tobago , Pavos , Vacunación/veterinaria
6.
J Infect Dis ; 221(Suppl 4): S375-S382, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32034942

RESUMEN

Bat-borne zoonotic pathogens belonging to the family Paramxyoviridae, including Nipah and Hendra viruses, and the family Filoviridae, including Ebola and Marburg viruses, can cause severe disease and high mortality rates on spillover into human populations. Surveillance efforts for henipaviruses and filoviruses have been largely restricted to the Old World; however, recent studies suggest a potentially broader distribution for henipaviruses and filoviruses than previously recognized. In the current study, we screened for henipaviruses and filoviruses in New World bats collected across 4 locations in Trinidad near the coast of Venezuela. Bat tissue samples were screened using previously established reverse-transcription polymerase chain reaction assays. Serum were screened using a multiplex immunoassay to detect antibodies reactive with the envelope glycoprotein of viruses in the genus Henipavirus and the family Filoviridae. Serum samples were also screened by means of enzyme-linked immunosorbent assay for antibodies reactive with Nipah G and F glycoproteins. Of 84 serum samples, 28 were reactive with ≥1 henipavirus glycoprotein by ≥1 serological method, and 6 serum samples were reactive against ≥1 filovirus glycoproteins. These data provide evidence of potential circulation of viruses related to the henipaviruses and filoviruses in New World bats.


Asunto(s)
Quirópteros/virología , Infecciones por Filoviridae/veterinaria , Filoviridae , Infecciones por Henipavirus/veterinaria , Henipavirus , Animales , Quirópteros/sangre , Quirópteros/clasificación , Infecciones por Filoviridae/epidemiología , Infecciones por Filoviridae/virología , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/virología , Pruebas Serológicas , Trinidad y Tobago/epidemiología
7.
Viruses ; 12(2)2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32033370

RESUMEN

: Rabies virus (RABV) is the only lyssavirus known to be present within the Caribbean. The island of Trinidad, is richly diverse in chiropteran fauna and endemic for bat-transmitted rabies with low RABV isolation rates observed in this population. We aimed to determine the seroprevalence of rabies virus neutralizing antibodies (RVNA) in light of spatio-temporal and bat demographic factors to infer the extent of natural exposure to RABV in the Trinidadian bat population. RVNA titers were determined by the RABV micro-neutralization test on 383 bat samples representing 21 species, comprising 30.9% of local bat diversity, from 31 locations across the island over 5 years. RVNA was positively detected in 33 samples (8.6%) representing 6 bat species (mainly frugivorous) with titers ranging from 0.1 to 19 IU/mL (mean 1.66 IU/mL). The analyses based on a multivariable binomial generalised linear mixed-effects model showed that bat age and year of capture were significant predictors of seropositivity. Thus, juvenile bats were more likely to be seropositive when compared to adults (estimate 1.13; p = 0.04) which may suggest early exposure to the RABV with possible implications for viral amplification in this population. Temporal variation in rabies seropositivity, 2012-2014 versus 2015-2017 (estimate 1.07; p = 0.03) may have been related to the prevailing rabies epizootic situation. Regarding other factors investigated, RVNA was found in bats from both rural and non-rural areas, as well as in both hematophagous and non-hematophagous bat species. The most common seropositive species, Artibeus jamaicensis planirostris is ubiquitous throughout the island which may potentially facilitate human exposure. The findings of this study should be factored into public health assessments on the potential for rabies transmission by non-hematophagous bats in Trinidad.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Quirópteros/inmunología , Rabia/inmunología , Rabia/veterinaria , Animales , Quirópteros/virología , Femenino , Masculino , Rabia/epidemiología , Virus de la Rabia/inmunología , Estudios Seroepidemiológicos , Trinidad y Tobago/epidemiología
8.
J Zoo Wildl Med ; 50(1): 231-237, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31120683

RESUMEN

Oryzoborus angolensis (Lesser Seed-Finch), Oryzoborus crassirostris (Large-billed Seed-Finch), and Sporophila intermedia (Grey Seedeater) are finch species native to the Caribbean island of Trinidad. These species are locally trapped and kept for their song, but with declining native populations, enthusiasts have turned to illegally importing birds from the South American mainland. The smuggling of wild birds from South America poses significant disease risks to the native bird species of Trinidad. Herein we describe the first case of poxviral infection in these illegally imported birds in Trinidad and partial genome sequence of the causative agent. Phylogenetic analysis of the 4b core protein sequence indicated that the avian poxvirus identified was most closely related to a 2012 avian pox sequence from Brazil, with 96.2% and 98.1% identity at the nucleotide and amino acid level.


Asunto(s)
Enfermedades de las Aves/virología , Genoma Viral , Infecciones por Poxviridae/veterinaria , Poxviridae/genética , Poxviridae/aislamiento & purificación , Pájaros Cantores , Distribución Animal , Animales , Comercio , Pinzones , Filogenia , Poxviridae/clasificación , Infecciones por Poxviridae/virología , Análisis de Secuencia de ADN/veterinaria , Trinidad y Tobago
9.
J Oral Microbiol ; 11(1): 1536181, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30598728

RESUMEN

Chewing gum containing xylitol may help prevent caries by reducing levels of mutans streptococci (MS) and lactobacilli in saliva and plaque. Very little is known about other species which are possibly beneficial to oral health. In this study, we employed high-throughput sequencing of the 16S rRNA gene to profile microbial communities of saliva and plaque following short-term consumption of xylitol and sorbitol containing chewing gum. Participants (n = 30) underwent a washout period and were randomly assigned to one of two groups. Each group chewed either xylitol or sorbitol gum for three weeks, before undergoing a second four-week washout period after which they switched to the alternate gum for three weeks. Analysis of samples collected before and after each intervention identified distinct plaque and saliva microbial communities that altered dependent on the order in which gum treatments were given. Neither the xylitol nor sorbitol treatments significantly affected the bacterial composition of plaque. Lactobacilli were undetected and the number of Streptococcus mutans sequence reads was very low and unaffected by either xylitol or sorbitol. However, sorbitol affected several other streptococcal species in saliva including increasing the abundance of S. cristatus, an oral commensal shown to inhibit bacteria associated with chronic periodontitis.

10.
Vet Microbiol ; 228: 93-100, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30593386

RESUMEN

Vampire bat-transmitted human rabies was first recognized in Trinidad during a major outbreak during the first half of the 20th century. To date, Trinidad is the only Caribbean island with vampire bat-transmitted rabies. Herein, we summarized the epidemiological situation of rabies in Trinidad during the period 1971-2015 through the analysis of field and laboratory records. During the study period, 259 domestic and wild animal rabies cases were laboratory confirmed with an annual median of 2 animal rabies cases. Over the 45 years, five significant epizootic events occurred (in 1974, 1997-1998, 2000, 2010 and 2012-2013) over which there was a significant increasing trend for the occurrence of rabies cases. The highest number of cases (87 cases) occurred during the 1997-1998 event, and the rabies positive proportion, was highest (0.7, 95% CI 0.52-0.84) for the year 2000. Rabies risk was highest for cattle (negative binomial parameter estimate 4.84, 95% CI 3.45-6.76), although numerous rabies cases were seen in the caprine population during the study period. In light of this finding, consideration should be given to including the small ruminant population in the national rabies vaccination program. Outbreaks affected mainly the counties of St. Patrick and St. George East, with epidemic progression outwards, and these areas should be prioritized for prevention and control efforts.


Asunto(s)
Quirópteros/virología , Brotes de Enfermedades/veterinaria , Ganado/virología , Virus de la Rabia/fisiología , Rabia/veterinaria , Animales , Animales Domésticos , Animales Salvajes , Humanos , Rabia/epidemiología , Rabia/prevención & control , Rabia/virología , Trinidad y Tobago/epidemiología , Vacunación/veterinaria , Zoonosis
11.
Sci Rep ; 9(1): 20399, 2019 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-31892710

RESUMEN

Mayaro virus (MAYV) causes an acute febrile illness similar to that produced by chikungunya virus (CHIKV), an evolutionary relative in the Semliki Forest virus complex of alphaviruses. MAYV emergence is typically sporadic, but recent isolations and outbreaks indicate that the virus remains a public health concern. Given the close phylogenetic and antigenic relationship between CHIKV and MAYV, and widespread distribution of CHIKV, we hypothesized that prior CHIKV immunity may affect MAYV pathogenesis and/or influence its emergence potential. We pre-exposed immunocompetent C57BL/6 and immunocompromised A129 or IFNAR mice to wild-type CHIKV, two CHIKV vaccines, or a live-attenuated MAYV vaccine, and challenged with MAYV. We observed strong cross-protection against MAYV for mice pre-exposed to wild-type CHIKV, and moderately but significantly reduced cross-protection from CHIKV-vaccinated animals. Immunity to other alphavirus or flavivirus controls provided no protection against MAYV disease or viremia. Mechanistic studies suggested that neutralizing antibodies alone can mediate this protection, with T-cells having no significant effect on diminishing disease. Finally, human sera obtained from naturally acquired CHIKV infection cross-neutralized MAYV at high titers in vitro. Altogether, our data suggest that CHIKV infection can confer cross-protective effects against MAYV, and the resultant reduction in viremia may limit the emergence potential of MAYV.


Asunto(s)
Infecciones por Alphavirus/inmunología , Infecciones por Alphavirus/transmisión , Anticuerpos Antivirales/inmunología , Fiebre Chikungunya/inmunología , Virus Chikungunya/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Epidemias , Ratones
12.
Trop Med Infect Dis ; 3(3)2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30274485

RESUMEN

Rabies virus is the only Lyssavirus species found in the Americas. In discussions about rabies, Latin America and the Caribbean are often grouped together. Our study aimed to independently analyse the rabies situation in the Caribbean and examine changes in rabies spatiotemporal epidemiology. A questionnaire was administered to the 33 member countries and territories of the Caribbean Animal Health Network (CaribVET) to collect current data, which was collated with a literature review. Rabies was endemic in ten Caribbean localities, with the dog, mongoose, and vampire bat identified as enzootic reservoirs. The majority of animal cases occurred in Puerto Rico, the Dominican Republic, and Haiti, while human cases only consistently occurred in the latter two areas. Rabies vaccination was conducted for high-risk animal populations with variable coverage, and rabies diagnostic capacities varied widely throughout the region. Illegal importation and natural migration of animals may facilitate the introduction of rabies virus variants into virus-naïve areas. Passive surveillance, together with enhanced methods and serological screening techniques, can therefore be of value. The insularity of the Caribbean makes it ideal for conducting pilot studies on reservoir host population management. Best practice guidelines developed for these reservoir hosts can be individually modified to the epidemiological status and available resources within each locality.

13.
Prev Vet Med ; 149: 75-81, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29290303

RESUMEN

Viruses affecting poultry cause significant levels of disease leading to severe economic losses among poultry farmers worldwide. The Americas region continues to be vulnerable to the spread of poultry viruses across the continents and Caribbean island chains. In Trinidad and Tobago (T&T) there is limited information on the viruses circulating in poultry. Many flock are vulnerable to infection and there are occasional outbreaks of disease resulting in high levels of morbidity and mortality. This study aims to identify important viruses of poultry circulating in T&T through a broad-based surveillance approach. Serum samples from 29 layer farms in Trinidad and 14 layer farms in Tobago were collected from the eldest laying hens. Samples were tested from unvaccinated birds for antibodies by enzyme-linked immunosorbent assay (ELISA) against Avian influenza virus (AIV), Infectious bronchitis virus (IBV), Newcastle disease virus (NDV), Infectious laryngotracheitis virus (ILTV), Avian pneumovirus (APV), Infectious bursal disease virus (IBDV), Fowl adenovirus Gp1 (FADV) and Egg drop syndrome virus (EDSV). In Trinidad, the estimated true seroprevalence levels of antibodies were 0% (CI 95%: 0-0%) for AIV, 100% (CI 95%: 97-100%) for IBV, 79.8% (CI 95%: 70.6-86.9%) for NDV, 1% (CI 95%: 0-2.6%) for ILTV, 67.55% (CI 95%: 62.3-72.4%) for APV, 94.93% (CI 95%: 88.0-98.6%) for IBDV, 100% (CI 95%: 99.7-100%) for FADV and 67.8% (CI 95%: 62.4-72.8%) for EDSV. In Tobago, seroprevalence levels were 0% (CI 95%: 0-0%) for AIV, 100% (CI 95%: 95.6-100%) for IBV, 80.5% (CI 95%: 70.1-88.5%) for NDV, 29.9% (CI 95%: 20.8-40.6%) for ILTV, 100% (CI 95%: 97.7-100%) for APV, 97.1% (CI95%: 89.9-100%) for IBDV, 100% (CI 95%: 97.5-100%) for FADV and 100% (CI 95%: 99-100%) for EDSV. The results reveal strong evidence for the circulation of IBV, NDV, APV, IBDV, FADV and EDSV in layer poultry on both islands, as well as ILTV in Tobago.


Asunto(s)
Pollos , Enfermedades de las Aves de Corral/epidemiología , Virosis/veterinaria , Animales , Femenino , Enfermedades de las Aves de Corral/virología , Prevalencia , Estudios Seroepidemiológicos , Trinidad y Tobago/epidemiología , Virosis/epidemiología , Virosis/virología
14.
Trop Anim Health Prod ; 49(6): 1117-1124, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28523387

RESUMEN

The objective of this study was to evaluate the seroprevalence and identify the strains of swine influenza virus (SwIV), as well as the seroprevalence of porcine parvovirus (PPV), transmissible gastroenteritis virus (TGEV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine respiratory coronavirus (PRCV), porcine circovirus type 2 (PCV-2), and classical swine fever virus (CSFV) in pigs in Trinidad and Tobago (T&T). Blood samples (309) were randomly collected from pigs at farms throughout T&T. Serum samples were tested for the presence of antibodies to the aforementioned viruses using commercial ELISA kits, and the circulating strains of SwIV were identified by the hemagglutination inhibition test (HIT). Antibodies against SwIV were detected in 114 out of the 309 samples (37%). Out of a total of 26 farms, 14 tested positive for SwIV antibodies. HI testing revealed high titers against the A/sw/Minnesota/593/99 H3N2 strain and the pH1N1 2009 pandemic strain. Antibodies against PPV were detected in 87 out of the 309 samples (28%), with 11 out of 26 farms testing positive for PPV antibodies. Antibodies against PCV-2 were detected in 205 out of the 309 samples tested (66%), with 25 out of the 26 farms testing positive for PCV-2 antibodies. No antibodies were detected in any of the tested pigs to PRRSV, TGEV, PRCV, or CSFV.


Asunto(s)
Orthomyxoviridae/aislamiento & purificación , Enfermedades de los Porcinos/epidemiología , Virosis/veterinaria , Animales , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/virología , Prevalencia , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/virología , Trinidad y Tobago/epidemiología , Virosis/epidemiología , Virosis/virología
15.
Trop Med Infect Dis ; 2(3)2017 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-30270885

RESUMEN

Vampire bat-transmitted rabies was first recognized in Trinidad during a major outbreak reported in 1925. Trinidad is the only Caribbean island with vampire bat-transmitted rabies. We conducted a literature review to describe the changing epidemiology of rabies in Trinidad and give a historical perspective to rabies prevention and control measures on the island. The last human case of rabies occurred in 1937 and although no case of canine-transmitted rabies was reported since 1914, sporadic outbreaks of bat-transmitted rabies still occur in livestock to date. Over the last century, seven notable epidemics were recorded in Trinidad with the loss of over 3000 animals. During the 1950s, several measures were effectively adopted for the prevention and control of the disease which led to a significant reduction in the number of cases. These measures include: vampire bat population control, livestock vaccination, and animal surveillance. However, due to lapses in these measures over the years (e.g., periods of limited vampire control and incomplete herd vaccination), epidemics have occurred. In light of the significant negative impact of rabies on animal production and human health, rabies surveillance in Trinidad should be enhanced and cases evaluated towards the design and implementation of more evidence-based prevention and control programs.

17.
PLoS Negl Trop Dis ; 9(11): e0004199, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26580074

RESUMEN

Local transmission of Chikungunya virus (CHIKV) was first documented in Trinidad and Tobago (T&T) in July 2014 preceding a large epidemic. At initial presentation, it is difficult to distinguish chikungunya fever (CHIKF) from other acute undifferentiated febrile illnesses (AUFIs), including life-threatening dengue disease. We characterised and compared dengue virus (DENV) and CHIKV infections in 158 patients presenting with suspected dengue fever (DF) and CHIKF at a major hospital in T&T, and performed phylogenetic analyses on CHIKV genomic sequences recovered from 8 individuals. The characteristics of patients with and without PCR-confirmed CHIKV were compared using Pearson's χ2 and student's t-tests, and adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were determined using logistic regression. We then compared signs and symptoms of people with RT-qPCR-confirmed CHIKV and DENV infections using the Mann-Whitney U, Pearson's χ2 and Fisher's exact tests. Among the 158 persons there were 8 (6%) RT-qPCR-confirmed DENV and 30 (22%) RT-qPCR-confirmed CHIKV infections. Phylogenetic analyses showed that the CHIKV strains belonged to the Asian genotype and were most closely related to a British Virgin Islands strain isolated at the beginning of the 2013/14 outbreak in the Americas. Compared to persons who were RT-qPCR-negative for CHIKV, RT-qPCR-positive individuals were significantly more likely to have joint pain (aOR: 4.52 [95% CI: 1.28-16.00]), less likely to be interviewed at a later stage of illness (days post onset of fever--aOR: 0.56 [0.40-0.78]) and had a lower white blood cell count (aOR: 0.83 [0.71-0.96]). Among the 38 patients with RT-qPCR-confirmed CHIKV or DENV, there were no significant differences in symptomatic presentation. However when individuals with serological evidence of recent DENV or CHIKV infection were included in the analyses, there were key differences in clinical presentation between CHIKF and other AUFIs including DF, which can be used to triage patients for appropriate care in the clinical setting.


Asunto(s)
Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/epidemiología , Virus Chikungunya/aislamiento & purificación , Dengue/diagnóstico , Dengue/epidemiología , Técnicas de Diagnóstico Molecular/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fiebre Chikungunya/patología , Virus Chikungunya/clasificación , Virus Chikungunya/genética , Dengue/patología , Diagnóstico Diferencial , Femenino , Fiebre de Origen Desconocido/diagnóstico , Fiebre de Origen Desconocido/epidemiología , Fiebre de Origen Desconocido/patología , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Trinidad y Tobago/epidemiología , Adulto Joven
18.
Diagn Microbiol Infect Dis ; 81(2): 105-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25533614

RESUMEN

Dengue virus (DENV) transmission occurs throughout the Caribbean, though laboratory confirmation and epidemiologic surveillance are limited by the availability of serotype-specific molecular diagnostics. In this study, we show that a serotype-specific DENV multiplex, real-time reverse transcriptase-PCR (RT-PCR) detected DENV RNA in significantly more samples (82/182) than a reference hemi-nested RT-PCR (57/182; P=0.01).


Asunto(s)
Virus del Dengue/clasificación , Virus del Dengue/genética , Dengue/diagnóstico , Dengue/virología , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Serogrupo , Trinidad y Tobago , Adulto Joven
19.
J Virol ; 89(1): 676-87, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25355879

RESUMEN

UNLABELLED: A total of 2,691 mosquitoes representing 17 species was collected from eight locations in southwest Cameroon and screened for pathogenic viruses. Ten isolates of a novel reovirus (genus Dinovernavirus) were detected by culturing mosquito pools on Aedes albopictus (C6/36) cell cultures. A virus that caused overt cytopathic effects was isolated, but it did not infect vertebrate cells or produce detectable disease in infant mice after intracerebral inoculation. The virus, tentatively designated Fako virus (FAKV), represents the first 9-segment, double-stranded RNA (dsRNA) virus to be isolated in nature. FAKV appears to have a broad mosquito host range, and its detection in male specimens suggests mosquito-to-mosquito transmission in nature. The structure of the T=1 FAKV virion, determined to subnanometer resolution by cryoelectron microscopy (cryo-EM), showed only four proteins per icosahedral asymmetric unit: a dimer of the major capsid protein, one turret protein, and one clamp protein. While all other turreted reoviruses of known structures have at least two copies of the clamp protein per asymmetric unit, FAKV's clamp protein bound at only one conformer of the major capsid protein. The FAKV capsid architecture and genome organization represent the most simplified reovirus described to date, and phylogenetic analysis suggests that it arose from a more complex ancestor by serial loss-of-function events. IMPORTANCE: We describe the detection, genetic, phenotypic, and structural characteristics of a novel Dinovernavirus species isolated from mosquitoes collected in Cameroon. The virus, tentatively designated Fako virus (FAKV), is related to both single-shelled and partially double-shelled viruses. The only other described virus in this genus was isolated from cultured mosquito cells. It was previously unclear whether the phenotypic characteristics of that virus were reflective of this genus in nature or were altered during serial passaging in the chronically infected cell line. FAKV is a naturally occurring single-shelled reovirus with a unique virion architecture that lacks several key structural elements thought to stabilize a single-shelled reovirus virion, suggesting what may be the minimal number of proteins needed to form a viable reovirus particle. FAKV evolved from more complex ancestors by losing a genome segment and several virion proteins.


Asunto(s)
Culicidae/virología , Genoma Viral , Reoviridae/genética , Reoviridae/aislamiento & purificación , Animales , Camerún , Línea Celular , Análisis por Conglomerados , Microscopía por Crioelectrón , Efecto Citopatogénico Viral , Evolución Molecular , Especificidad del Huésped , Sustancias Macromoleculares/ultraestructura , Masculino , Ratones , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Reoviridae/fisiología , Reoviridae/ultraestructura , Análisis de Secuencia de ADN , Proteínas Estructurales Virales/ultraestructura , Virión/ultraestructura , Cultivo de Virus
20.
J Gen Virol ; 95(Pt 2): 481-485, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24262627

RESUMEN

Pools of mosquitoes were tested for insect-specific viruses using cytopathic effect (CPE) assays on Aedes albopictus (C6/36) cells. Illumina sequencing of RNA from pool TR7094, which produced extensive CPE 2 days post-infection, yielded the complete genome sequences of a previously unknown Bunyavirus, designated Cumuto virus (CUMV), and a second virus designated Wallerfield virus (WALV). WALV shared highest amino acid identity (60.1 %) with Dezidougou virus from Côte d'Ivoire, a positive-sense, single-strand RNA, insect-specific virus belonging to the newly proposed genus Negevirus associated with mosquitoes and phlebotomine sandflies. The S, M and L segments of CUMV were most closely related to those of Gouleako virus, also from Côte d'Ivoire (amino acid identities of 36 %, 38% and 54 % respectively). Neither virus produced CPE on vertebrate cells, or illness in newborn mice. Isolation and characterization of these viruses increase our knowledge of the geographical distribution, diversity and host range of mosquito-specific bunyaviruses and negeviruses.


Asunto(s)
Bunyaviridae/clasificación , Bunyaviridae/aislamiento & purificación , Culex/virología , Animales , Bunyaviridae/genética , Línea Celular , Efecto Citopatogénico Viral , Datos de Secuencia Molecular , ARN Viral/genética , Análisis de Secuencia de ADN , Trinidad y Tobago
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