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1.
Acta Trop ; 257: 107298, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38909726

RESUMEN

Bats from three provinces in Vietnam (Lai Chau, Son La, and Dong Thap) were examined for the presence of pathogenic Leptospira or specific antibodies using polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and microscopic agglutination test (MAT). Tissue specimens from 298 bats belonging to 11 species were analyzed using a real-time PCR assay specific for leptospires of pathogenic species. Leptospiral DNA was identified in 40 bats from following species: Rousettus amplexicaudatus (5/9; 55.5 %), Rousettus leschenaultii (17/42; 40.4 %), Myotis hasseltii (8/25; 32 %), Taphozous longimanus (3/12; 25 %), and Eonycteris spelaea (7/32; 21.9 %). Based on secY phylogeny, sequences from M. hasseltii bore a strong resemblance to L. borgpetersenii. Sequences from other species revealed unique lineages: one of them resembled Leptospira sp., previously identified in Rousettus madagascariensis (Madagascar) and Rousettus aegyptiacus (South Africa); the second lineage showed close relation to L. kirshneri; and the third held an intermediary position between L. noguchii and L. interrogans. Through ELISA, anti-Leptospira antibodies were found in 83 of 306 bats, with the highest seroprevalence observed in R. leschenaultii (44/48; 91.6 %), R. amplexicaudatus (6/8; 75 %), and E. spelaea (19/25; 76 %). 66 of these ELISA-positive samples were tested using MAT; 41 of them were confirmed in MAT as positive. The predominant serogroups in our study were Tarassovi and Mini.


Asunto(s)
Anticuerpos Antibacterianos , Quirópteros , Ensayo de Inmunoadsorción Enzimática , Leptospira , Leptospirosis , Filogenia , Animales , Quirópteros/microbiología , Vietnam/epidemiología , Leptospirosis/veterinaria , Leptospirosis/epidemiología , Leptospirosis/microbiología , Leptospira/genética , Leptospira/clasificación , Leptospira/aislamiento & purificación , Leptospira/inmunología , Anticuerpos Antibacterianos/sangre , ADN Bacteriano/genética , Pruebas de Aglutinación , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
2.
Viruses ; 15(9)2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37766193

RESUMEN

A new filovirus named Menglà virus was found in bats in southern China in 2015. This species has been assigned to the new genus Dianlovirus and has only been detected in China. In this article, we report the detection of filoviruses in bats captured in Vietnam. We studied 248 bats of 15 species caught in the provinces of Lai Chau and Son La in northern Vietnam and in the province of Dong Thap in the southern part of the country. Filovirus RNA was found in four Rousettus leschenaultii and one Rousettus amplexicaudatus from Lai Chau Province. Phylogenetic analysis of the polymerase gene fragment showed that three positive samples belong to Dianlovirus, and two samples form a separate clade closer to Orthomarburgvirus. An enzyme-linked immunosorbent assay showed that 9% of Rousettus, 13% of Eonycteris, and 10% of Cynopterus bats had antibodies to the glycoprotein of marburgviruses.


Asunto(s)
Quirópteros , Filoviridae , Marburgvirus , Animales , Vietnam/epidemiología , Filogenia
3.
Viruses ; 14(9)2022 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-36146715

RESUMEN

Members of the jingmenviruses group have been found in arthropods and mammals on all continents except Australia and Antarctica. Two viruses of this group were isolated from patients with fever after a tick bite. Using a nested RT-PCR assay targeting a jingmenvirus polymerase gene fragment, we screened ticks collected in seven regions of Russia and found that the abundant jingmenvirus-positive were of Ixodes ricinus species, with the prevalence ranging from 19.8% to 34.3%. In all cases, DNase/RNase treatment suggested that the detected molecule was DNA and subsequent next generation sequencing (NGS) proved that the viral polymerase gene was integrated in the I. ricinus genome. The copy number of the integrated polymerase gene was quantified by qPCR relative to the ITS2 gene and estimated as 1.32 copies per cell. At least three different genetic variants of the integrated polymerase gene were found in the territory of Russia. Phylogenetic analysis of the integrated jingmenvirus polymerase gene showed the highest similarity with the sequence of the correspondent gene obtained in Serbia from I. ricinus.


Asunto(s)
Ixodes , Animales , Desoxirribonucleasas , Genoma de los Insectos , Humanos , Mamíferos , Filogenia , Reacción en Cadena de la Polimerasa , Ribonucleasas
4.
Parasitol Res ; 120(5): 1563-1570, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33788020

RESUMEN

Rhipicephalus microplus is an ixodid tick with a pantropical distribution that represents a serious threat to livestock. West Africa was free of this tick until 2007, when its introduction into Benin was reported. Shortly thereafter, further invasion of this tick species into other West African countries was identified. In this paper, we describe the first detection of R. microplus in Guinea and list the vector-borne haemoparasites that were detected in the invading and indigenous Boophilus species. In 2018, we conducted a small-scale survey of ticks infesting cattle in three administrative regions of Guinea: N`Zerekore, Faranah, and Kankan. The tick species were identified by examining their morphological characteristics and by sequencing their COI gene and ITS-2 gene fragments. R. microplus was found in each studied region. In the ticks, we found the DNA of Babesia bigemina, Anaplasma marginale, Anaplasma platys, and Ehrlichia sp. The results of this study indicate that R. microplus was introduced into Guinea in association with cows from Mali and/or the Ivory Coast.


Asunto(s)
Anaplasma marginale/aislamiento & purificación , Anaplasma/aislamiento & purificación , Babesia/aislamiento & purificación , Ehrlichia/aislamiento & purificación , Rhipicephalus/microbiología , Rhipicephalus/parasitología , Anaplasma/genética , Anaplasma marginale/genética , Animales , Babesia/genética , Benin , Bovinos , Enfermedades de los Bovinos/parasitología , Côte d'Ivoire , Ehrlichia/genética , Femenino , Guinea , Ganado/parasitología , Infestaciones por Garrapatas/veterinaria
5.
Acta Trop ; 214: 105790, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309594

RESUMEN

Ngari virus is a mosquito-borne virus belonging to the genus Orthobunyavirus (Peribunyaviridae family). This virus is pathogenic to humans and causes severe illness. Ngari virus is present in several African countries, including Madagascar. Here, we report the detection of Ngari virus in ixodid ticks collected from cows in Guinea. A tick survey was conducted in March-November of 2018 in six regions of Guinea. The sample comprised 710 pools, with a total of 2067 ticks belonging to five species collected from 197 cows. At the initial stage, we screened a subsample of tick pools of vector-borne viruses with a multiplex genus-specific primer panel. In the second stage of the study, we narrowed the search and screened all the samples by qPCR for the detection of Ngari virus. All positive samples were sequenced with primers flanking Ngari virus-specific fragments on the S and M segments. We found Ngari virus in 12 pools that were formed from engorged ticks collected from livestock in three villages of the Kindia and Kankan regions. Sequencing of the S and M segments confirmed that the detected viruses belong to Ngari virus, and the viruses were most similar to the strain Adrar, which was isolated in Mauritania. We detected viral RNA in ticks of the following species: Amblyomma variegatum, Rhipicephalus geigyi, and Rh. (Boophilus) spp. There is no evidence that ixodid ticks are competent vectors of the Ngari virus. Most likely, the ticks obtained the virus through blood from an infected host. The study of engorged ticks can be recommended as a simpler approach for the wide screening of the Ngari virus and subsequent testing of cattle and mosquitos in those locations where the PCR-positive ticks were collected.


Asunto(s)
Infecciones por Bunyaviridae/veterinaria , Enfermedades de los Bovinos/epidemiología , Ixodidae/virología , Orthobunyavirus/aislamiento & purificación , Infestaciones por Garrapatas/veterinaria , Animales , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/transmisión , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/transmisión , Enfermedades de los Bovinos/virología , Femenino , Guinea/epidemiología , Humanos , Orthobunyavirus/genética , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
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