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1.
J Gen Virol ; 105(9)2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39319430

RESUMEN

Fruit bats serve as an important reservoir for many zoonotic pathogens, including Nipah virus, Hendra virus, Marburg virus and Lyssavirus. To gain a deeper insight into the virological characteristics, pathogenicity and zoonotic potential of bat-borne viruses, recovery of infectious viruses from field samples is important. Here, we report the isolation and characterization of a mammalian orthoreovirus (MRV) from a large flying fox (Pteropus vampyrus) in Indonesia, which is the first detection of MRV in Southeast Asia. MRV was recovered from faecal samples of three different P. vampyrus in Central Java. Nucleotide sequence analysis revealed that the genome of the three MRV isolates shared more than 99% nucleotide sequence identity. We tentatively named one isolated strain as MRV12-52 for further analysis and characterization. Among 10 genome segments, MRV12-52 S1 and S4, which encode the cell-attachment protein and outer capsid protein, had 93.6 and 95.1% nucleotide sequence identities with known MRV strains, respectively. Meanwhile, the remaining genome segments of MRV12-52 were divergent with 72.9-80.7 % nucleotide sequence identities. Based on the nucleotide sequence of the S1 segment, MRV12-52 was grouped into serotype 2, and phylogenetic analysis demonstrated evidence of past reassortment events. In vitro characterization of MRV12-52 showed that the virus efficiently replicated in BHK-21, HEK293T and A549 cells. In addition, experimental infection of laboratory mice with MRV12-52 caused severe pneumonia with 75% mortality. This study highlights the presence of pathogenic MRV in Indonesia, which could serve as a potential animal and public health concern.


Asunto(s)
Quirópteros , Heces , Genoma Viral , Orthoreovirus de los Mamíferos , Filogenia , Infecciones por Reoviridae , Animales , Quirópteros/virología , Indonesia , Infecciones por Reoviridae/virología , Infecciones por Reoviridae/veterinaria , Ratones , Heces/virología , Orthoreovirus de los Mamíferos/genética , Orthoreovirus de los Mamíferos/aislamiento & purificación , Orthoreovirus de los Mamíferos/clasificación , Humanos , Análisis de Secuencia de ADN
2.
J Virol ; 97(1): e0145522, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36633410

RESUMEN

Rotavirus A (RVA) causes diarrheal disease in humans and various animals. Recent studies have identified bat and rodent RVAs with evidence of zoonotic transmission and genome reassortment. However, the virological properties of bat and rodent RVAs with currently identified genotypes still need to be better clarified. Here, we performed virus isolation-based screening for RVA in animal specimens and isolated RVAs (representative strains: 16-06 and MpR12) from Egyptian fruit bat and Natal multimammate mouse collected in Zambia. Whole-genome sequencing and phylogenetic analysis revealed that the genotypes of bat RVA 16-06 were identical to that of RVA BATp39 strain from the Kenyan fruit bat, which has not yet been characterized. Moreover, all segments of rodent RVA MpR12 were highly divergent and assigned to novel genotypes, but RVA MpR12 was phylogenetically closer to bat RVAs than to other rodent RVAs, indicating a unique evolutionary history. We further investigated the virological properties of the isolated RVAs. In brief, we found that 16-06 entered cells by binding to sialic acids on the cell surface, while MpR12 entered in a sialic acid-independent manner. Experimental inoculation of suckling mice with 16-06 and MpR12 revealed that these RVAs are causative agents of diarrhea. Moreover, 16-06 and MpR12 demonstrated an ability to infect and replicate in a 3D-reconstructed primary human intestinal epithelium with comparable efficiency to the human RVA. Taken together, our results detail the unique genetic and virological features of bat and rodent RVAs and demonstrate the need for further investigation of their zoonotic potential. IMPORTANCE Recent advances in nucleotide sequence detection methods have enabled the detection of RVA genomes from various animals. These studies have discovered multiple divergent RVAs and have resulted in proposals for the genetic classification of novel genotypes. However, most of these RVAs have been identified via dsRNA viral genomes and not from infectious viruses, and their virological properties, such as cell/host tropisms, transmissibility, and pathogenicity, are unclear and remain to be clarified. Here, we successfully isolated RVAs with novel genome constellations from three bats and one rodent in Zambia. In addition to whole-genome sequencing, the isolated RVAs were characterized by glycan-binding affinity, pathogenicity in mice, and infectivity to the human gut using a 3D culture of primary intestinal epithelium. Our study reveals the first virological properties of bat and rodent RVAs with high genetic diversity and unique evolutional history and provides basic knowledge to begin estimating the potential of zoonotic transmission.


Asunto(s)
Quirópteros , Murinae , Infecciones por Rotavirus , Rotavirus , Animales , Quirópteros/virología , Diarrea/veterinaria , Diarrea/virología , Genoma Viral , Genotipo , Kenia , Filogenia , Rotavirus/genética , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/veterinaria , Murinae/virología
3.
Virol J ; 21(1): 263, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39449113

RESUMEN

BACKGROUND: Rotavirus B (RVB) causes diarrhea in humans and pigs. Although various RVB strains were identified in humans and various animals globally, little is known about the epidemiology RVB infection in Africa. In this study, we attempted to examine the prevalence of RVB infection in pig populations in Zambia. METHODS: Metagenomic analyses were conducted on pig feces collected in Zambia to detect double stranded RNA viruses, including RVB. To clarify the prevalence of RVB infection in pig populations in Zambia, 147 fecal samples were screened for the RVB detection by RT-qPCR. Full genome sequence of a detected RVB was determined by Sanger sequencing and genetically analyzed. RESULTS: The metagenomic analyses revealed that RVB sequence reads and contigs of RVB were detected from one fecal sample collected from pigs in Zambia. RT-qPCR screening detected RVB genomes in 36.7% (54/147) of fecal samples. Among 54 positive samples, 13 were positive in non-diarrheal samples (n = 48, 27.1%) and 41 in diarrheal samples (n = 99, 41.4%). Genetic analyses demonstrated that all the segments of ZP18-18, except for VP4, had high nucleotide sequence identities (80.6-92.6%) with all other known RVB strains detected in pigs. In contrast, the VP4 sequence of ZP18-18 was highly divergent from other RVB strains (< 64.6% identities) and formed a distinct lineage in the phylogenetic tree. Notably, the VP8 subunit of the VP4 showed remarkably low amino acid identities (33.3%) to those of known RVB strains, indicating that the VP8 subunit of ZP18-18 was unique among RVB strains. According to the whole genome classification for RVB, ZP18-18 was assigned to a genotype constellation, G18-P[9]-I12-R4-C4-M4-A8-N10-T5-E4-H7 with the newly established VP4 genotype P[9]. CONCLUSIONS: This current study updates the geographical distribution and the genetic diversity of RVB. Given the lack of information regarding RVB in Africa, further RVB surveillance is required to assess the potential risk to humans and animals.


Asunto(s)
Proteínas de la Cápside , Heces , Genoma Viral , Genotipo , Filogenia , Infecciones por Rotavirus , Rotavirus , Enfermedades de los Porcinos , Animales , Porcinos , Zambia/epidemiología , Rotavirus/genética , Rotavirus/clasificación , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/virología , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/epidemiología , Heces/virología , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/epidemiología , Proteínas de la Cápside/genética , Genoma Viral/genética , Diarrea/virología , Diarrea/veterinaria , Diarrea/epidemiología , Análisis de Secuencia de ADN , ARN Viral/genética , Metagenómica , Prevalencia
4.
Arch Virol ; 168(2): 61, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36631547

RESUMEN

Although rabies is endemic in Malawi, there have been no studies in which rabies virus was systematically investigated and characterized in multiple animal hosts in that country. In order to provide molecular epidemiological data on rabies virus in Malawi, 683 suspected rabies case reports from 2008 to 2021 were examined, and 46 (dog = 40, cow = 5, and cat = 1) viable rabies-positive brain samples archived at the Central Veterinary Laboratory (CVL), Lilongwe, Malawi, were analyzed genetically. The results showed an increase in the submission of brain samples from 2008 to 2010, with the highest number of submissions observed in 2020. Of the 683 case reports analyzed for the period under review, 38.1% (260/683) (CI: 34.44 - 41.84) were confirmed by direct fluorescent antibody test. Among the confirmed cases, 65.4% (170/260) (CI: 59.23 - 71.09) were canine rabies. Further, phylogenetic analysis revealed that sequences from different animal hosts clustered together within the Africa 1b lineage, suggesting that the strains circulating in livestock are similar to those in domestic dogs. This finding supports the hypothesis that canine rabies is spilling over to livestock and emphasizes the need for further studies to provide data for effective control of rabies in Malawi.


Asunto(s)
Enfermedades de los Perros , Virus de la Rabia , Rabia , Femenino , Bovinos , Animales , Perros , Virus de la Rabia/genética , Rabia/epidemiología , Rabia/veterinaria , Filogenia , Malaui/epidemiología , Epidemiología Molecular , Enfermedades de los Perros/epidemiología , Ganado
5.
J Gen Virol ; 101(10): 1027-1036, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32706330

RESUMEN

Mammalian orthoreovirus (MRV) has been identified in humans, livestock and wild animals; this wide host range allows individual MRV to transmit into multiple species. Although several interspecies transmission and genetic reassortment events of MRVs among humans, livestock and wildlife have been reported, the genetic diversity and geographic distribution of MRVs in Africa are poorly understood. In this study, we report the first isolation and characterization of MRVs circulating in a pig population in Zambia. In our screening, MRV genomes were detected in 19.7 % (29/147) of faecal samples collected from pigs by reverse transcription PCR. Three infectious MRV strains (MRV-85, MRV-96 and MRV-117) were successfully isolated, and their complete genomes were sequenced. Recombination analyses based on the complete genome sequences of the isolated MRVs demonstrated that MRV-96 shared the S3 segment with a different MRV isolated from bats, and that the L1 and M3 segments of MRV-117 originated from bat and human MRVs, respectively. Our results suggest that the isolated MRVs emerged through genetic reassortment events with interspecies transmission. Given the lack of information regarding MRVs in Africa, further surveillance of MRVs circulating among humans, domestic animals and wildlife is required to assess potential risk for humans and animals.


Asunto(s)
Heces/virología , Orthoreovirus de los Mamíferos/genética , Orthoreovirus de los Mamíferos/aislamiento & purificación , Infecciones por Reoviridae/veterinaria , Enfermedades de los Porcinos/virología , Porcinos/virología , Animales , Animales Salvajes/clasificación , Animales Salvajes/virología , Quirópteros/virología , Genoma Viral , Especificidad del Huésped , Filogenia , Prevalencia , Virus Reordenados/genética , Recombinación Genética , Infecciones por Reoviridae/epidemiología , Infecciones por Reoviridae/virología , Enfermedades de los Porcinos/epidemiología , Proteínas Virales/genética , Secuenciación Completa del Genoma , Zambia/epidemiología
6.
Emerg Infect Dis ; 25(8): 1577-1580, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31146800

RESUMEN

We detected Marburg virus genome in Egyptian fruit bats (Rousettus aegyptiacus) captured in Zambia in September 2018. The virus was closely related phylogenetically to the viruses that previously caused Marburg outbreaks in the Democratic Republic of the Congo. This finding demonstrates that Zambia is at risk for Marburg virus disease.


Asunto(s)
Quirópteros/virología , Enfermedad del Virus de Marburg/virología , Marburgvirus , Animales , Genes Virales , Humanos , Enfermedad del Virus de Marburg/diagnóstico , Enfermedad del Virus de Marburg/epidemiología , Marburgvirus/clasificación , Marburgvirus/genética , Marburgvirus/aislamiento & purificación , Filogenia , Prevalencia , Vigilancia en Salud Pública , ARN Viral , Zambia/epidemiología
7.
J Infect Dis ; 218(suppl_5): S312-S317, 2018 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-29889270

RESUMEN

Bats are suspected to play important roles in the ecology of filoviruses, including ebolaviruses and marburgviruses. A cave-dwelling fruit bat, Rousettus aegyptiacus, has been shown to be a reservoir of marburgviruses. Using an enzyme-linked immunosorbent assay with the viral glycoprotein antigen, we detected immunoglobulin G antibodies specific to multiple filoviruses in 158 of 290 serum samples of R aegyptiacus bats captured in Zambia during the years 2014-2017. In particular, 43.8% of the bats were seropositive to marburgvirus, supporting the notion that this bat species continuously maintains marburgviruses as a reservoir. Of note, distinct peaks of seropositive rates were repeatedly observed at the beginning of rainy seasons, suggesting seasonality of the presence of newly infected individuals in this bat population. These data highlight the need for continued monitoring of filovirus infection in this bat species even in countries where filovirus diseases have not been reported.


Asunto(s)
Quirópteros/sangre , Quirópteros/inmunología , Infecciones por Filoviridae/sangre , Infecciones por Filoviridae/inmunología , Filoviridae/inmunología , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Quirópteros/virología , Reservorios de Enfermedades/virología , Femenino , Infecciones por Filoviridae/virología , Glicoproteínas/sangre , Glicoproteínas/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Estudios Seroepidemiológicos , Zambia
8.
J Vet Med Sci ; 86(8): 906-910, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-38925932

RESUMEN

Sarcocystis spp. cause pigeon protozoan encephalitis, a neuronal disease. A female pigeon exhibiting torticollis had a necrotic area in the cerebral hemisphere surrounded by lesions with perivascular cuffing, gliosis, granulomatous foci, and meningitis. Non-necrotic lesions were also observed in the brainstem. Intact and degenerative schizonts were observed within the neuropils and neurons in the lesions. Deoxyribonucleic acid (DNA) was extracted from paraffin-embedded brain tissues and genetically analyzed after gel electrophoresis to determine Sarcocystis spp. using specific primer sets for 28S ribosomal ribonucleic acid and internal transcribed spacer region-1. DNA sequencing confirmed a significant homology with S. calchasi. This is the first report of meningoencephalitis with malacia caused by S. calchasi in a rock pigeon in Japan.


Asunto(s)
Enfermedades de las Aves , Columbidae , Meningoencefalitis , Sarcocystis , Sarcocistosis , Animales , Sarcocystis/aislamiento & purificación , Sarcocystis/genética , Columbidae/parasitología , Sarcocistosis/veterinaria , Sarcocistosis/parasitología , Sarcocistosis/patología , Femenino , Japón , Enfermedades de las Aves/parasitología , Enfermedades de las Aves/patología , Meningoencefalitis/veterinaria , Meningoencefalitis/parasitología , Meningoencefalitis/patología , Encéfalo/patología , Encéfalo/parasitología
9.
J Vet Med Sci ; 85(8): 832-836, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37344389

RESUMEN

We focused on streptomycin resistance because of the high percentage of streptomycin-resistant Escherichia coli concerning the amount used of streptomycin. Antimicrobial resistance and horizontal transfer were identified in 117 isolates of coliform bacteria from chicken meat to identify the factors that increase streptomycin resistance. Escherichia (45 isolates) was the predominant genus. Most streptomycin-resistant Escherichia isolates were resistant to other antimicrobials (17/18), suggesting that using various antimicrobials could select streptomycin-resistant Escherichia isolates. Resistance was transferred from 7 out of the 18 streptomycin-resistant isolates. The transconjugants acquired strA/strB (7/7), blaTEM (5/7), aphA1 (5/7), tetB (3/7), dfrA14 (1/7) and/or dfrA17 (1/7). The co-resistance of streptomycin resistance with other resistances would also increase streptomycin resistance.


Asunto(s)
Escherichia coli , Estreptomicina , Animales , Estreptomicina/farmacología , Antibacterianos/farmacología , Pollos/microbiología , Japón , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple/genética , Carne/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria
10.
Sci Rep ; 13(1): 18165, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37875565

RESUMEN

Mosquitoes interact with various organisms in the environment, and female mosquitoes in particular serve as vectors that directly transmit a number of microorganisms to humans and animals by blood-sucking. Comprehensive analysis of mosquito-borne viruses has led to the understanding of the existence of diverse viral species and to the identification of zoonotic arboviruses responsible for significant outbreaks and epidemics. In the present study on mosquito-borne bunyaviruses we employed a broad-spectrum RT-PCR approach and identified eighteen different additional species in the Phenuiviridae family and also a number of related but unclassified bunyaviruses in mosquitoes collected in Zambia. The entire RNA genome segments of the newly identified viruses were further analyzed by RNA sequencing with a ribonuclease R (RNase R) treatment to reduce host-derived RNAs and enrich viral RNAs, taking advantage of the dsRNA panhandle structure of the bunyavirus genome. All three or four genome segments were identified in eight bunyavirus species. Furthermore, L segments of three different novel viruses related to the Leishbunyaviridae were found in mosquitoes together with genes from the suspected host, the Crithidia parasite. In summary, our virus detection approach using a combination of broad-spectrum RT-PCR and RNA sequencing analysis with a simple virus enrichment method allowed the discovery of novel bunyaviruses. The diversity of bunyaviruses is still expanding and studies on this will allow a better understanding of the ecology of hematophagous mosquitoes.


Asunto(s)
Arbovirus , Culicidae , Orthobunyavirus , Virus ARN , Animales , Humanos , Femenino , Mosquitos Vectores , Orthobunyavirus/genética , Virus ARN/genética , Arbovirus/genética
11.
Microorganisms ; 11(1)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36677492

RESUMEN

Relapsing fever (RF) is an arthropod-borne disease caused by Borrelia spirochete, which is one of the major public health concerns in endemic regions including Africa. However, information on Borrelia spirochetes is limited in Zambia. Here, we investigate the Borrelia spirochetes harbored by Ornithodoros ticks in Zambian National Parks. We analyzed 182 DNA samples pooled from 886 Ornithodoros ticks. Of these, 43 tested positive, and their sequence revealed that the ticks harbored both Old and New World RF borreliae. This research presents the first evidence of Old-World RF borreliae in Zambia. The New World RF borreliae detected herein differed from the Candidatus Borrelia fainii previously reported in Zambia and were closely related to the pathogenic Borrelia sp. VS4 identified in Tanzania. Additionally, Borrelia theileri was recently reported in Zambia. Hence, at least four different Borrelia species occur in Zambia, and the organisms causing relapsing fever there might be more complex than previously thought. We empirically confirmed that real-time PCR with TaqMan minor groove binder probes accurately and simultaneously detected both Old and New World RF. In this manner, they could facilitate quantitative analyses of both types of RF borreliae. Subsequent investigations should endeavor to isolate the aforementioned Borrelia spp. and perform serosurveys on patients with RF.

12.
Viruses ; 15(6)2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37376669

RESUMEN

Bats are of significant interest as reservoirs for various zoonotic viruses with high diversity. During the past two decades, many herpesviruses have been identified in various bats worldwide by genetic approaches, whereas there have been few reports on the isolation of infectious herpesviruses. Herein, we report the prevalence of herpesvirus infection of bats captured in Zambia and genetic characterization of novel gammaherpesviruses isolated from striped leaf-nosed bats (Macronycteris vittatus). By our PCR screening, herpesvirus DNA polymerase (DPOL) genes were detected in 29.2% (7/24) of Egyptian fruit bats (Rousettus aegyptiacus), 78.1% (82/105) of Macronycteris vittatus, and one Sundevall's roundleaf bat (Hipposideros caffer) in Zambia. Phylogenetic analyses of the detected partial DPOL genes revealed that the Zambian bat herpesviruses were divided into seven betaherpesvirus groups and five gammaherpesvirus groups. Two infectious strains of a novel gammaherpesvirus, tentatively named Macronycteris gammaherpesvirus 1 (MaGHV1), were successfully isolated from Macronycteris vittatus bats, and their complete genomes were sequenced. The genome of MaGHV1 encoded 79 open reading frames, and phylogenic analyses of the DNA polymerase and glycoprotein B demonstrated that MaGHV1 formed an independent lineage sharing a common origin with other bat-derived gammaherpesviruses. Our findings provide new information regarding the genetic diversity of herpesviruses maintained in African bats.


Asunto(s)
Quirópteros , Gammaherpesvirinae , Herpesviridae , Animales , Filogenia , Zambia/epidemiología , Herpesviridae/genética
13.
Pathogens ; 12(10)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37887715

RESUMEN

Rotavirus is a major cause of diarrhea globally in animals and young children under 5 years old. Here, molecular detection and genetic characterization of porcine rotavirus in smallholder and commercial pig farms in the Lusaka Province of Zambia were conducted. Screening of 148 stool samples by RT-PCR targeting the VP6 gene revealed a prevalence of 22.9% (34/148). Further testing of VP6-positive samples with VP7-specific primers produced 12 positives, which were then Sanger-sequenced. BLASTn of the VP7 positives showed sequence similarity to porcine and human rotavirus strains with identities ranging from 87.5% to 97.1%. By next-generation sequencing, the full-length genetic constellation of the representative strains RVA/pig-wt/ZMB/LSK0137 and RVA/pig-wt/ZMB/LSK0147 were determined. Genotyping of these strains revealed a known Wa-like genetic backbone, and their genetic constellations were G4-P[6]-I5-R1-C1-M1-A8-N1-T1-E1-H1 and G9-P[13]-I5-R1-C1-M1-A8-N1-T1-E1-H1, respectively. Phylogenetic analysis revealed that these two viruses might have their ancestral origin from pigs, though some of their gene segments were related to human strains. The study shows evidence of reassortment and possible interspecies transmission between pigs and humans in Zambia. Therefore, the "One Health" surveillance approach for rotavirus A in animals and humans is recommended to inform the design of effective control measures.

14.
Arch Virol ; 157(11): 2223-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22814699

RESUMEN

The JM1/1 strain of fowl adenovirus (FAV) serotype 1 isolated from gizzard erosion was used to investigate the biology of FAV in homologous (susceptible) and heterologous cells. The FAV JM1/1 strain is capable of efficient multiplication in primary chicken kidney (CK) cells, but not in Crandell-Rees feline kidney (CRFK) cells or Vero cells. FAV adsorption in heterologous cells was slightly higher than in CK cells. An early gene encoding a DNA-binding protein and a late gene encoding the hexon protein were expressed in CK cells. Only the early gene was expressed in Vero cells. Neither of these genes was expressed in CRFK cells. These results suggest that the virus was unable to multiply effectively due to suppression of viral gene expression in the heterologous cells used in this study.


Asunto(s)
Adenoviridae/fisiología , Especificidad del Huésped , Replicación Viral , Adenoviridae/crecimiento & desarrollo , Animales , Gatos , Células Cultivadas , Pollos , Chlorocebus aethiops , Perfilación de la Expresión Génica , Acoplamiento Viral
15.
Biocontrol Sci ; 17(2): 87-91, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22790845

RESUMEN

Feline calicivirus (FCV) is a pathogenic microorganism that causes upper respiratory diseases in cats. Recently, an FCV infection with a high mortality rate has been confirmed, and there is need to develop a treatment for cases of acute infection. We evaluated whether the replication of FCV could be prevented by RNA interference. For this study, we designed an siRNA targeted to the polymerase region of the strain FCV-B isolated from a cat that died after exhibiting neurological symptoms. Cells transfected with siR-pol dose-dependently suppressed the replication of FCV-B. siR-pol suppressed its replication by suppressing the target viral RNA.


Asunto(s)
Infecciones por Caliciviridae/veterinaria , Calicivirus Felino/fisiología , Enfermedades de los Gatos/virología , Genes pol/genética , ARN Interferente Pequeño/genética , Replicación Viral/genética , Animales , Infecciones por Caliciviridae/terapia , Infecciones por Caliciviridae/virología , Calicivirus Felino/genética , Calicivirus Felino/aislamiento & purificación , Enfermedades de los Gatos/mortalidad , Enfermedades de los Gatos/terapia , Gatos , Línea Celular , Efecto Citopatogénico Viral , Genoma Viral/genética , Interferencia de ARN , ARN Viral/genética , Factores de Tiempo , Transfección/veterinaria
16.
Virology ; 575: 10-19, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35987079

RESUMEN

Nelson Bay orthoreovirus (NBV) is an emerging bat-borne virus and causes respiratory tract infections in humans sporadically. Over the last two decades, several strains genetically related to NBV were isolated from humans and various bat species, predominantly in Southeast Asia (SEA), suggesting a high prevalence of the NBV species in this region. In this study, an orthoreovirus (ORV) belonging to the NBV species was isolated from Indonesian fruit bats' feces, tentatively named Paguyaman orthoreovirus (PgORV). Serological studies revealed that 81.2% (108/133) of Indonesian fruit bats sera had neutralizing antibodies against PgORV. Whole-genome sequencing and phylogenetic analysis of PgORV suggested the occurrence of past reassortments with other NBV strains isolated in SEA, indicating the dispersal and circulation of NBV species among bats in this region. Intranasal PgORV inoculation of laboratory mice caused severe pneumonia. Our study characterized PgORV's unique genetic background and highlighted the potential risk of PgORV-related diseases in Indonesia.


Asunto(s)
Quirópteros , Orthoreovirus , Animales , Anticuerpos Neutralizantes , Humanos , Indonesia/epidemiología , Ratones , Orthoreovirus/genética , Filogenia
17.
PLoS Negl Trop Dis ; 16(6): e0010420, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35653390

RESUMEN

Rift valley fever (RVF) is a mosquito-borne disease of animals and humans. Although RVF outbreaks are usually reported at 5-15-year intervals in sub-Saharan Africa, Zambia has experienced an unusually long inter-epizootic/-epidemic period of more than three decades. However, serological evidence of RVF virus (RVFV) infection in domestic ruminants during this period underscores the need for comprehensive investigation of the mechanisms of virus perpetuation and disease emergence. Mosquitoes (n = 16,778) captured from eight of the ten provinces of Zambia between April 2014 and May 2019 were pooled (n = 961) and screened for RVFV genome by a pan-phlebo RT-PCR assay. Aedes mosquito pools (n = 85) were further screened by nested RT-PCR assay. Sera from sheep (n = 13), goats (n = 259) and wild ungulates (n = 285) were screened for RVFV antibodies by ELISA while genome detection in pooled sera (n = 276) from domestic (n = 248) and wild ungulates (n = 37) was performed by real-time RT-PCR assay. To examine the association between the long inter-epizootic period and climatic variables, we examined El Niño-Southern Oscillation indices, precipitation anomalies, and normalized difference vegetation index. We then derived RVF risk maps by exploring climatic variables that would favor emergence of primary RVFV vectors. While no RVFV genome could be detected in pooled mosquito and serum samples, seroprevalence was significantly high (OR = 8.13, 95% CI [4.63-14.25]) in wild ungulates (33.7%; 96/285) compared to domestic ruminants (5.6%; 16/272). Retrospective analysis of RVF epizootics in Zambia showed a positive correlation between anomalous precipitation (La Niña) and disease emergence. On risk mapping, whilst northern and eastern parts of the country were at high risk, domestic ruminant population density was low (< 21 animals/km2) in these areas compared to low risk areas (>21 animals/km2). Besides evidence of silent circulation of RVFV and the risk of disease emergence in some areas, wildlife may play a role in the maintenance of RVFV in Zambia.


Asunto(s)
Culicidae , Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Animales , Anticuerpos Antivirales , Brotes de Enfermedades/veterinaria , Mosquitos Vectores , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Virus de la Fiebre del Valle del Rift/genética , Rumiantes , Estudios Seroepidemiológicos , Ovinos , Zambia/epidemiología
18.
Transbound Emerg Dis ; 69(4): e931-e943, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34724353

RESUMEN

Influenza A viruses (IAVs) cause highly contagious respiratory diseases in humans and animals. In 2009, a swine-origin pandemic H1N1 IAV, designated A(H1N1)pdm09 virus, spread worldwide, and has since frequently been introduced into pig populations. Since novel reassortant IAVs with pandemic potential may emerge in pigs, surveillance for IAV in pigs is therefore necessary not only for the pig industry but also for public health. However, epidemiological information on IAV infection of pigs in Africa remains sparse. In this study, we collected 246 serum and 605 nasal swab samples from pigs in Zambia during the years 2011-2018. Serological analyses revealed that 49% and 32% of the sera collected in 2011 were positive for hemagglutination-inhibition (HI) and neutralizing antibodies against A(H1N1)pdm09 virus, respectively, whereas less than 5.3% of sera collected during the following period (2012-2018) were positive in both serological tests. The positive rate and the neutralization titres to A(H1N1)pdm09 virus were higher than those to classical swine H1N1 and H1N2 IAVs. On the other hand, the positive rate for swine H3N2 IAV was very low in the pig population in Zambia in 2011-2018 (5.3% and 0% in HI and neutralization tests, respectively). From nasal swab samples, we isolated one H3N2 and eight H1N1 IAV strains with an isolation rate of 1.5%. Phylogenetic analyses of all eight gene segments revealed that the isolated IAVs were closely related to human IAV strains belonging to A(H1N1)pdm09 and seasonal H3N2 lineages. Our findings indicate that reverse zoonotic transmission from humans to pigs occurred during the study period in Zambia and highlight the need for continued surveillance to monitor the status of IAVs circulating in swine populations in Africa.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Animales , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Virus de la Influenza A/genética , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Filogenia , Porcinos , Zambia/epidemiología
19.
Ticks Tick Borne Dis ; 12(4): 101720, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33865179

RESUMEN

Ticks (Ixodidae and Argasidae) are important arthropod vectors of various pathogens that cause human and animal infectious diseases. Many previously published studies on tick-borne pathogens focused on those transmitted by ixodid ticks. Although there are increasing reports of viral pathogens associated with argasid ticks, information on bacterial pathogens they transmit is scarce. The aim of this molecular study was to detect and characterize Rickettsia and Anaplasmataceae in three different argasid tick species, Ornithodoros faini, Ornithodoros moubata, and Argas walkerae collected in Zambia. Rickettsia hoogstraalii and Rickettsia lusitaniae were detected in 77 % (77/100) of Ar. walkerae and 10 % (5/50) of O. faini, respectively. All O. moubata pool samples (n = 124) were negative for rickettsial infections. Anaplasmataceae were detected in 63 % (63/100) of Ar. walkerae and in 82.2 % (102/124) of O. moubata pools, but not in O. faini. Phylogenetic analysis based on the concatenated sequences of 16S rRNA and groEL genes revealed that Anaplasma spp. detected in the present study were distinct from previously validated Anaplasma species, indicating that the current knowledge on the diversity and vector range of Anaplasma spp. is incomplete. Our findings highlight new geographical records of R. lusitaniae and R. hoogstraalii and confirm that the wide geographic distribution of these species includes the African continent. The data presented here increase our knowledge on argasid tick-borne bacteria and contribute toward understanding their epidemiology.


Asunto(s)
Anaplasma/aislamiento & purificación , Argas/microbiología , Ornithodoros/microbiología , Rickettsia/aislamiento & purificación , Animales , Zambia
20.
Emerg Microbes Infect ; 10(1): 2169-2172, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34736356

RESUMEN

While evidence suggests presence of HEV infection in humans in Zambia, currently, there is no information on its occurrence in domestic pigs. Here, we investigated the presence of HEV antibodies and genome in domestic pigs in Zambia. Sera (n = 484) from domestic pigs were screened for antibodies against HEV by ELISA while genome detection in fecal (n = 25) and liver (n = 100) samples from slaughter pigs was conducted using nested RT-PCR assay. Overall, seroprevalence was 47.7% (231/484) while zoonotic genotype 3 HEV RNA was detected in 16.0% (20/125) of slaughtered pigs. This is the first report to highlight occurrence of HEV infection in domestic pigs in Zambia. This finding suggests possible contamination of the pork supply chain. Moreover, there is a potential risk of zoonotic transmission of HEV to abattoir workers, pig farmers and handlers.


Asunto(s)
Virus de la Hepatitis E/inmunología , Hepatitis E/veterinaria , Enfermedades de los Porcinos/virología , Mataderos , Animales , Anticuerpos Antihepatitis/sangre , Hepatitis E/sangre , Hepatitis E/epidemiología , Hepatitis E/virología , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/aislamiento & purificación , Estudios Seroepidemiológicos , Sus scrofa/sangre , Sus scrofa/virología , Porcinos , Enfermedades de los Porcinos/sangre , Enfermedades de los Porcinos/epidemiología , Zambia/epidemiología
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