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1.
J Gen Virol ; 105(4)2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38687001

RESUMEN

Nairoviridae is a family for negative-sense RNA viruses with genomes of about 17.2-21.1 kb. These viruses are maintained in and/or transmitted by arthropods among birds, reptiles and mammals. Norwaviruses and orthonairoviruses can cause febrile illness in humans. Several orthonairoviruses can infect mammals, causing mild, severe and sometimes, fatal diseases. Nairovirids produce enveloped virions containing two or three single-stranded RNA segments with open reading frames that encode a nucleoprotein (N), sometimes a glycoprotein precursor (GPC), and a large (L) protein containing an RNA-directed RNA polymerase (RdRP) domain. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) report on the family Nairoviridae, which is available at www.ictv.global/report/nairoviridae.


Asunto(s)
Genoma Viral , Animales , Humanos , Sistemas de Lectura Abierta , Proteínas Virales/genética , Nairovirus/genética , Nairovirus/clasificación , Nairovirus/aislamiento & purificación , ARN Viral/genética , Filogenia , Virión/ultraestructura , ARN Polimerasa Dependiente del ARN/genética
2.
Pathogens ; 13(3)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38535604

RESUMEN

From 1993 to 1994, 64 free-ranging elephants (Loxodonta africana) succumbed to encephalomyocarditis in the Kruger National Park, South Africa, of which 83% were adult bulls. Mastomys rodents were implicated as the reservoir host of the Encephalomyocarditis virus (EMCV) based on serology and RT-PCR. However, in the absence of sequence-confirmation of both the virus and the rodent host, definitive links between the elephant outbreak strains and rodent reservoir could not be established. In this study, we generate the first reference genome sequences for three historical EMCVs isolated from two Mastomys rodents and one Mastomys-associated mite, Laelaps muricola, in Gauteng Province, South Africa, in 1961. In addition, near-complete genome sequences were generated for two elephant outbreak virus strains, for which data were previously limited to the P1 and 3D genome regions. The consensus sequence of each virus was determined using a PCR-Sanger sequencing approach. Phylogenetic analysis confirmed the three near-identical (99.95-99.97%) Mastomys-associated viruses to be sister to the two near-identical (99.85%) elephant outbreak strains, differing from each other at 6.4% of sites across the ~7400-nucleotide region characterised. This study demonstrates a link between Mastomys-associated viruses and the historical elephant outbreak strains and implicates Mastomys as reservoirs of EMCV in South Africa.

3.
J Gen Virol ; 105(2)2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305775

RESUMEN

Filoviridae is a family of negative-sense RNA viruses with genomes of about 13.1-20.9 kb that infect fish, mammals and reptiles. The filovirid genome is a linear, non-segmented RNA with five canonical open reading frames (ORFs) that encode a nucleoprotein (NP), a polymerase cofactor (VP35), a glycoprotein (GP1,2), a transcriptional activator (VP30) and a large protein (L) containing an RNA-directed RNA polymerase (RdRP) domain. All filovirid genomes encode additional proteins that vary among genera. Several filovirids (e.g., Ebola virus, Marburg virus) are pathogenic for humans and highly virulent. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Filoviridae, which is available at www.ictv.global/report/filoviridae.


Asunto(s)
Ebolavirus , Marburgvirus , Rhabdoviridae , Animales , Humanos , Ebolavirus/genética , Rhabdoviridae/genética , Filogenia , Genoma Viral , Replicación Viral , Mamíferos/genética
4.
Sci Rep ; 13(1): 15829, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37739999

RESUMEN

Novel coronavirus species of public health and veterinary importance have emerged in the first two decades of the twenty-first century, with bats identified as natural hosts for progenitors of many coronaviruses. Targeted wildlife surveillance is needed to identify the factors involved in viral perpetuation within natural host populations, and drivers of interspecies transmission. We monitored a natural colony of Egyptian rousette bats at monthly intervals across two years to identify circulating coronaviruses, and to investigate shedding dynamics and viral maintenance within the colony. Three distinct lineages were detected, with different seasonal temporal excretion dynamics. For two lineages, the highest periods of coronavirus shedding were at the start of the year, when large numbers of bats were found in the colony. Highest peaks for a third lineage were observed towards the middle of the year. Among individual bat-level factors (age, sex, reproductive status, and forearm mass index), only reproductive status showed significant effects on excretion probability, with reproductive adults having lower rates of detection, though factors were highly interdependent. Analysis of recaptured bats suggests that viral clearance may occur within one month. These findings may be implemented in the development of risk reduction strategies for potential zoonotic coronavirus transmission.


Asunto(s)
Líquidos Corporales , COVID-19 , Quirópteros , Animales , Animales Salvajes
5.
Arch Virol ; 168(8): 220, 2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37537381

RESUMEN

The International Committee on Taxonomy of Viruses (ICTV) Filoviridae Study Group continues to prospectively refine the established nomenclature for taxa included in family Filoviridae in an effort to decrease confusion of genus, species, and virus names and to adhere to amended stipulations of the International Code of Virus Classification and Nomenclature (ICVCN). Recently, the genus names Ebolavirus and Marburgvirus were changed to Orthoebolavirus and Orthomarburgvirus, respectively. Additionally, all established species names in family Filoviridae now adhere to the ICTV-mandated binomial format. Virus names remain unchanged and valid. Here, we outline the revised taxonomy of family Filoviridae as approved by the ICTV in April 2023.


Asunto(s)
Ebolavirus , Filoviridae , Marburgvirus , Virus
6.
Viruses ; 15(6)2023 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-37376647

RESUMEN

Rift Valley fever (RVF) is a re-emerging zoonotic disease of domestic ruminants and humans. While neighbouring countries have reported outbreaks of RVF, Ghana has not yet identified any cases. The aim of this study was to determine whether RVF virus (RVFV) was circulating in livestock and herders in the southern part of Ghana, to estimate its seroprevalence, and to identify associated risk factors. The study surveyed 165 livestock farms randomly selected from two districts in southern Ghana. Serum samples of 253 goats, 246 sheep, 220 cattle, and 157 herdsmen were tested to detect IgG and IgM antibodies against RVFV. The overall seroprevalence of anti-RVF antibodies in livestock was 13.1% and 30.9% of farms had RVFV seropositive animals. The species-specific prevalence was 24.1% in cattle, 8.5% in sheep, and 7.9% in goats. A RVFV IgG seroprevalence of 17.8% was found among the ruminant herders, with 8.3% of all herders being IgM positive. RVFV was shown, for the first time, to have been circulating in southern Ghana, with evidence of a recent outbreak in Kwahu East; however, it was clinically undetected despite significant recent human exposure. A One Health approach is recommended to better understand RVF epidemiology and socio-economic impact in Ghana.


Asunto(s)
Enfermedades de los Bovinos , Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Enfermedades de las Ovejas , Animales , Bovinos , Ovinos , Humanos , Ganado , Estudios Seroepidemiológicos , Ghana/epidemiología , Anticuerpos Antivirales , Enfermedades de las Ovejas/epidemiología , Rumiantes , Cabras , Inmunoglobulina M , Inmunoglobulina G
7.
J Med Virol ; 95(3): e28675, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36929720

RESUMEN

Japanese encephalitis virus (JEV) is the foremost cause of viral encephalitis in Southeast Asia and Australia leading to approximately 68 000 clinical cases and about 13 600-20 400 deaths annually. Vaccination is not completely sure and safe. Despite this, no specific antiviral has been available or approved for JEV infection yet and treatment is generally symptomatic. Therefore, this study aims to examine the antiviral activity of natural compounds against JEV proteins. The antiviral activity of natural compounds was investigated via molecular docking, cytopathic effect (CPE) inhibition assay, western blotting, and indirect immunofluorescence assay. Physiochemical, pharmacokinetics, and toxicity analysis were evaluated for the safety and efficacy of natural compounds. Network pharmacology-based approaches have been used to study the molecular mechanisms of drug-target interactions. Molecular docking results suggested that the NS5 protein of JEV is the major target for natural compounds. Network pharmacology-based analysis revealed that these drugs majorly target IL6, AKT1, tumor necrosis factor (TNF), and PTGS2 to regulate key immune and inflammatory pathways such as nuclear factor kappa B, PI3K-Akt, and TNF signaling, during JEV infection. Our in vitro results show that among the natural compounds, curcumin provides the highest protection against JEV infection via reducing the JEV-induced CPE (IC50 = 5.90 ± 0.44 µM/mL), and reduces the expression of NS5 protein, IL6, AKT1, TNF-α, and PTGS2. However, other natural compounds also provide protection to some extent but their efficacy is lower compared to curcumin. Therefore, this study shows that natural compounds, mainly curcumin, may offer novel therapeutic avenues for the treatment of JEV via inhibiting key viral proteins and regulating crucial host pathways involved in JEV replication.


Asunto(s)
Curcumina , Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/uso terapéutico , Simulación del Acoplamiento Molecular , Curcumina/farmacología , Curcumina/uso terapéutico , Interleucina-6 , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Replicación Viral
8.
J Med Virol ; 95(1): e27902, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35652133

RESUMEN

A multicountry outbreak of the monkeypox virus has gained global attention. As of May 25, 250 confirmed human monkeypox cases have been reported globally. Monkeypox is caused by the Monkeypox virus, which belongs to the Orthopoxvirus genus and Poxviridae family. Monkeypox is often a self-limiting infection, with symptoms lasting 2-4 weeks with the case fatality ratio around 3%-6%. Monkeypox is transmitted to humans by direct contact with an infected person or animal or contact with virus-contaminated material. Human monkeypox infections may lead to various medical complications such as fever, rash, and lymphadenopathies. Pneumonitis, encephalitis, sight-threatening keratitis, and subsequent bacterial infections are all possible complications of monkeypox. An antiviral agent developed to treat smallpox has also been approved for use in the treatment of monkeypox in the United States. Vaccines used in the smallpox eradication program also provided immunity to monkeypox. Newer vaccines have been developed, one of which has been approved for monkeypox prevention. In this study, we provide information about the recent outbreaks of human monkeypox, epidemiology, transmission pattern, possible diagnosis techniques, therapeutics, and available preventive strategies.


Asunto(s)
Mpox , Viruela , Animales , Humanos , Estados Unidos , Mpox/diagnóstico , Mpox/epidemiología , Viruela/epidemiología , Viruela/prevención & control , Monkeypox virus , Salud Pública , Brotes de Enfermedades
9.
J Med Virol ; 94(12): 5766-5779, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35945190

RESUMEN

The aim of the study was to trace and understand the origin of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through various available literatures and accessible databases. Although the world enters the third year of the coronavirus disease 2019 pandemic, health and socioeconomic impacts continue to mount, the origin and mechanisms of spill-over of the SARS-CoV-2 into humans remain elusive. Therefore, a systematic review of the literature was performed that showcased the integrated information obtained through manual searches, digital databases (PubMed, CINAHL, and MEDLINE) searches, and searches from legitimate publications (1966-2022), followed by meta-analysis. Our systematic analysis data proposed three postulated hypotheses concerning the origin of the SARS-CoV-2, which include zoonotic origin (Z), laboratory origin (L), and obscure origin (O). Despite the fact that the zoonotic origin for SARS-CoV-2 has not been conclusively identified to date, our data suggest a zoonotic origin, in contrast to some alternative concepts, including the probability of a laboratory incident or leak. Our data exhibit that zoonotic origin (Z) has higher evidence-based support as compared to laboratory origin (L). Importantly, based on all the studies included, we generated the forest plot with 95% confidence intervals (CIs) of the risk ratio estimates. Our meta-analysis further supports the zoonotic origin of SARS/SARS-CoV-2 in the included studies.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Humanos , Pandemias
10.
Transbound Emerg Dis ; 69(5): e1899-e1912, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35306739

RESUMEN

Biosecurity measures have been introduced to limit economic losses and zoonotic exposures to humans by preventing and controlling animal diseases. However, they are implemented on individual farms with varying frequency. The goal of this study was to evaluate which biosecurity measures were used by farmers to prevent infectious diseases in ruminant livestock and to identify factors that influenced these decisions. We conducted a survey in 264 ruminant livestock farmers in a 40,000 km2 area in the Free State and Northern Cape provinces of South Africa. We used descriptive statistics, to characterize biosecurity measures and farm attributes, then multivariable binomial regression to assess the strength of the association between the attributes and the implementation of biosecurity measures including property fencing, separate equipment use on different species, separate rearing of species, isolation of sick animals, isolation of pregnant animals, quarantine of new animals, animal transport cleaning, vaccination, tick control and insect control. Ninety-nine percent of farmers reported using at least one of the 10 biosecurity measures investigated (median [M]: 6; range: 0-10). The most frequently used biosecurity measures were tick control (81%, 214 out of 264), vaccination (80%, 211 out of 264) and isolation of sick animals (72%, 190 out of 264). More biosecurity measures were used on farms with 65-282 animals (M: 6; odds ratio [OR]: 1.52) or farms with 283-12,030 animals (M: 7; OR: 1.87) than on farms with fewer than 65 animals (M: 4). Furthermore, farmers who kept two animal species (M: 7; OR: 1.41) or three or more species (M: 7) used more biosecurity measures than single-species operations (M: 4). Farmers with privately owned land used more biosecurity measures (M: 6; OR: 1.51) than those grazing their animals on communal land (M: 3.5). Farms that reported previous Rift Valley fever (RVF) outbreaks used more biosecurity measures (M: 7; OR: 1.25) compared with farms without RVF reports (M: 6) and those that purchased animals in the 12 months prior to the survey (M: 7; OR: 1.19) compared with those that did not (M: 6). When introducing new animals into their herds (n = 122), most farmers used fewer biosecurity measures than they did for their existing herd: 34% (41 out of 122) used multiple biosecurity measures like those of vaccination, tick control, quarantine or antibiotic use, whereas 36% (44 out of 122) used only one and 30% (37 out of 122) used none. Certain farm features, primarily those related to size and commercialization, were associated with more frequent use of biosecurity measures. Given the variation in the application of biosecurity measures, more awareness and technical assistance are needed to support the implementation of a biosecurity management plan appropriate for the type of farm operation and available resources.


Asunto(s)
Enfermedades Transmisibles , Fiebre del Valle del Rift , Crianza de Animales Domésticos , Animales , Antibacterianos , Bioaseguramiento , Enfermedades Transmisibles/veterinaria , Agricultores , Granjas , Humanos , Ganado , Rumiantes , Sudáfrica/epidemiología , Encuestas y Cuestionarios
11.
Pathogens ; 11(2)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35215069

RESUMEN

Rift Valley fever virus (RVFV) is a mosquito-borne, zoonotic phlebovirus-causing disease in domestic ruminants and humans in Africa, the Arabian Peninsula and some Indian Ocean islands. Outbreaks, characterized by abortion storms and a high morbidity rate in newborn animals, occur after heavy and prolonged rainfalls favouring the breeding of mosquitoes. However, the identity of the important mosquito vectors of RVFV is poorly known in most areas. Mosquitoes collected in the Ndumo area of tropical north-eastern KwaZulu-Natal (KZN), South Africa, were tested for RVFV nucleic acid using RT-PCR. The virus was detected in a single pool of unfed Aedes (Aedimorphus) durbanensis, indicating that this seasonally abundant mosquito species could serve as a vector in this area of endemic RVFV circulation. Phylogenetic analysis indicated the identified virus is closely related to two isolates from the earliest outbreaks, which occurred in central South Africa more than 60 years ago, indicating long-term endemicity in the region. Further research is required to understand the eco-epidemiology of RVFV and the vectors responsible for its circulation in the eastern tropical coastal region of southern Africa.

12.
J Med Virol ; 94(5): 2160-2166, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35050521

RESUMEN

The novel Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variant, Omicron (PANGO lineage B.1.1.529) is being reported from all around the world. The WHO has categorized Omicron as a Variant of Concern (VOC) considering its higher transmissibility and infectivity, vaccine breakthrough cases. As of January 6, 2022, Omicron has been reported in at least 149 countries. Therefore, this study was planned to investigate the transmission dynamics and mutational prevalence of the novel SARS-CoV-2 Omicron variant. The transmission dynamics and Omicron SARS-CoV-2 divergence was studied using GISAID and Nextstrain which provides information about the genetic sequences, epidemiological, geographical, and species-specific data of human, avian, and animal viruses. Further, the mutation prevalence in spike glycoprotein of Omicron was studied, and the frequency of the crucial mutations was compared with the other prevalent VOCs. The transmission dynamics suggest that the Omicron was first identified in South Africa and then it was reported in the United Kingdom followed by the United States and Australia. Further, our phylogenetic analysis suggests that Omicron (BA.1) was clustered distinctly from the other VOCs. In the Spike glycoprotein, the Omicron (B.1.1.529) demonstrates critical 32 amino acid changes. This study may help us to understand mutational hotspots, transmission dynamics, phylogenetic divergence, effect on testing and immunity, which shall promote the progress of the clinical application and basic research.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , COVID-19/epidemiología , Humanos , Mutación , Filogenia , Prevalencia , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
13.
J Med Virol ; 94(4): 1738-1744, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34905235

RESUMEN

As the latest identified novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern (VOC), the influence of Omicron on our globe grows promptly. Compared with the last VOC (Delta variant), more mutations were identified, which may address the characteristics of Omicron. Considering these crucial mutations and their implications including an increase in transmissibility, COVID-19 severity, and reduction of efficacy of currently available diagnostics, vaccines, and therapeutics, Omicron has been classified as one of the VOC. Notably, 15 of these mutations reside in the receptor-binding domain of spike glycoprotein, which may alter transmissibility, infectivity, neutralizing antibody escape, and vaccine breakthrough cases of COVID-19. Therefore, our present study characterizes the mutational hotspots of the Omicron variant in comparison with the Delta variant of SARS-CoV-2. Furthermore, detailed information was analyzed to characterize the global perspective of Omicron, including transmission dynamic, effect on testing, and immunity, which shall promote the progress of the clinical application and basic research. Collectively, our data suggest that due to continuous variation in the spike glycoprotein sequences, the use of coronavirus-specific attachment inhibitors may not be the current choice of therapy for emerging SARS-CoV-2 VOCs. Hence, we need to proceed with a sense of urgency in this matter.


Asunto(s)
SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/transmisión , Prueba de COVID-19 , Humanos , Evasión Inmune/genética , Mutación , Filogenia , Prevalencia , Unión Proteica/genética , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunación , Acoplamiento Viral
14.
Sci Rep ; 11(1): 24262, 2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34930962

RESUMEN

Bat-borne viruses in the Henipavirus genus have been associated with zoonotic diseases of high morbidity and mortality in Asia and Australia. In Africa, the Egyptian rousette bat species (Rousettus aegyptiacus) is an important viral host in which Henipavirus-related viral sequences have previously been identified. We expanded these findings by assessing the viral dynamics in a southern African bat population. A longitudinal study of henipavirus diversity and excretion dynamics identified 18 putative viral species circulating in a local population, three with differing seasonal dynamics, and the winter and spring periods posing a higher risk of virus spillover and transmission. The annual peaks in virus excretion are most likely driven by subadults and may be linked to the waning of maternal immunity and recolonization of the roost in early spring. These results provide insightful information into the bat-host relationship that can be extrapolated to other populations across Africa and be communicated to at-risk communities as a part of evidence-based public health education and prevention measures against pathogen spillover threats.


Asunto(s)
Quirópteros/virología , Reservorios de Enfermedades/virología , Marburgvirus/inmunología , Paramyxoviridae/inmunología , Estaciones del Año , África , Animales , Asia , Australia , Geografía , Henipavirus , Humanos , Estudios Longitudinales , Sudáfrica , Factores de Tiempo , Zoonosis/epidemiología , Zoonosis/virología
15.
Viruses ; 13(11)2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34835032

RESUMEN

This study aimed to determine the vector competence of bat-associated nycteribiid flies (Eucamsipoda africana) for Marburg virus (MARV) in the Egyptian Rousette Bat (ERB), Rousettus aegyptiacus. In flies fed on subcutaneously infected ERBs and tested from 3 to 43 days post infection (dpi), MARV was detected only in those that took blood during the peak of viremia, 5-7 dpi. Seroconversion did not occur in control bats in contact with MARV-infected bats infested with bat flies up to 43 days post exposure. In flies inoculated intra-coelomically with MARV and tested on days 0-29 post inoculation, only those assayed on day 0 and day 7 after inoculation were positive by q-RT-PCR, but the virus concentration was consistent with that of the inoculum. Bats remained MARV-seronegative up to 38 days after infestation and exposure to inoculated flies. The first filial generation pupae and flies collected at different times during the experiments were all negative by q-RT-PCR. Of 1693 nycteribiid flies collected from a wild ERB colony in Mahune Cave, South Africa where the enzootic transmission of MARV occurs, only one (0.06%) tested positive for the presence of MARV RNA. Our findings seem to demonstrate that bat flies do not play a significant role in the transmission and enzootic maintenance of MARV. However, ERBs eat nycteribiid flies; thus, the mechanical transmission of the virus through the exposure of damaged mucous membranes and/or skin to flies engorged with contaminated blood cannot be ruled out.


Asunto(s)
Quirópteros/virología , Dípteros/virología , Vectores de Enfermedades , Marburgvirus/aislamiento & purificación , Animales , Cuevas , Dípteros/fisiología , Infestaciones Ectoparasitarias/veterinaria , Sudáfrica
16.
Emerg Infect Dis ; 27(12): 3092-3102, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34808083

RESUMEN

We conducted a survey for group-specific indirect immunofluorescence antibody to mammarenaviruses by using Lassa fever and Mopeia virus antigens on serum specimens of 5,363 rodents of 33 species collected in South Africa and Zimbabwe during 1964-1994. Rodents were collected for unrelated purposes or for this study and stored at -70°C. We found antibody to be widely distributed in the 2 countries; antibody was detected in serum specimens of 1.2%-31.8% of 14 species of myomorph rodents, whereas 19 mammarenavirus isolates were obtained from serum specimens and viscera of 4 seropositive species. Phylogenetic analysis on the basis of partial nucleoprotein sequences indicates that 14 isolates from Mastomys natalensis, the Natal multimammate mouse, were Mopeia virus, whereas Merino Walk virus was characterized as a novel virus in a separate study. The remaining 4 isolates from 3 rodent species potentially constitute novel viruses pending full characterization.


Asunto(s)
Arenaviridae , Enfermedades de los Roedores , Animales , Reservorios de Enfermedades , Virus Lassa , Murinae , Filogenia , Sudáfrica/epidemiología , Zimbabwe/epidemiología
17.
Emerg Infect Dis ; 27(12): 3159-3162, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34808090

RESUMEN

We detected Rift Valley fever virus (RVFV) IgM and IgG in human serum samples collected during 2018-2019 in northern KwaZulu-Natal Province, South Africa. Our results show recent RVFV circulation and likely RVFV endemicity in this tropical coastal plain region of South Africa in the absence of apparent clinical disease.


Asunto(s)
Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Animales , Anticuerpos Antivirales , Humanos , Fiebre del Valle del Rift/epidemiología , Estudios Seroepidemiológicos , Sudáfrica/epidemiología
18.
Viruses ; 13(7)2021 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-34372574

RESUMEN

The mosquito-borne flavivirus, Kedougou virus (KEDV), first isolated in Senegal in 1972, is genetically related to dengue, Zika (ZIKV) and Spondweni viruses (SPOV). Serological surveillance studies in Senegal and isolation of KEDV in the Central African Republic indicate occurrence of KEDV infections in humans, but to date, no disease has been reported. Here, we assembled the coding-complete genome of a 1958 isolate of KEDV from a pool of Aedes circumluteolus mosquitoes collected in Ndumu, KwaZulu-Natal, South Africa. The AR1071 Ndumu KEDV isolate bears 80.51% pairwise nucleotide identity and 93.34% amino acid identity with the prototype DakAar-D1470 strain and was co-isolated with SPOV through intracerebral inoculation of suckling mice and passage on VeroE6 cells. This historical isolate expands the known geographic and temporal range of this relatively unknown flavivirus, aiding future temporal phylogenetic calibration and diagnostic assay refinement.


Asunto(s)
Infecciones por Flavivirus/epidemiología , Flavivirus/genética , Aedes/virología , Animales , Monitoreo Epidemiológico , Flavivirus/metabolismo , Flavivirus/patogenicidad , Infecciones por Flavivirus/genética , Historia del Siglo XX , Humanos , Mosquitos Vectores/virología , Filogenia , Sudáfrica/epidemiología , Enfermedades Transmitidas por Vectores/historia
19.
Animals (Basel) ; 11(8)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34438717

RESUMEN

Huculs (Equus caballus) are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal secretion swabs as a specimen source, isolation attempts were negative regarding ERAV, EHV-1, EAV, and EIV. According to the virus neutralisation method, in the sera obtained from the animals, antibodies against the following viruses were detected: EHV-1 in 12 horses (60%; with titres from 1:8 to 1:64), EIV A/H7N7 in 13 (65%; titres from 1:20 to 1:80), EIV A /H3N8 in 12 (60%; titres from 1:20 to 1:80), USUV in 5 (25%; titres from 1:10 to 1:80), and ERAV in 1 (5%; titre 1:32). Antibodies against EAV, EIAV, and WNV were not present in the tested sera. The detected presence of specific antibodies associated with five out of the eight equine viruses investigated indicates that the Hucul herd, due to its partial separation and lack of specific prophylaxis, could serve as a sentinel animal group for the detection of equine viruses/arboviruses present within the local ecosystem. The detection of common equine viral infections within the herd provides additional epidemiological data concerning the breed.

20.
Viruses ; 13(8)2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34452515

RESUMEN

Diagnostic performance of an indirect enzyme-linked immunosorbent assay (I-ELISA) based on a recombinant nucleocapsid protein (rNP) of the Rift Valley fever virus (RVFV) was validated for the detection of the IgG antibody in sheep (n = 3367), goat (n = 2632), and cattle (n = 3819) sera. Validation data sets were dichotomized according to the results of a virus neutralization test in sera obtained from RVF-endemic (Burkina Faso, Democratic Republic of Congo, Mozambique, Senegal, Uganda, and Yemen) and RVF-free countries (France, Poland, and the USA). Cut-off values were defined using the two-graph receiver operating characteristic analysis. Estimates of the diagnostic specificity of the RVFV rNP I-ELISA in animals from RVF-endemic countries ranged from 98.6% (cattle) to 99.5% (sheep) while in those originating from RVF-free countries, they ranged from 97.7% (sheep) to 98.1% (goats). Estimates of the diagnostic sensitivity in ruminants from RVF-endemic countries ranged from 90.7% (cattle) to 100% (goats). The results of this large-scale international validation study demonstrate the high diagnostic accuracy of the RVFV rNP I-ELISA. Standard incubation and inactivation procedures evaluated did not have an adverse effect on the detectable levels of the anti-RVFV IgG in ruminant sera and thus, together with recombinant antigen-based I-ELISA, provide a simple, safe, and robust diagnostic platform that can be automated and carried out outside expensive bio-containment facilities. These advantages are particularly important for less-resourced countries where there is a need to accelerate and improve RVF surveillance and research on epidemiology as well as to advance disease control measures.


Asunto(s)
Anticuerpos Antivirales/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina G/sangre , Fiebre del Valle del Rift/sangre , Virus de la Fiebre del Valle del Rift/inmunología , Animales , Bovinos/sangre , Cabras/sangre , Proteínas de la Nucleocápside/genética , Proteínas de la Nucleocápside/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Fiebre del Valle del Rift/diagnóstico , Fiebre del Valle del Rift/inmunología , Fiebre del Valle del Rift/virología , Virus de la Fiebre del Valle del Rift/genética , Virus de la Fiebre del Valle del Rift/aislamiento & purificación , Ovinos/sangre
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