Isolation of Lagos bat virus from water mongoose.
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ABSTRACT:
SUBMITTER: Markotter W
PROVIDER: S-EPMC3291357 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well adapted to its natural host species and that populations of reservoir hosts in eastern and western Africa have sufficient interactions to share pathogens. High virus concentrations, in addition to being detected in the brain, were detected in the salivary glands and tongue and in an oral swab, suggesting that LBV is transmitted in the saliva. In other extraneural organs, the virus was generally associated with innervations and ganglia. The presence of infectious virus in the reproductive tract and in a vaginal swab implies an alternative opportunity for transmission. The isolate was pathogenic for laboratory mice by the intracerebral and intramuscular routes. Serologic screening demonstrated the presence of LBV-neutralizing antibodies in E. helvum and Rousettus aegyptiacus fruit bats. In different colonies the seroprevalence ranged from 40 to 67% and 29 to 46% for E. helvum and R. aegyptiacus, respectively. Nested reverse transcription-PCR did not reveal the presence of viral RNA in oral swabs of bats in the absence of brain infection. Several large bat roosts were identified in areas of dense human populations, raising public health concerns for the potential of lyssavirus infection.
| S-EPMC2292963 | biostudies-literature
Project description:Three more isolates of Lagos bat virus were recently recovered from fruit bats in South Africa after an apparent absence of this virus for 13 years. The sporadic occurrence of cases is likely due to inadequate surveillance programs for lyssavirus infections among bat populations in Africa.
| S-EPMC3291461 | biostudies-literature
Project description:Phylogenetic analyses suggest lyssaviruses, including Rabies virus, originated from bats. However, the role of bats in the maintenance, transmission and evolution of lyssaviruses is poorly understood. A number of genetically diverse lyssaviruses are present in Africa, including Lagos bat virus (LBV). A high seroprevalence of antibodies against LBV was detected in Eidolon helvum bats. Longitudinal seroprevalence and age-specific seroprevalence data were analysed and capture-mark-recapture (CMR) analysis used to follow 98 bats over 18 months. These data demonstrate endemic infection, with evidence of horizontal transmission, and force of infection was estimated for differing age categories. The CMR analysis found survival probabilities of seronegative and seropositive bats were not significantly different. The lack of increased mortality in seropositive animals suggests infection is not causing disease after extended incubation. These key findings point towards acute transmission of bat lyssaviruses in adapted bat hosts that occurs at a far higher rate than the occurrence of disease.
| S-EPMC9152339 | biostudies-literature
Project description:Lagos bat virus (LBV), one of the 17 accepted viral species of the Lyssavirus genus, was the first rabies-related virus described in 1956. This virus is endemic to the African continent and is rarely encountered. There are currently four lineages, although the observed genetic diversity exceeds existing lyssavirus species demarcation criteria. Several exposures to rabid bats infected with LBV have been reported; however, no known human cases have been reported to date. This review provides the history of LBV and summarizes previous knowledge as well as new detections. Genetic diversity, pathogenesis and prevention are re-evaluated and discussed.
| S-EPMC8067007 | biostudies-literature
Project description:Eidolon helvum bats are reservoir hosts for highly pathogenic lyssaviruses often showing limited disease upon natural infection. An enhanced antiviral interferon (IFN) response combined with reduced inflammation might be linked to the apparent virus tolerance in bats. Lyssavirus phosphoproteins inhibit the IFN response with virus strain-specific efficiency. To date, little is known regarding the lyssavirus P-dependent anti-IFN countermeasures in bats, mainly due to a lack of in vitro tools. By using E. helvum bat cell cultures in a newly established bat-specific IFN-promoter activation assay, we analyzed the IFN-ß inhibitory activity of multiple lyssavirus P in E. helvum compared to human cells. Initial virus infection studies with a recently isolated E. helvum-borne Lagos bat virus street strain from Ghana showed enhanced LBV propagation in an E. helvum lung cell line compared to human A549 lung cells at later time points suggesting effective viral countermeasures against cellular defense mechanisms. A direct comparison of the IFN-ß inhibitory activity of the LBV-GH P protein with other lyssavirus P proteins showed that LBV-GH P and RVP both strongly inhibited the bat IFN-β promotor activation (range 75-90%) in EidLu/20.2 and an E. helvum kidney cell line. Conversely, LBV-GH P blocked the activation of the human IFN-β promoter less efficiently compared to a prototypic Rabies virus P protein (range LBV P 52-68% vs RVP 71-95%) in two different human cell lines (HEK-293T, A549). The same pattern was seen for two prototypic LBV P variants suggesting an overall reduced LBV P IFN-ß inhibitory activity in human cells as compared to E. helvum bat cells. Increased IFN-ß inhibition by lyssavirus P in reservoir host cells might be a result of host-specific adaptation processes towards an enhanced IFN response in bat cells.
| S-EPMC8903296 | biostudies-literature
Project description:Rabies is a fatal neurologic disease caused by lyssavirus infection. People are infected through contact with infected animals. The relative increase of human rabies acquired from bats calls for a better understanding of lyssavirus infections in their natural hosts. So far, there is no experimental model that mimics natural lyssavirus infection in the reservoir bat species. Lagos bat virus is a lyssavirus that is endemic in straw-colored fruit bats (Eidolon helvum) in Africa. Here we compared the susceptibility of these bats to three strains of Lagos bat virus (from Senegal, Nigeria, and Ghana) by intracranial inoculation. To allow comparison between strains, we ensured the same titer of virus was inoculated in the same location of the brain of each bat. All bats (n = 3 per strain) were infected, and developed neurological signs, and fatal meningoencephalitis with lyssavirus antigen expression in neurons. There were three main differences among the groups. First, time to death was substantially shorter in the Senegal and Ghana groups (4 to 6 days) than in the Nigeria group (8 days). Second, each virus strain produced a distinct clinical syndrome. Third, the spread of virus to peripheral tissues, tested by hemi-nested reverse transcriptase PCR, was frequent (3 of 3 bats) and widespread (8 to 10 tissues positive of 11 tissues examined) in the Ghana group, was frequent and less widespread in the Senegal group (3/3 bats, 3 to 6 tissues positive), and was rare and restricted in the Nigeria group (1/3 bats, 2 tissues positive). Centrifugal spread of virus from brain to tissue of excretion in the oral cavity is required to enable lyssavirus transmission. Therefore, the Senegal and Ghana strains seem most suitable for further pathogenesis, and for transmission, studies in the straw-colored fruit bat.
| S-EPMC5854431 | biostudies-literature
Project description:Rabies is a fatal neurologic disease caused by lyssavirus infection. Bats are important natural reservoir hosts of various lyssaviruses that can be transmitted to people. The epidemiology and pathogenesis of rabies in bats are poorly understood, making it difficult to prevent zoonotic transmission. To further our understanding of lyssavirus pathogenesis in a natural bat host, an experimental model using straw-colored fruit bats (Eidolon helvum) and Lagos bat virus, an endemic lyssavirus in this species, was developed. To determine the lowest viral dose resulting in 100% productive infection, bats in five groups (four bats per group) were inoculated intramuscularly with one of five doses, ranging from 100.1 to 104.1 median tissue culture infectious dose (TCID50). More bats died due to the development of rabies after the middle dose (102.1 TCID50, 4/4 bats) than after lower (101.1, 2/4; 101.1, 2/4) or higher (103.1, 2/4; 104.1, 2/4) doses of virus. In the two highest dose groups, 4/8 bats developed rabies. Of those bats that remained healthy 3/4 bats seroconverted, suggesting that high antigen loads can trigger a strong immune response that abrogates a productive infection. In contrast, in the two lowest dose groups, 3/8 bats developed rabies, 1/8 remained healthy and seroconverted and 4/8 bats remained healthy and did not seroconvert, suggesting these doses are too low to reliably induce infection. The main lesion in all clinically affected bats was meningoencephalitis associated with lyssavirus-positive neurons. Lyssavirus antigen was detected in tongue epithelium (5/11 infected bats) rather than in salivary gland epithelium (0/11), suggesting viral excretion via the tongue. Thus, intramuscular inoculation of 102.1 TCID50 of Lagos bat virus into straw-colored fruit bats is a suitable model for lyssavirus associated bat rabies in a natural reservoir host, and can help with the investigation of lyssavirus infection dynamics in bats.
| S-EPMC7771871 | biostudies-literature
Project description:Background and objectivesBats are recognized as a major reservoir of lyssaviruses; however, no bat lyssavirus has been isolated in Asia except for Aravan and Khujand virus in Central Asia. All Chinese lyssavirus isolates in previous reports have been of species rabies virus, mainly from dogs. Following at least two recent bat-associated human rabies-like cases in northeast China, we have initiated a study of the prevalence of lyssaviruses in bats in Jilin province and their public health implications. A bat lyssavirus has been isolated and its pathogenicity in mice and genomic alignment have been determined.ResultsWe report the first isolation of a bat lyssavirus in China, from the brain of a northeastern bat, Murina leucogaster. Its nucleoprotein gene shared 92.4%/98.9% (nucleotide) and 92.2%/98.8% (amino acid) identity with the two known Irkut virus isolates from Russia, and was designated IRKV-THChina12. Following intracranial and intramuscular injection, IRKV-THChina12 produced rabies-like symptoms in adult mice with a short inoculation period and high mortality. Nucleotide sequence analysis showed that IRKV-THChina12 has the same genomic organization as other lyssaviruses and its isolation provides an independent origin for the species IRKV.ConclusionsWe have identified the existence of a bat lyssavirus in a common Chinese bat species. Its high pathogenicity in adult mice suggests that public warnings and medical education regarding bat bites in China should be increased, and that surveillance be extended to provide a better understanding of Irkut virus ecology and its significance for public health.
| S-EPMC3591329 | biostudies-literature
Project description:Lagos bat virus (LBV) is a phylogroup II lyssavirus exclusively found in Africa. Previous studies indicated that this virus is lethal to mice after intracranial and intramuscular inoculation. The antigenic composition of LBV differs substantially from that of rabies virus (RABV) and current rabies vaccines do not provide cross protection against phylogroup II lyssaviruses. To investigate the potential role of the LBV matrix protein (M) and glycoprotein (G) in pathogenesis, reverse genetics technology was used to construct recombinant viruses. The genes encoding the glycoprotein, or the matrix and glycoprotein of the attenuated RABV strain SPBN, were replaced with those of LBV resulting in SPBN-LBVG and SPBN-LBVM-LBVG, respectively. To evaluate the immunogenicity of the LBV G, the recombinant RABV SPBNGAS-LBVG-GAS was constructed with the LBV G inserted between two mutated RABV G genes (termed GAS). All the recombinant viruses were lethal to mice after intracranial (i.c.) inoculation although the pathogenicity of SPBNGAS-LBVG-GAS was lower compared to the other recombinant viruses. Following intramuscular (i.m.) inoculation, only SPBN-LBVM-LBVG was lethal to mice, indicating that both the M and G of LBV play a role in the pathogenesis. Most interestingly, serum collected from mice that were inoculated i.m. with SPBNGAS-LBVG-GAS neutralized phylogroup I and II lyssaviruses including RABV, Duvenhage virus (DUVV), LBV, and Mokola virus (MOKV), indicating that this recombinant virus has potential to be developed as a pan-lyssavirus vaccine.
| S-EPMC6082111 | biostudies-literature
Project description:Bat-borne viral diseases are a major public health concern among newly emerging infectious diseases which includes severe acute respiratory syndrome, Nipah, Marburg and Ebola virus disease. During the survey for Nipah virus among bats at North-East region of India; Tioman virus (TioV), a new member of the Paramyxoviridae family was isolated from tissues of Pteropus giganteus bats for the first time in India. This isolate was identified and confirmed by RT-PCR, sequence analysis and electron microscopy. A range of vertebrate cell lines were shown to be susceptible to Tioman virus. Negative electron microscopy study revealed the "herringbone" morphology of the nucleocapsid filaments and enveloped particles with distinct envelope projections a characteristic of the Paramyxoviridae family. Sequence analysis of Nucleocapsid gene of TioV demonstrated sequence identity of 99.87% and 99.99% nucleotide and amino acid respectively with of TioV strain isolated in Malaysia, 2001. This report demonstrates the first isolation of Tioman virus from a region where Nipah virus activity has been noticed in the past and recent years. Bat-borne viruses have become serious concern world-wide. A Survey of bats for novel viruses in this region would help in recognizing emerging viruses and combating diseases caused by them.
| S-EPMC7106170 | biostudies-literature