Full genome Nobecovirus sequences from Malagasy fruit bats define a unique evolutionary history for this coronavirus clade

Bats are natural reservoirs for both Alpha- and Betacoronaviruses and the hypothesized original hosts of five of seven known zoonotic coronaviruses. To date, the vast majority of bat coronavirus research has been concentrated in Asia, though coronaviruses are globally distributed; indeed, SARS-CoV and SARS-CoV-2-related Betacoronaviruses in the subgenus Sarbecovirus have been identified circulating in Rhinolophid bats in both Africa and Europe, despite the relative dearth of surveillance in these regions. As part of a long-term study examining the dynamics of potentially zoonotic viruses in three species of endemic Madagascar fruit bat (Pteropus rufus, Eidolon dupreanum, Rousettus madagascariensis), we carried out metagenomic Next Generation Sequencing (mNGS) on urine, throat, and fecal samples obtained from wild-caught individuals. We report detection of RNA derived from Betacoronavirus subgenus Nobecovirus in fecal samples from all three species and describe full genome sequences of novel Nobecoviruses in P. rufus and R. madagascariensis. Phylogenetic analysis indicates the existence of five distinct Nobecovirus clades, one of which is defined by the highly divergent sequence reported here from P. rufus bats. Madagascar Nobecoviruses derived from P. rufus and R. madagascariensis demonstrate, respectively, Asian and African phylogeographic origins, mirroring those of their fruit bat hosts. Bootscan recombination analysis indicates significant selection has taken place in the spike, nucleocapsid, and NS7 accessory protein regions of the genome for viruses derived from both bat hosts. Madagascar offers a unique phylogeographic nexus of bats and viruses with both Asian and African phylogeographic origins, providing opportunities for unprecedented mixing of viral groups and, potentially, recombination. As fruit bats are handled and consumed widely across Madagascar for subsistence, understanding the landscape of potentially zoonotic coronavirus circulation is essential for mitigation of future zoonotic threats.

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Attenuated infection by a Pteropine orthoreovirus isolated from an Egyptian fruit bat in Zambia

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009768 ◽

2021 ◽

Vol 15 (9) ◽

pp. e0009768

Author(s):

Hayato Harima ◽

Michihito Sasaki ◽

Yasuko Orba ◽

Kosuke Okuya ◽

Yongjin Qiu ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Phylogenetic Analyses ◽

Respiratory Illness ◽

Replication Capacity ◽

Fruit Bats ◽

Rt Pcr ◽

Fruit Bat ◽

Eidolon Helvum ◽

Severe Respiratory Illness ◽

Generation Sequencing

Background Pteropine orthoreovirus (PRV) is an emerging bat-borne zoonotic virus that causes severe respiratory illness in humans. Although PRVs have been identified in fruit bats and humans in Australia and Asia, little is known about the prevalence of PRV infection in Africa. Therefore, this study performed an PRV surveillance in fruit bats in Zambia. Methods Egyptian fruit bats (Rousettus aegyptiacus, n = 47) and straw-colored fruit bats (Eidolon helvum, n = 33) captured in Zambia in 2017–2018 were screened for PRV infection using RT-PCR and serum neutralization tests. The complete genome sequence of an isolated PRV strain was determined by next generation sequencing and subjected to BLAST and phylogenetic analyses. Replication capacity and pathogenicity of the strain were investigated using Vero E6 cell cultures and BALB/c mice, respectively. Results An PRV strain, tentatively named Nachunsulwe-57, was isolated from one Egyptian fruit bat. Serological assays demonstrated that 98% of sera (69/70) collected from Egyptian fruit bats (n = 37) and straw-colored fruit bats (n = 33) had neutralizing antibodies against PRV. Genetic analyses revealed that all 10 genome segments of Nachunsulwe-57 were closely related to a bat-derived Kasama strain found in Uganda. Nachunsulwe-57 showed less efficiency in viral growth and lower pathogenicity in mice than another PRV strain, Miyazaki-Bali/2007, isolated from a patient. Conclusions A high proportion of Egyptian fruit bats and straw-colored fruit bats were found to be seropositive to PRV in Zambia. Importantly, a new PRV strain (Nachunsulwe-57) was isolated from an Egyptian fruit bat in Zambia, which had relatively weak pathogenicity in mice. Taken together, our findings provide new epidemiological insights about PRV infection in bats and indicate the first isolation of an PRV strain that may have low pathogenicity to humans.

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Tissue folates in fruit bats (Rousettus aegyptiacus) with nitrous oxide-induced vitamin B12deficiency and neurological impairment

British Journal Of Nutrition ◽

10.1079/bjn19870116 ◽

1987 ◽

Vol 58 (3) ◽

pp. 485-491 ◽

Cited By ~ 2

Author(s):

Justin Van Der Westhuyzen ◽

Richard E. Davis ◽

Graham C. Icke ◽

Jack Metz

Keyword(s):

Nitrous Oxide ◽

Subcellular Distribution ◽

Neurological Impairment ◽

Fruit Bats ◽

Fruit Bat

1. Long-term exposure of the fruit bat Rousettus aegyptiacus to nitrous oxide, which inactivates methylco balamin, leads to neurological impairment and ataxia.2. In N2, O-exposed animals, liver concentrations of total folates and methyl folates decreased to less than one fifth that of control animals. Pediococcus cerevisiue-active folates were also reduced.3. In brain, there were no changes in total or methyl folates, but P.cerevisiae-active folates were lower in N2, O-exposed animals.4. Supplementation with methionine retarded the development of neurological impairment and the fall in liver total and methyl folates, but not that in P. cerevisiae-active folates.5. Supplementation with serine failed to retard the development of neurological impairment or fall in hepatic folates.6. The present results suggest that the N2O-induced neurological impairment in the bat is not related to depletion of cerebral folates, but do not exclude changes in the subcellular distribution of folates.

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Egyptian Fruit Bats (Rousettus aegyptiacus) Were Resistant to Experimental Inoculation with Avian-Origin Influenza A Virus of Subtype H9N2, But Are Susceptible to Experimental Infection with Bat-Borne H9N2 Virus

Viruses ◽

10.3390/v13040672 ◽

2021 ◽

Vol 13 (4) ◽

pp. 672

Author(s):

Nico Joel Halwe ◽

Marco Gorka ◽

Bernd Hoffmann ◽

Melanie Rissmann ◽

Angele Breithaupt ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

H9n2 Virus ◽

Productive Infection ◽

Fruit Bats ◽

Influenza A Viruses ◽

New Host ◽

H9n2 Subtype ◽

Fruit Bat ◽

Zoonotic Viruses

Influenza A viruses (IAV) of subtype H9N2, endemic in world-wide poultry holdings, are reported to cause spill-over infections to pigs and humans and have also contributed substantially to recent reassortment-derived pre-pandemic zoonotic viruses of concern, such as the Asian H7N9 viruses. Recently, a H9N2 bat influenza A virus was found in Egyptian fruit bats (Rousettus aegyptiacus), raising the question of whether this bat species is a suitable host for IAV. Here, we studied the susceptibility, pathogenesis and transmission of avian and bat-related H9N2 viruses in this new host. In a first experiment, we oronasally inoculated six Egyptian fruit bats with an avian-related H9N2 virus (A/layer chicken/Bangladesh/VP02-plaque/2016 (H9N2)). In a second experiment, six Egyptian fruit bats were inoculated with the newly discovered bat-related H9N2 virus (A/bat/Egypt/381OP/2017 (H9N2)). While R. aegyptiacus turned out to be refractory to an infection with H9N2 avian-type, inoculation with the bat H9N2 subtype established a productive infection in all inoculated animals with a detectable seroconversion at day 21 post-infection. In conclusion, Egyptian fruit bats are most likely not susceptible to the avian H9N2 subtype, but can be infected with fruit bat-derived H9N2. H9-specific sero-reactivities in fruit bats in the field are therefore more likely the result of contact with a bat-adapted H9N2 strain.

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