Browsing by Author "Crameri G"

Now showing 1 - 4 of 4
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    Continent-wide panmixia of an African fruit bat facilitates transmission of potentially zoonotic viruses
    (MacMillan Publishers Ltd., 2013) Peel AJ; Sargan DR; Baker KS; Hayman DTS; Barr JA; Crameri G; Suu-Ire R; Broder CC; Lembo T; Wang L-F; Fooks AR; Rossiter SJ; Wood JLN; Cunningam AA
    The straw-coloured fruit bat, Eidolon helvum, is Africa’s most widely distributed and commonly hunted fruit bat, often living in close proximity to human populations. This species has been identified as a reservoir of potentially zoonotic viruses, but uncertainties remain regarding viral transmission dynamics and mechanisms of persistence. Here we combine genetic and serological analyses of populations across Africa, to determine the extent of epidemiological connectivity among E. helvum populations. Multiple markers reveal panmixia across the continental range, at a greater geographical scale than previously recorded for any other mammal, whereas populations on remote islands were genetically distinct. Multiple serological assays reveal antibodies to henipaviruses and Lagos bat virus in all locations, including small isolated island populations, indicating that factors other than population size and connectivity may be responsible for viral persistence. Our findings have potentially important public health implications, and highlight a need to avoid disturbances that may precipitate viral spillover.
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    Henipavirus neutralising antibodies in an isolated island population of African fruit bats
    (Public Library of Science, 2012) Peel AJ; Baker KS; Crameri G; Barr JA; Hayman DTS; Wright E; Broder CC; Fernández-Loras A; Fooks AR; Wang L-F; Cunningham AA; Wood JLN
    Isolated islands provide valuable opportunities to study the persistence of viruses in wildlife populations, including population size thresholds such as the critical community size. The straw-coloured fruit bat, Eidolon helvum, has been identified as a reservoir for henipaviruses (serological evidence) and Lagos bat virus (LBV; virus isolation and serological evidence) in continental Africa. Here, we sampled from a remote population of E. helvum annobonensis fruit bats on Annobón island in the Gulf of Guinea to investigate whether antibodies to these viruses also exist in this isolated subspecies. Henipavirus serological analyses (Luminex multiplexed binding and inhibition assays, virus neutralisation tests and western blots) and lyssavirus serological analyses (LBV: modified Fluorescent Antibody Virus Neutralisation test, LBV and Mokola virus: lentivirus pseudovirus neutralisation assay) were undertaken on 73 and 70 samples respectively. Given the isolation of fruit bats on Annobón and their lack of connectivity with other populations, it was expected that the population size on the island would be too small to allow persistence of viruses that are thought to cause acute and immunising infections. However, the presence of antibodies against henipaviruses was detected using the Luminex binding assay and confirmed using alternative assays. Neutralising antibodies to LBV were detected in one bat using both assays. We demonstrate clear evidence for exposure of multiple individuals to henipaviruses in this remote population of E. helvum annobonensis fruit bats on Annobón island. The situation is less clear for LBV. Seroprevalences to henipaviruses and LBV in Annobón are notably different to those in E. helvum in continental locations studied using the same sampling techniques and assays. Whilst cross-sectional serological studies in wildlife populations cannot provide details on viral dynamics within populations, valuable information on the presence or absence of viruses may be obtained and utilised for informing future studie
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    Novel, potentially zoonotic paramyxoviruses from the African straw-colored fruit bat Eidolon helvum
    (American Society for Microbiology, 2013) Baker KS; Todd S; Marsh GA; Crameri G; Barr J; Kamins AO; Peel AJ; Yu M; Hayman DTS; Nadjm B; Mtove G; Amos B; Reyburn H; Nyarko E; Suu-Ire R; Murcia PR; Cunningham AA; Wood JLN; Wang L-F
    Bats carry a variety of paramyxoviruses that impact human and domestic animal health when spillover occurs. Recent studies have shown a great diversity of paramyxoviruses in an urban-roosting population of straw-colored fruit bats in Ghana. Here, we investigate this further through virus isolation and describe two novel rubulaviruses: Achimota virus 1 (AchPV1) and Achimota virus 2 (AchPV2). The viruses form a phylogenetic cluster with each other and other bat-derived rubulaviruses, such as Tuhoko viruses, Menangle virus, and Tioman virus. We developed AchPV1- and AchPV2-specific serological assays and found evidence of infection with both viruses in Eidolon helvum across sub-Saharan Africa and on islands in the Gulf of Guinea. Longitudinal sampling of E. helvum indicates virus persistence within fruit bat populations and suggests spread of AchPVs via horizontal transmission. We also detected possible serological evidence of human infection with AchPV2 in Ghana and Tanzania. It is likely that clinically significant zoonotic spillover of chiropteran paramyxoviruses could be missed throughout much of Africa where health surveillance and diagnostics are poor and comorbidities, such as infection with HIV or Plasmodium sp., are common.
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    The equine Hendra virus vaccine remains a highly effective preventative measure against infection in horses and humans: 'The imperative to develop a human vaccine for the Hendra virus in Australia'.
    (2016) Peel AJ; Field HE; Reid PA; Plowright RK; Broder CC; Skerratt LF; Hayman DTS; Restif O; Taylor M; Martin G; Crameri G; Smith I; Baker M; Marsh GA; Barr J; Breed AC; Wood JLN; Dhand N; Toribio J-A; Cunningham AA; Fulton I; Bryden WL; Secombe C; Wang L-F