238 research outputs found

    Effects of an Invasive Plant, Chinese Tallow (Triadica sebifera), on Development and Survival of Anuran Larvae

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    Amphibians are considered one of the most threatened vertebrate groups. Although numerous studies have addressed the many causes of amphibian population decline, little is known about effects of invasive plants. Chinese tallow (Triadica sebifera) is an exotic deciduous tree that has invaded the southeastern United States. Amphibian larvae in environments invaded by T. sebifera may be impacted negatively as autumn leaf litter decomposes in natal areas. We compared effects of leaf litter decomposition from T. sebifera and two native tree species on survival and development of four species of anuran larvae from eastern Texas. Larvae from Pseudacris fouquettei, Lithobates (Rana) sphenocephalus, Hyla versicolor, and Incilius (Bufo) nebulifer were introduced into mesocosms containing leaf litter from one of the three tree species. Pseudacris fouquettei and L. sphenocephalus, species that breed earlier in the year, had lower survival within the T. sebifera pools. Pseudacris fouquettei were smaller in T. sebifera mesocosms compared with native tree mesocosms, whereas L. sphenocephalus were larger in T. sebifera mesocosms. Hyla versicolor showed significant developmental and morphological differences in T. sebifera mesocosms; however, survival was not significantly different among treatments. Leaf litter treatment did not affect survival or development in I. nebulifer. Our results suggest that breeding season may determine how each species survives and develops in an environment with T. sebifera leaf litter. Triadica sebifera leaf litter breaks down faster than native species; therefore, negative effects may be short lived but pose a greater threat to species that breed soon after leaffall

    Infectious diseases epidemic threats and mass gatherings: refocusing global attention on the continuing spread of the Middle East Respiratory syndrome coronavirus (MERS-CoV).

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    Media and World Health Organization (WHO) attention on Zika virus transmission at the 2016 Rio Olympic Games and the 2015 Ebola virus outbreak in West Africa diverted the attention of global public health authorities from other lethal infectious diseases with epidemic potential. Mass gatherings such as the annual Hajj pilgrimage hosted by Kingdom of Saudi Arabia attract huge crowds from all continents, creating high-risk conditions for the rapid global spread of infectious diseases. The highly lethal Middle Eastern respiratory syndrome coronavirus (MERS-CoV) remains in the WHO list of top emerging diseases likely to cause major epidemics. The 2015 MERS-CoV outbreak in South Korea, in which 184 MERS cases including 33 deaths occurred in 2 months, that was imported from the Middle East by a South Korean businessman was a wake-up call for the global community to refocus attention on MERS-CoV and other emerging and re-emerging infectious diseases with epidemic potential. The international donor community and Middle Eastern countries should make available resources for, and make a serious commitment to, taking forward a "One Health" global network for proactive surveillance, rapid detection, and prevention of MERS-CoV and other epidemic infectious diseases threats

    Evolution of increased positive charge on the SARS-CoV-2 spike protein may be adaptation to human transmission

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    The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve and infect individuals. The exterior surface of the SARS-CoV-2 virion is dominated by the spike protein, and the current work examined spike protein biochemical features that have changed during the 3 years in which SARS-CoV-2 has infected humans. Our analysis identified a striking change in spike protein charge, from −8.3 in the original Lineage A and B viruses to −1.26 in most of the current Omicron viruses. We conclude that in addition to immune selection pressure, the evolution of SARS-CoV-2 has also altered viral spike protein biochemical properties, which may influence virion survival and promote transmission. Future vaccine and therapeutic development should also exploit and target these biochemical properties

    Zika virus outbreak and the case for building effective and sustainable rapid diagnostics laboratory capacity globally

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    New and re-emerging pathogens with epidemic potential have threatened global health security for the past century.1 As with the recent Ebola Virus Disease (EVD) epidemic, the Zika Virus (ZIKV) outbreak has yet again surprised and overwhelmed the international health community with an unexpected event for which it might have been better prepared

    Infectious diseases epidemic threats and mass gatherings: Refocusing global attention on the continuing spread of the Middle East Respiratory syndrome coronavirus (MERS-CoV)

    Get PDF
    Media and World Health Organization (WHO) attention on Zika virus transmission at the 2016 Rio Olympic Games and the 2015 Ebola virus outbreak in West Africa diverted the attention of global public health authorities from other lethal infectious diseases with epidemic potential. Mass gatherings such as the annual Hajj pilgrimage hosted by Kingdom of Saudi Arabia attract huge crowds from all continents, creating high-risk conditions for the rapid global spread of infectious diseases. The highly lethal Middle Eastern respiratory syndrome coronavirus (MERS-CoV) remains in the WHO list of top emerging diseases likely to cause major epidemics. The 2015 MERS-CoV outbreak in South Korea, in which 184 MERS cases including 33 deaths occurred in 2 months, that was imported from the Middle East by a South Korean businessman was a wake-up call for the global community to refocus attention on MERS-CoV and other emerging and re-emerging infectious diseases with epidemic potential. The international donor community and Middle Eastern countries should make available resources for, and make a serious commitment to, taking forward a "One Health" global network for proactive surveillance, rapid detection, and prevention of MERS-CoV and other epidemic infectious diseases threats

    Characterization of Norovirus and Other Human Enteric Viruses in Sewage and Stool Samples Through Next-Generation Sequencing.

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    This study aimed to optimize a method to identify human enteric viruses in sewage and stool samples using random primed next-generation sequencing. We tested three methods, two employed virus enrichment based on the binding properties of the viral capsid using pig-mucin capture or by selecting viral RNA prior to library preparation through a capture using the SureSelect target enrichment. The third method was based on a non-specific biophysical precipitation with polyethylene glycol. Full genomes of a number of common human enteric viruses including norovirus, rotavirus, husavirus, enterovirus and astrovirus were obtained. In stool samples full norovirus genome were detected as well as partial enterovirus genome. A variety of norovirus sequences was detected in sewage samples, with genogroup II being more prevalent. Interestingly, the pig-mucin capture enhanced not only the recovery of norovirus and rotavirus but also recovery of astrovirus, sapovirus and husavirus. Documenting sewage virome using these methods provides information for molecular epidemiology and may be useful in developing strategies to prevent further spread of viruses

    Unique protein features of SARS-CoV-2 relative to other Sarbecoviruses

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    Defining the unique properties of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein sequences has potential to explain the range of Coronavirus Disease 2019 severity. To achieve this we compared proteins encoded by all Sarbecoviruses using profile Hidden Markov Model similarities to identify protein features unique to SARS-CoV-2. Consistent with previous reports, a small set of bat- and pangolin-derived Sarbecoviruses show the greatest similarity to SARS-CoV-2 but are unlikely to be the direct source of SARS-CoV-2. Three proteins (nsp3, spike, and orf9) showed regions differing between the bat Sarbecoviruses and SARS-CoV-2 and indicate virus protein features that might have evolved to support human infection and/or transmission. Spike analysis identified all regions of the protein that have tolerated change and revealed that the current SARS-CoV-2 variants of concern have sampled only a fraction (∼31 per cent) of the possible spike domain changes which have occurred historically in Sarbecovirus evolution. This result emphasises the evolvability of these coronaviruses and the potential for further change in virus replication and transmission properties over the coming years

    Identification and characterization of Coronaviridae genomes from Vietnamese bats and rats based on conserved protein domains.

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    The Coronaviridae family of viruses encompasses a group of pathogens with a zoonotic potential as observed from previous outbreaks of the severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus. Accordingly, it seems important to identify and document the coronaviruses in animal reservoirs, many of which are uncharacterized and potentially missed by more standard diagnostic assays. A combination of sensitive deep sequencing technology and computational algorithms is essential for virus surveillance, especially for characterizing novel- or distantly related virus strains. Here, we explore the use of profile Hidden Markov Model-defined Pfam protein domains (Pfam domains) encoded by new sequences as a Coronaviridae sequence classification tool. The encoded domains are used first in a triage to identify potential Coronaviridae sequences and then processed using a Random Forest method to classify the sequences to the Coronaviridae genus level. The application of this algorithm on Coronaviridae genomes assembled from agnostic deep sequencing data from surveillance of bats and rats in Dong Thap province (Vietnam) identified thirty-four Alphacoronavirus and eleven Betacoronavirus genomes. This collection of bat and rat coronaviruses genomes provided essential information on the local diversity of coronaviruses and substantially expanded the number of coronavirus full genomes available from bat and rats and may facilitate further molecular studies on this group of viruses

    Complete Genome Characterization of Eight Human Parainfluenza Viruses from the Netherlands.

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    We report the complete genome sequences of eight human parainfluenza viruses (HPIV) belonging to Human respirovirus 1 (HPIV-1), Human respirovirus 3 (HPIV-3), Human rubulavirus 2 (HPIV-2), and Human rubulavirus 4 (HPIV-4). The genome sequences were generated using random-primed next-generation sequencing and represent the first HPIV full-genome sequences from the Netherlands
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