Jun 30, 2017
Yellow Fever and Dengue Fever Viruses' Serosurvey in Non-human Primates of the Kedougou Forest Galleries in Southeastern SenegalThe potential risk of non-human primates in Senegal to be natural hosts for arboviruses of importance for human has been assessed. A total of 58 wild monkeys, including 14 Erythrocebus patas and 44 Chlorocebus sabaeus, were trapped at three sites within forest galleries and the nearby village of Ngari, in the Kedougou area, Southeastern Senegal. ### Photo credit: publicdomainphotography via Visual hunt / CC BY-SA
Aug 19, 2016
Uncovering Earth’s ViromeViruses are the most abundant biological entities on Earth, but challenges in detecting, isolating, and classifying unknown viruses have prevented exhaustive surveys of the global virome. Here we analysed over 5 Tb of metagenomic sequence data from 3,042 geographically diverse samples to assess the global distribution, phylogenetic diversity, and host specificity of viruses. We discovered over 125,000 partial DNA viral genomes, including the largest phage yet identified, and increased the number of known viral genes by 16-fold. Half of the predicted partial viral genomes were clustered into genetically distinct groups, most of which included genes unrelated to those in known viruses. Using CRISPR spacers and transfer RNA matches to link viral groups to microbial host(s), we doubled the number of microbial phyla known to be infected by viruses, and identified viruses that can infect organisms from different phyla. Analysis of viral distribution across diverse ecosystems revealed strong habitat-type specificity for the vast majority of viruses, but also identified some cosmopolitan groups. Our results highlight an extensive global viral diversity and provide detailed insight into viral habitat distribution and host–virus interactions. doi:10.1038/nature1909
Aug 02, 2016
The Importance of Data in Salmonella Risk Mitigation: Development of a Cloud-based Technical Platform for Food Safety Management in Poultry ProductionFoodborne disease outbreaks represent an ever-present risk to human health and the poultry industry, with notable Salmonella outbreaks occurring in recent years. Outbreaks result in adverse health effects to the consumer, as well as negative brand impact and financial losses to companies. Following a multistate outbreak of Salmonella Heidelberg, a poultry producer worked with a biotechnology firm to collect, integrate, and analyze data across its operations.
Jun 17, 2016
Zika Virus in the Americas: Early Epidemiological and Genetic FindingsBrazil has experienced an unprecedented epidemic of Zika virus (ZIKV), with ~30,000 cases reported to date. ZIKV was first detected in Brazil in May 2015 and cases of microcephaly potentially associated with ZIKV infection were identified in November 2015. Using next generation sequencing we generated seven Brazilian ZIKV genomes, sampled from four self-limited cases, one blood donor, one fatal adult case, and one newborn with microcephaly and congenital malformations. Phylogenetic and molecular clock analyses show a single introduction of ZIKV into the Americas, estimated to have occurred between May-Dec 2013, more than 12 months prior to the detection of ZIKV in Brazil. The estimated date of origin coincides with an increase in air passengers to Brazil from ZIKV endemic areas, and with reported outbreaks in Pacific Islands. ZIKV genomes from Brazil are phylogenetically interspersed with those from other South American and Caribbean countries. Mapping mutations onto existing structural models revealed the context of viral amino acid changes present in the outbreak lineage; however no shared amino acid changes were found among the three currently available virus genomes from microcephaly cases. Municipality-level incidence data indicate that reports of suspected microcephaly in Brazil best correlate with ZIKV incidence around week 17 of pregnancy, although this does not demonstrate causation. Our genetic description and analysis of ZIKV isolates in Brazil provide a baseline for future studies of the evolution and molecular epidemiology in the Americas of this emerging virus.
Oct 01, 2015
The Vietnam Initiative on Zoonotic Infections (VIZIONS): A Strategic Approach to Studying Emerging Zoonotic Infectious DiseasesThe effect of newly emerging or re-emerging infectious diseases of zoonotic origin in human populations can be potentially catastrophic, and large-scale investigations of such diseases are highly challenging. The monitoring of emergence events is subject to ascertainment bias, whether at the level of species discovery, emerging disease events, or disease outbreaks in human populations. Disease surveillance is generally performed post hoc, driven by a response to recent events and by the availability of detection and identification technologies.
Jun 11, 2015
Chiropteran and Filoviruses in Africa: Unveiling an Ancient HistoryEbolavirus and Marburgvirus belong to the Filovirus family and are responsible for hemorrhagic fevers in Africa. The first documented Filovirus outbreak in Africa occurred in Central Africa and was attributed to Ebolavirus species. In the last four decades, Filoviral hemorrhagic fevers (FHFs) outbreaks caused by Ebola and Marburg viruses have been on the increase in Africa. The 2013-2015 outbreak has been the largest outbreak in human and has had the most devastating human and economic impact. Epidemics usually originate from a primary single introduction of the virus into simian or human population followed by an interspecies spill over.
Apr 20, 2015
Understanding the Emergence of Ebola Virus Disease in Sierra Leone: Stalking the Virus in the Threatening Wake of EmergenceSince Ebola Virus Disease (EVD) was first identified in 1976 in what is now the Democratic Republic of Congo, and despite the numerous outbreaks recorded to date, rarely has an epidemic origin been identified. Indeed, among the twenty-one most documented EVD outbreaks in Africa, an index case has been identified four times, and hypothesized in only two other instances. The initial steps of emergence and spread of a virus are critical in the development of a potential outbreak and need to be thoroughly dissected and understood in order to improve on preventative strategies. In the current West African outbreak of EVD, a unique index case has been identified, pinpointing the geographical origin of the epidemic in Guinea. Herein, we provide an accounting of events that serve as the footprint of EVD emergence in Sierra Leone and a road map for risk mitigation fueled by lessons learned.
Nov 24, 2014
Nomenclature-and Database-Compatible Names for the Two Ebola Virus Variants that Emerged in Guinea and the Democratic Republic of the Congo in 2014Abstract: In 2014, Ebola virus (EBOV) was identified as the etiological agent of a large and still expanding outbreak of Ebola virus disease (EVD) in West Africa and a much more confined EVD outbreak in Middle Africa. Epidemiological and evolutionary analyses confirmed that all cases of both outbreaks are connected to a single introduction each of EBOV into human populations and that both outbreaks are not directly connected. Coding-complete genomic sequence analyses of isolates revealed that the two outbreaks were caused by two novel EBOV variants, and initial clinical observations suggest that neither of them should be considered strains. Here we present consensus decisions on naming for both variants (West Africa: “Makona”, Middle Africa: “Lomela”) and provide database-compatible full, shortened, and abbreviated names that are in line with recently established filovirus sub-species nomenclatures. ### Photo credit: NIAID via VisualHunt.com / CC BY
Nov 23, 2014
Long-term Persistence of Chikungunya Virus Neutralizing Antibodies in Human Populations of North Eastern ThailandBackground: Chikungunya virus (CHIKV) outbreak recurrences in Thailand are unpredictable and separated by unexplained and often long silent epidemiological periods that can last for several years. These silent periods could be explained in part by the fact that infection with one CHIKV strain confers lasting natural immunity, even against other CHIKV strains. In this study we evaluated the persistence of CHIKV-specific neutralizing antibodies in the population of Chumpae District, Khon Kaen Province, nineteen years after a CHIKV outbreak occurred in the same area in 1991. ### Photo credit: AJC1 via Visualhunt / CC BY-NC
Nov 19, 2014