Ebola Virus Persistence Research Articles

Rapid outbreak sequencing of Ebola virus in Sierra Leone identifies transmission chains linked to sporadic cases.

To end the largest known outbreak of Ebola virus disease (EVD) in West Africa and to prevent new transmissions, rapid epidemiological tracing of cases and contacts was required. The ability to quickly identify unknown sources and chains of transmission is key to ending the EVD epidemic and of even greater importance in the context of recent reports of Ebola virus (EBOV) persistence in survivors. Phylogenetic analysis of complete EBOV genomes can provide important information on the source of any new infection. A local deep sequencing facility was established at the Mateneh Ebola Treatment Centre in central Sierra Leone. The facility included all wetlab and computational resources to rapidly process EBOV diagnostic samples into full genome sequences. We produced 554 EBOV genomes from EVD cases across Sierra Leone. These genomes provided a detailed description of EBOV evolution and facilitated phylogenetic tracking of new EVD cases. Importantly, we show that linked genomic and epidemiological data can not only support contact tracing but also identify unconventional transmission chains involving body fluids, including semen. Rapid EBOV genome sequencing, when linked to epidemiological information and a comprehensive database of virus sequences across the outbreak, provided a powerful tool for public health epidemic control efforts.

Studies of Ebola Virus persistence in the Body Fluids of a Patient at Advanced Stages of Convalescence

At present EVD epidemic, which claimed the lives of more than 10000 people, is still underway in West Africa Countries. Promptness and quality of laboratory diagnostics, alongside with delivered anti-epidemic measures predetermine efficacy of Ebola response operation. Due to a lack of means for the specific prophylaxis and treatment of the disease, asymptomatic patients are discharged from hospitals, based on criteria recommended by WHO, which might be insufficient. Viral RNA is detected in different clinical samples taken from the patients even at the advanced stages of convalescence, which requires essential investigation of peculiarities of Ebola persistence in various biological fluids. The article contains the data on the studies of biological samples, obtained from a female patient diagnosed with Ebola virus disease, applying various methods and techniques.

S04.3 What has ebola virus to do with sexually transmitted infections?

Ebola virus could play both direct and indirect roles in the epidemiology and control of sexually transmitted infections (STI). The world9s largest outbreak of Ebola virus had caused more than 23,000 cases and 11,000 deaths in Guinea, Liberia and Sierra Leone by the end of July 2015. Control efforts have largely interrupted transmission, but new endogenous cases have emerged in Liberia, which had been declared Ebola-free. And new cases continue to be reported in Guinea and Sierra Leone. First, the direct role of sexual transmission in sustaining Ebola virus transmission is intriguing but unknown. Sexual transmission of Ebola virus from a male survivor to a female partner in Liberia is strongly supported by epidemiological and genome sequencing data, but cannot be proven. Studies from earlier Ebola virus disease outbreaks have documented persistent viral shedding in semen and vaginal secretions. Ongoing research is examining the shedding, persistence and clearance of Ebola virus in genital fluids in more detail. Second, the Ebola virus disease outbreak has devastated the economy, diverted resources from already weak public health systems and disrupted social structures. Indirectly, the social and economic consequences of the epidemic are likely to have favoured the spread of known STI and HIV in the most heavily affected countries. This presentation will review the strengths and weaknesses of the evidence about Ebola virus as an STI and about the public health impact of the outbreak on STI and HIV control.

Persistence of Ebola Virus in Sterilized Wastewater.

In the wake of the ongoing 2014/2015 Ebola virus outbreak, significant questions regarding the appropriate handling of Ebola virus-contaminated liquid waste remain, including the persistence of Ebola virus in wastewater. To address these uncertainties, we evaluated the persistence of Ebola virus spiked in sterilized domestic sewage. The viral titer decreased approximately 99% within the first test day from an initial viral titer of 106 TCID50 mL–1; however, it could not be determined if this initial rapid decrease was due to aggregation or inactivation of the viral particles. The subsequent viral titer decrease was less rapid, and infectious Ebola virus particles persisted for all 8 days of the test. The inactivation constant (k) was determined to be −1.08 (2.1 days for a 90% viral titer decrease). Due to experimental conditions, we believe these results to be an upper bound for Ebola virus persistence in wastewater. Wastewater composition is inherently heterogeneous; subsequently, we caution that interpretation of these results should be made within a holistic assessment, including the effects of wastewater composition, dilution, and potential exposure routes within wastewater infrastructure. While it remains unknown if Ebola virus may be transmitted via wastewater, these data demonstrate a potential exposure route to infectious Ebola virus via wastewater and emphasize the value of a precautionary approach to wastewater handling in an epidemic response.

Persistence and transmission of the Ebola virus in wildlife

Infection with the Ebola virus can cause severe acute hemorrhagic fever in humans and nonhuman primates. The virus is highly virulent and there are no effective drug treatments or vaccines available to date. The largest recorded outbreak of Ebola virus disease (EVD) is currently ongoing; it has affected West Africa, which is outside of its previously reported and predicted niche. It was declared a Public Health Emergency of International Concern by the World Health Organization. Here, we reviewed studies on EVD and its associated etiology, ecology, and epidemiology, spanning approximately 40 years. Multi-disciplinary theoretical knowledge was integrated to explain the reasoning behind Ebola virus persistence, circulation, and spread, including knowledge relating to natural reservoir hosts and a detailed description of the role of bats and other wildlife in the spread of the Ebola virus. To prevent the spread of major pathogens from wild animals to humans, it is crucial to put forward the most effective measures of maintaining the security of social public health. It is essential to strengthen wildlife disease surveillance, establish a long-term, comprehensive surveillance system for early warning and prevention methods, and provide a scientific basis for better safeguarding of public health and safety.

Persistence of Ebola Virus in Ocular Fluid during Convalescence

Among the survivors of Ebola virus disease (EVD), complications that include uveitis can develop during convalescence, although the incidence and pathogenesis of EVD-associated uveitis are unknown. We describe a patient who recovered from EVD and was subsequently found to have severe unilateral uveitis during convalescence. Viable Zaire ebolavirus (EBOV) was detected in aqueous humor 14 weeks after the onset of EVD and 9 weeks after the clearance of viremia.

Comment on “Ebola Virus Persistence in the Environment: State of the Knowledge and Research Needs”

ADVERTISEMENT RETURN TO ISSUEPREVCorrespondenceNEXTComment on “Ebola Virus Persistence in the Environment: State of the Knowledge and Research Needs”Daniele S. Lantagne*† and Paul R. Hunter‡View Author Information† Department of Civil and Environmental Engineering, Tufts University, Medford, Massachusetts 02155, United States‡ Norwich Medical School, University of East Anglia, Norwich, Norfolk NR4 7TJ, United Kingdom*E-mail: [email protected]Cite this: Environ. Sci. Technol. Lett. 2015, 2, 2, 48–49Publication Date (Web):January 15, 2015Publication History Received29 December 2014Accepted15 January 2015Published online20 January 2015Published inissue 10 February 2015https://doi.org/10.1021/ez500410tCopyright © 2015 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views1216Altmetric-Citations5LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (173 KB) Get e-AlertsSUBJECTS:Antimicrobial activity,Chlorine,Liquids,Wastes Get e-Alerts

Response to Comment on “Ebola Virus Persistence in the Environment: State of the Knowledge and Research Needs”

Response to Comment on “Ebola Virus Persistence in the Environment: State of the Knowledge and Research Needs”

Ebola Virus Persistence in the Environment: State of the Knowledge and Research Needs

In March 2014, an outbreak of Ebola virus (Ebola) arose in western Africa. Since then, there have been more than 10000 cases reported with a mortality rate of approximately 70% in clinically confirmed cases. A significant unanswered question has arisen for the scientific and engineering communities, as well as the general public, surrounding Ebola virus persistence in the environment and the potential for an environmental route of Ebola virus exposure. Here, the authors review the state of knowledge of Ebola virus environmental persistence and highlight future research needs. In general, there are limited data on the environmental persistence or disinfection of Ebola virus available in the open literature. The available evidence suggests that Ebola virus is inactivated at a rate more rapid than or comparable to those of typically monitored enteric viruses. Additionally, while environmental exposure is not the dominant exposure route, available data suggest that it is imprudent to dismiss the potential of ...

Persistence and genetic stability of Ebola virus during the outbreak in Kikwit, Democratic Republic of the Congo, 1995.

Ebola virus persistence was examined in body fluids from 12 convalescent patients by virus isolation and reverse transcription-polymerase chain reaction (RT-PCR) during the 1995 Ebola hemorrhagic fever outbreak in Kikwit, Democratic Republic of the Congo. Virus RNA could be detected for up to 33 days in vaginal, rectal, and conjunctival swabs of 1 patient and up to 101 days in the seminal fluid of 4 patients. Infectious virus was detected in 1 seminal fluid sample obtained 82 days after disease onset. Sequence analysis of an RT-PCR fragment of the most variable region of the glycoprotein gene amplified from 9 patients revealed no nucleotide changes. The patient samples were selected so that they would include some from a suspected line of transmission with at least three human-to-human passages, some from 5 survivors and 4 deceased patients, and 2 from patients who provided multiple samples through convalescence. There was no evidence of different virus variants cocirculating during the outbreak or of genetic variation accumulating during human-to-human passage or during prolonged persistence in individual patients.