Animal Virus Ecology and Evolution Are Shaped by the Virus Host-Body Infiltration and Colonization Pattern

The current classification of animal viruses is largely based on the virus molecular world. Less attention is given to why and how virus fitness results from the success of virus transmission. Virus transmission reflects the infection-shedding-transmission dynamics, and with it, the organ system involvement and other, macroscopic dimensions of the host environment. This study describes the transmission ecology of the world main livestock viruses, 36 in total, a mix of RNA, DNA and retroviruses. Following an iterative process, the viruses are virtually ranked in an outer- to inner-body fashion, by organ system, on ecological grounds. Also portrayed are the shifts in virus host tropism and virus genome. The synthesis of the findings reveals a predictive virus evolution framework, based on the outer- to inner-body changes in the interplay of host environment-transmission modes-organ system involvement-host cell infection cycle-virus genome. Outer-body viruses opportunistically respond to the variation in the external environment. For example, respiratory and enteric viruses tend to be associated with poultry and pig mass rearing. Ruminant and equine viruses tend to be more deep-rooted and host-specific, and also establish themselves in the vital inner-body systems. It is concluded that the framework may assist the study of new emerging viruses and pandemic risks.

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Animal virus ecology and evolution are shaped by the virus host-body infiltration and colonization pattern.

10.1101/492603 ◽

2018 ◽

Author(s):

Jan Slingenbergh

Keyword(s):

Virus Transmission ◽

Organ System ◽

Transmission Dynamics ◽

Cell Infection ◽

Virus Classification ◽

Host Environment ◽

Animal Virus ◽

Host Interactions ◽

System Involvement ◽

Virus Genomes

Abstract The current classification of animal viruses primarily relates to the virus molecular world, the genomic architecture and the corresponding host-cell infection cycle. This virus centered perspective does not make allowance for the precept that virus fitness hinges on the virus transmission success. Virus transmission reflects the infection-shedding-transmission dynamics and, with it, the organ system involvement and other, macroscopic dimensions of the host environment. This study examines the transmission ecology of the world main livestock viruses, 36 in total, belonging to eleven different families, and a mix of RNA, DNA and retroviruses. Viruses are virtually ranked in an outer- to inner-body fashion, based on the shifting organ system involvement and associated infection-shedding-transmission dynamics. As a next step, this ranking is disentangled with the aim to contrast two main host ecologies, poultry plus pig production and ruminant plus equine husbandry, as well as to create a distinction among the RNA, DNA and retroviruses, also ranked in an outer- to inner-body fashion. Spearman correlation reveals the matches among these various virus traits, as pertaining to the two host-ecologies, four infection-shedding-transmission related variables, and the three virus genomes. The collective results reveal the outer- to inner-body shifts in the interplay of host environment, virus-host interactions, and nature of the virus. Two opposing virus evolution pathways emerge, respectively for generalist type, outer-body and for specialist type, inner-body viruses. The ecological virus classification here presented is broadly consistent with the current virus classification system and offers the advantage of bringing substance and cohesion to the interrelationships among viruses and virus families.

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491. Aerosol-Generating Medical Procedures: Transmission of SARS-CoV-2 and Emerging Viruses

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.684 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S312-S312

Author(s):

Seth D Judson ◽

Vincent J Munster

Keyword(s):

High Risk ◽

Severe Disease ◽

Experimental Studies ◽

Virus Transmission ◽

Nosocomial Transmission ◽

Medical Procedures ◽

Emerging Viruses ◽

Zoonotic Viruses ◽

Increased Risk ◽

Hospital Acquired

Abstract Background During the pandemic of coronavirus disease 2019 (COVID-19), many questions arose regarding risks for hospital-acquired or nosocomial transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Aerosol generating medical procedures (AGMPs), techniques that can generate infectious, virus-laden aerosols, could potentially amplify transmission among healthcare workers (HCWs). Thus, it was widely recommended that HCWs use airborne precautions when performing AGMPs. However, in clinical settings it is often unclear what procedures constitute AGMPs and how the risk varies by procedure or pathogen. We set out to further define AGMPs and assess the risk for nosocomial transmission of SARS-CoV-2 and other high-risk viruses via AGMPs. Methods We identified potential AGMPs and emerging viruses that were high-risk for nosocomial transmission through reviewing experimental and clinical data. Potential AGMPs were those associated with previous virus transmission or mechanically capable of transmission. High-risk viruses were defined as those that cause severe disease in humans for which limited therapies or interventions exist, are infectious via aerosols in humans or non-human primates (NHPs), found in the respiratory tract of infected humans or NHPs, and had previous evidence of nosocomial transmission. Results We identified multiple potential AGMPs, which could be divided into those that generate aerosols or induce a patient to form aerosols, as well as eight families of high-risk viruses. All of the viruses were emerging zoonotic RNA viruses. In the family Coronaviridae, we identified potential evidence for SARS-CoV-1, MERS-CoV, and SARS-CoV-2 transmission via AGMPs. SARS-CoV-1 and SARS-CoV-2 were also found to be similarly stable when aerosolized. Conclusion Multiple emerging zoonotic viruses pose a high risk for nosocomial transmission through a variety of AGMPs. Given the similar stability of SARS-CoV-2 with SARS-CoV-1 when aerosolized and prior nosocomial transmission of SARS-CoV-1 via AGMPs, we suspect that certain AGMPs pose an increased risk for SARS-CoV-2 transmission. Additional experimental studies and on-site clinical sampling during AGMPs are necessary to further risk stratify AGMPs. Disclosures All Authors: No reported disclosures

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Natural rodent model of viral transmission reveals biological features of virus population dynamics

Journal of Experimental Medicine ◽

10.1084/jem.20211220 ◽

2021 ◽

Vol 219 (2) ◽

Author(s):

Elizabeth J. Fay ◽

Keir M. Balla ◽

Shanley N. Roach ◽

Frances K. Shepherd ◽

Dira S. Putri ◽

...

Keyword(s):

Virus Transmission ◽

Experimental Models ◽

Model System ◽

Host Factors ◽

Virus Population ◽

Laboratory Mice ◽

Emerging Viruses ◽

New Host ◽

New Members ◽

Biological Features

Emerging viruses threaten global health, but few experimental models can characterize the virus and host factors necessary for within- and cross-species transmission. Here, we leverage a model whereby pet store mice or rats—which harbor natural rodent pathogens—are cohoused with laboratory mice. This “dirty” mouse model offers a platform for studying acute transmission of viruses between and within hosts via natural mechanisms. We identified numerous viruses and other microbial species that transmit to cohoused mice, including prospective new members of the Coronaviridae, Astroviridae, Picornaviridae, and Narnaviridae families, and uncovered pathogen interactions that promote or prevent virus transmission. We also evaluated transmission dynamics of murine astroviruses during transmission and spread within a new host. Finally, by cohousing our laboratory mice with the bedding of pet store rats, we identified cross-species transmission of a rat astrovirus. Overall, this model system allows for the analysis of transmission of natural rodent viruses and is a platform to further characterize barriers to zoonosis.

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Clinical Characteristics and Organ System Involvement in Sarcoidosis: Comparison of the University of Minnesota Cohort and Other Cohorts

10.21203/rs.2.17789/v2 ◽

2020 ◽

Author(s):

Hok Sreng ◽

David M Perlman ◽

Chetan Shenoy ◽

Daniel J Steinberger ◽

Rebecca J Cogswell ◽

...

Keyword(s):

Clinical Characteristics ◽

High Variability ◽

Organ System ◽

Assessment Instrument ◽

Genomic Research ◽

Unknown Etiology ◽

University Of Minnesota ◽

System Involvement ◽

Tertiary Center ◽

The University

Abstract Background: Sarcoidosis is a systemic granulomatous disease of unknown etiology. Clinical cohort studies of different populations are important to understand the high variability in clinical presentation and disease course of sarcoidosis. The aim of the study is to evaluate clinical characteristics, including organ involvement, pulmonary function tests, and laboratory parameters, in a sarcoidosis cohort at the University of Minnesota. We compare the organ system involvement of this cohort with other available cohorts. Methods: We conducted a retrospective data collection and analysis of 187 subjects with biopsy-proven sarcoidosis seen at a tertiary center. Organ system involvement was determined using the WASOG sarcoidosis organ assessment instrument. Clinical phenotype groups were classified using the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis criteria. Results: Mean subject age at diagnosis was 45.8 ± 12.4, with a higher proportion of males (55.1%), and a higher proportion of blacks (17.1%) compared to the racial distribution of Minnesota residents (5.95%). The majority (71.1%) of subjects required anti-inflammatory therapy for at least 1 month. Compared to the A Case Control Etiologic Study of Sarcoidosis cohort, there was a higher frequency of extra-thoracic lymph node (34.2% vs. 15.2%), eye (20.9% vs. 11.8%), liver (17.6% vs. 11.5%), spleen (20.9% vs. 6.7%), musculoskeletal (9.6% vs. 0.5%), and cardiac (10.7% vs. 2.3%) involvement in our cohort. A multisystem disease with at least five different organs involved was identified in 13.4% of subjects. A restrictive physiological pattern was observed in 21.6% of subjects, followed by an obstructive pattern in 17.3% and mixed obstructive and restrictive pattern in 2.2%. Almost half (49.2%) were Scadding stages II/III. Commonly employed disease activity markers, including soluble interleukin-2 receptor and angiotensin-converting enzyme, did not differ between treated and untreated groups. Conclusions: This cohort features a relatively high frequency of high-risk sarcoidosis phenotypes including cardiac and multiorgan disease. Commonly-utilized serum biomarkers do not identify subpopulations that require or do better with treatment. Findings from this study present further the high-variability nature of sarcoidosis and the need for a more reliable biomarker to predict and measure disease severity and outcomes for better clinical management for sarcoidosis patients.

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