scholarly journals The Current Host Range of Hepatitis E Viruses

Viruses ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 452 ◽  
Author(s):  
Scott P Kenney
Keyword(s):  
Host Range ◽  
Human Health ◽  
Animal Species ◽  
Meat Products ◽  
Hepatitis E ◽  
Oral Route ◽  
Broad Host Range ◽  
Industrialized Countries ◽  
Primary Host ◽  
Human Specific

Hepatitis E virus (HEV) is an emerging zoonotic pathogen transmitting both human to human via the fecal oral route and from animals to humans through feces, direct contact, and consumption of contaminated meat products. Understanding the host range of the virus is critical for determining where potential threats to human health may be emerging from and where potential reservoirs for viral persistence in the environment may be hiding. Initially thought to be a human specific disease endemic to developing countries, the identification of swine as a primary host for genotypes 3 and 4 HEV in industrialized countries has begun a long journey of discovering novel strains of HEV and their animal hosts. As we continue identifying new strains of HEV in disparate animal species, it is becoming abundantly clear that HEV has a broad host range and many of these HEV strains can cross between differing animal species. These cross-species transmitting strains pose many unique challenges to human health as they are often unrecognized as sources of viral transmission.

Hepatitis E virus

2011 ◽  
Author(s):  
X. J. Meng
Keyword(s):  
Hepatitis E Virus ◽  
Animal Species ◽  
Rna Virus ◽  
Hepatitis E ◽  
Open Reading Frames ◽  
Industrialized Countries ◽  
Efficient Cell Culture System ◽  
The Family ◽  
Avian Hev ◽  
Animal Strains

Hepatitis E virus (HEV) is a small, non-enveloped, single-strand, positive-sense RNA virus of approximately 7.2 kb in size. HEV is classified in the family Hepeviridae consisting of four recognized major genotypes that infect humans and other animals. Genotypes 1 and 2 HEV are restricted to humans and often associated with large outbreaks and epidemics in developing countries with poor sanitation conditions, whereas genotypes 3 and 4 HEV infect humans, pigs and other animal species and are responsible for sporadic cases of hepatitis E in both developing and industrialized countries. The avian HEV associated with Hepatitis-Splenomegaly syndrome in chickens is genetically and antigenically related to mammalian HEV, and likely represents a new genus in the family. There exist three open reading frames in HEV genome: ORF1 encodes non-structural proteins, ORF2 encodes the capsid protein, and the ORF3 encodes a small phosphoprotein. ORF2 and ORF3 are translated from a single bicistronic mRNA, and overlap each other but neither overlaps ORF1. Due to the lack of an efficient cell culture system and a practical animal model for HEV, the mechanisms of HEV replication and pathogenesis are poorly understood. The recent identification and characterization of animal strains of HEV from pigs and chickens and the demonstrated ability of cross-species infection by these animal strains raise potential public health concerns for zoonotic HEV transmission. It has been shown that the genotypes 3 and 4 HEV strains from pigs can infect humans, and vice versa. Accumulating evidence indicated that hepatitis E is a zoonotic disease, and swine and perhaps other animal species are reservoirs for HEV. A vaccine against HEV is not yet available.

scholarly journals Mechanism of Cross-Species Transmission, Adaptive Evolution and Pathogenesis of Hepatitis E Virus

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 909
Author(s):  
Putu Prathiwi Primadharsini ◽  
Shigeo Nagashima ◽  
Hiroaki Okamoto
Keyword(s):  
Adaptive Evolution ◽  
Hepatitis E Virus ◽  
Current Knowledge ◽  
Hepatitis E ◽  
Oral Route ◽  
Open Reading Frames ◽  
Industrialized Countries ◽  
Zoonotic Infection ◽  
Host Determinants ◽  
Viral Determinants

Hepatitis E virus (HEV) is the leading cause of acute hepatitis worldwide. While the transmission in developing countries is dominated by fecal-oral route via drinking contaminated water, the zoonotic transmission is the major route of HEV infection in industrialized countries. The discovery of new HEV strains in a growing number of animal species poses a risk to zoonotic infection. However, the exact mechanism and the determinant factors of zoonotic infection are not completely understood. This review will discuss the current knowledge on the mechanism of cross-species transmission of HEV infection, including viral determinants, such as the open reading frames (ORFs), codon usage and adaptive evolution, as well as host determinants, such as host cellular factors and the host immune status, which possibly play pivotal roles during this event. The pathogenesis of hepatitis E infection will be briefly discussed, including the special forms of this disease, including extrahepatic manifestations, chronic infection, and fulminant hepatitis in pregnant women.

scholarly journals Bacteriophages as Preservation Agents to Promote Minimally Processed Food Safety

2020 ◽  
Vol 10 (4) ◽  
Author(s):  
Sihem Jebri
Keyword(s):  
Food Safety ◽  
Host Range ◽  
Human Health ◽  
Foodborne Pathogens ◽  
Fruits And Vegetables ◽  
Broad Host Range ◽  
Foodborne Disease ◽  
Processed Food ◽  
Minimally Processed ◽  
Global Concern

Foodborne disease related to ready to eat products contaminated by foodborne pathogens is a global concern due to its impact on human health and economy worldwide. Minimally processed food like ready to eat fruits and vegetables are not subjected to common preservation processes, additionally, the use of antibiotics and chemicals for pathogens eradication may affect consumers health. Baceriophages or viruses that infect bacteria have been suggested as bio-control tools and advantageous bio-preservation agents to promote minimally processed food safety. Recent studies show a reduction of pathogens after application of phages cocktails on fresh produce. Usefulness of broad-host range bacteriophages as bio-preservation agents needs more investigation.

scholarly journals Genetic Diversity of Hepatitis E Virus Type 3 in Switzerland—From Stable to Table

Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3177
Author(s):  
Isabelle Vonlanthen-Specker ◽  
Roger Stephan ◽  
Xaver Sidler ◽  
Dominik Moor ◽  
Cornel Fraefel ◽  
...  
Keyword(s):  
Meat Products ◽  
Hepatitis E ◽  
Health Concern ◽  
Industrialized Countries ◽  
Genotype 3 ◽  
Major Health ◽  
Wild Boars ◽  
Type 3 ◽  
Reservoir Hosts ◽  
Specific Cluster

Hepatitis E caused by hepatitis E viruses of the genotype 3 (HEV-3) is a major health concern in industrialized countries and due to its zoonotic character requires a “One Health” approach to unravel routes and sources of transmission. Knowing the viral diversity present in reservoir hosts, i.e., pigs but also wild boars, is an important prerequisite for molecular epidemiology. The aim of this study was to gain primary information on the diversity of HEV-3 subtypes present along the food chain in Switzerland, as well as the diversity within these subtypes. To this end, samples of domestic pigs from slaughterhouses and carcass collection points, as well as from hunted wild boars, were tested for HEV RNA and antibodies. HEV positive meat products were provided by food testing labs. The HEV subtypes were determined using Sanger and next generation sequencing. The genetic analyses confirmed the predominance of a Swiss-specific cluster within subtype HEV-3h in pigs, meat products, and wild boars. This cluster, which may result from local virus evolution due to the isolated Swiss pig industry, supports fast differentiation of domestic and imported infections with HEV.

Host plant acceptance in a generalist insect: threshold, feedback or choice?

Behaviour ◽  
2020 ◽  
Vol 157 (12-13) ◽  
pp. 1059-1089 ◽  
Author(s):  
Lachlan C. Jones ◽  
Michelle A. Rafter ◽  
Gimme H. Walter
Keyword(s):  
Host Range ◽  
Host Species ◽  
Feedback Loop ◽  
Egg Laying ◽  
Broad Host Range ◽  
Insect Herbivores ◽  
Primary Host ◽  
Measured Time ◽  
Plant Acceptance ◽  
Generalist Insect

Abstract Generalist insect herbivores feed mainly on one or more primary host species, but unlike specialists they also accept numerous secondary hosts. This raises the question of how generalists retain a broad host range yet allocate most of their eggs to primary hosts. We considered three possible explanations. (1) Threshold: secondary hosts are accepted less readily than primary hosts. (2) Feedback loop: insects ovipositing on primary hosts lay subsequent eggs faster than on secondary hosts. (3) Choice: insects compare plant cues sensed over a certain period and oviposit on preferred plants. We measured time and number of landings leading to egg-laying in a generalist moth, Helicoverpa punctigera, on a primary host and two secondary hosts and recorded subsequent egg-laying rates on each. The moths typically accepted only the primary host on the first landing and laid subsequent eggs on this host earlier in the night, indicating thresholds and feedback operate together.

A Review of Hepatitis E Virus†

2001 ◽  
Vol 64 (4) ◽  
pp. 572-586 ◽  
Author(s):  
JAMES L. SMITH
Keyword(s):  
Death Rate ◽  
Hepatitis E Virus ◽  
Swine Manure ◽  
Hepatitis E ◽  
The United States ◽  
Disease Diagnosis ◽  
Oral Route ◽  
Premature Delivery ◽  
Industrialized Countries ◽  
Human Virus

Hepatitis E virus (HEV) is a major cause of outbreaks and sporadic cases of viral hepatitis in tropical and subtropical countries but is infrequent in industrialized countries. The virus is transmitted by the fecal-oral route with fecally contaminated drinking water being the usual vehicle. Hepatitis resulting from HEV infection is a moderately severe jaundice that is self-limiting in most patients. Young adults, 15 to 30 years of age, are the main targets of infection, and the overall death rate is 0.5 to 3.0%. However, the death rate during pregnancy approaches 15 to 25%. Death of the mother and fetus, abortion, premature delivery, or death of a live-born baby soon after birth are common complications of hepatitis E infection during pregnancy. Hepatitis E virus is found in both wild and domestic animals; thus, HEV is a zoonotic virus. The viruses isolated from swine in the United States or Taiwan are closely related to human HEV found in those areas. The close genetic relationship of the swine and human virus suggests that swine may be a reservoir of HEV. In areas where swine are raised, swine manure could be a source of HEV contamination of irrigation water or coastal waters with concomitant contamination of produce or shellfish. Increasing globalization of food markets by industrialized countries has the potential of introducing HEV into new areas of the world. The purpose of this review is to cover certain aspects of hepatitis E including the causative agent, the disease, diagnosis, viral detection, viral transmission, epidemiology, populations targeted by HEV, and the role of animals as potential vectors of the virus.

scholarly journals 1615. Isolation of Lytic Bacteriophages with Broad Host Range Activity Against Pseudomonas aeruginosa Strains Isolated from Respiratory Samples from Cystic Fibrosis Patients Intended for Therapeutic Application

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S801-S801
Author(s):  
Jose Alexander ◽  
Daniel Navas ◽  
Marly Flowers ◽  
Angela Charles ◽  
Amy Carr
Keyword(s):  
Cystic Fibrosis ◽  
Host Range ◽  
Phage Therapy ◽  
Clinical Isolates ◽  
Clinical Samples ◽  
Plaque Morphology ◽  
Broad Host Range ◽  
Chronic Infections ◽  
Clinically Significant ◽  
Host Target

Abstract Background With the rise of the antimicrobial resistance between different genera and species of bacteria, Phage Therapy is becoming a more realistic and accessible option for patients with limited or no antimicrobial options. Being able to have rapid access to a collection of clinical active phages is key for rapid implementation of phage therapy. The Microbiology Department at AdventHealth Orlando is performing routine screening of environmental and patient samples for isolation of phages against non-fermenting Gram negative bacteria to develop a Phage Bank. Methods Protocols for phage isolation from environmental sources such as lakes, rivers and sewers and clinical samples were developed. A series of respiratory, throat, stool and urine samples were processed following an internal protocol that includes centrifugation, filtration and enrichment. Clinical samples were centrifugated for 10 minutes, filtered using 0.45µm centrifugation filters, seeded with targeted host bacteria (clinical isolates) and incubated at 35°C for 24 hours. The enriched samples were centrifugated and filtered for a final phage enriched solution. Screening and isolation were performed using the Gracia method over trypticase soybean agar (TSA) for plaque morphology and quantification. Host range screening of other clinical isolates of P. aeruginosa was performed using the new isolated and purified phages. Results 4 lytic phages against clinical strains of P. aeruginosa from patient with diagnosis of cystic fibrosis (CF), were isolated and purified from 4 different respiratory samples, including sputum and bronchial alveolar lavage. All phages showed phenotypical characteristics of lytic activity. 1 phage was active against 4 strains of P. aeruginosa, 1 phage was active against 2 strains of P. aeruginosa and the remaining 2 phages were active only against the initial host target strain. Conclusion With this study we demonstrated the potential use of clinical samples as source for isolating active bacteriophages against clinically significant bacteria strains. Clinical samples from vulnerable population of patients with chronic infections are part of our routine “phage-hunting” process to stock and grow our Phage Bank project for future clinical use. Disclosures All Authors: No reported disclosures

Sign in / Sign up

Export Citation Format

Share Document