Entomopoxvirinae
INSECT PEST CONTROL BY VIRUSES
Davin Miller, ... David Dall, in Encyclopedia of Virology (Second Edition), 1999
Entomopoxvirinae
The Entomopoxvirinae (EPV) are a subfamily of the Poxviridae that are specific to insect hosts. EPV infections have been documented in four major orders of insect pests: the Lepidoptera, Coleoptera, Orthopteraand Diptera. The EPVs resemble the baculoviruses in a number of ways, including their production of occlusion bodies and their amenability to genetic modification. In addition, however, EPVs are capable of infecting a number of economically important pest species not affected by the Baculoviridae, including the desert locust(Schistocerca gregaria), possibly the most destructive pest species worldwide, and a variety of scarab beetle pests. To date the EPVs have received little attention as potential pest control agents, due largely to their slow speed of kill. However, several EPVs are capable of replicating in insect cells in culture, and this has enabled researchers to investigate the possibility of genetically modifying EPVs to enhance their speed of kill. One EPV showing particular promise in this respect is the H. armigera EPV (HaEPV). This virus infects several different economically important lepidopteran pests, grows readily in tissue culture, and can be genetically modified. Work is currently underway to increase the speed of kill of this virus in the same manner as for baculoviruses (see below).
Insect Pest Control by Viruses
M. Erlandson, in Encyclopedia of Virology (Third Edition), 2008
Poxviridae: Subfamily Entomopoxvirinae
Entomopoxviruses, subfamily Entomopoxvirinae, are typical poxviruses with large brick-shaped enveloped virions and a linear double-stranded DNA (dsDNA) 130–375 kbp genome. These large complex viruses replicate in the cytoplasm of infected cells and mature virions are typically occluded within proteinaceous OBs called spheroids. There are three recognized genera in the Entomopoxvirinae, distinguished by virion morphology, genome size, and host range: Alphaentomopoxvirus has been isolated exclusively from Coleoptera, Betaentomopoxvirus from Lepidoptera and Orthoptera, and Gammaentomopoxvirus from Diptera.
Entomopoxviruses have been investigated for their potential use as biological control agents against orthopteran insects from which other insect virus groups, including baculoviruses, have not been described. Melanoplus sanguinipes entomopoxvirus (MSEV) and Oedaleus senegalensis entomopoxvirus are of interest because they infect many of the major grasshopper and locust pest species.
Figure 1. Nymphs of the migratory grasshopper, Melanoplus sanguinipes, infected with Melanoplus sanguinipes entomopoxvirus (a) compared to uninfected nymphs (b).
Neurovirology
Philip E. Pellett, ... Thomas C. Holland, in Handbook of Clinical Neurology, 2014
Poxviruses
The poxvirus family (Poxviridae) contains two subfamilies (Chordopoxvirinae and Entomopoxvirinae). Poxviruses that naturally infect humans are chordoxpoxviruses that belong to the Orthopoxvirus, Molluscipoxvirus, Parapoxvirus, and Yatapoxvirus genera. Although best known for producing characteristic skin lesions, with respect to the nervous system, the most significant poxviruses are variola virus (eradicated from the wild), vaccinia virus, and monkeypox virus (all of genus Orthopoxvirus), and molluscum contagiosum virus (genus Molluscipoxvirus).
Poxvirus virions are large and complex (Fig. 2.1). They can be brick-shaped or ovoid, with lengths of 220–450 nm and widths and thicknesses of 140–260 nm. The virus genome has a condensed nucleoprotein structure in the core. In infectious intracellular mature virions, the core is surrounded by proteinaceous lateral bodies and an envelope containing non-glycosylated virus-encoded membrane proteins. Extracellular enveloped virions have a second envelope. Poxvirus genomes range in length from 135 to 375 kb of linear dsDNA and have hairpin structures at the genomic termini such that, if denatured, the genome becomes a single-stranded circle with a circumference double the genome length. Poxviruses encode ~ 200 proteins, which are expressed from unspliced transcripts that can be coded on either strand of the genome.
Poxvirus replication takes place in the cytoplasm, which is unusual among DNA viruses, and necessitates the use of a virus-encoded RNA polymerase. Virus entry is via endocytosis (Fig. 2.2, path A2) (Moss, 2012; Schmidt et al., 2012), followed by expression of early genes, some of which play roles in modulating host defenses, while others initiate subsequent steps of replication, which includes genome replication and expression of viral intermediate genes. Intermediate genes enable expression of late genes, whose translation products include virion proteins. Virion assembly takes place in specialized factories that form on cellular membranes near the nucleus. After proteolytic release of spherical immature virions from viral factories, the particles acquire their mature morphology; these virions are released by cell lysis. Some mature virions subsequently acquire a second envelope and are released by an exocytic process (Fig. 2.5, path 6).
Neurologic disease caused by poxvirus infections includes headaches that sometimes accompany the prodromal phase of infection with monkeypox virus and tanapox virus (Damon, 2011), and rare but severe encephalitis following primary vaccination with vaccinia virus (Moss, 2011). The frequency of postvaccination encephalomyelitis(PVEM) is dependent on the vaccinia strain used as the vaccine, with the strain used in the United States (New York Board of Health) being associated with relatively low PVEM incidence. PVEM develops 11–15 days after vaccination in adults and after 6–10 days in infants under 2 years of age, with symptoms consistent with demyelinating encephalomyelitis or direct infection of the CNS. CSF pressure can be elevated but cell counts and chemistry may be normal. Specific diagnosis is difficult, and vaccinia immune globulin has no proven value. The efficacy of newer antivirals (ST-246 and CMX001) is being evaluated; these drugs were used under emergency investigational new drug protocols to treat a patient with progressive vaccinia (Lederman et al., 2012).
Poxviruses
Jennifer Louten, in Essential Human Virology, 2016
Summary of Key Concepts
Section 15.1 Taxonomy
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The Poxviridae family contains 38 viruses. It is subdivided into Entomopoxvirinae and Chordopoxvirinae subfamilies. The Orthopoxvirus genus within Chordopoxvirinae contains nine viruses that include Variola virus, Vaccinia virus, Cowpox virus, and Monkeypox virus. Some of these have wide host ranges, while VARV infects humans exclusively.
Section 15.2 Clinical Course of Variola Infection
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Smallpox is caused by VARV. It is transmitted most commonly through respiratory droplets, although contact with infectious material can also transmit the virus.
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The incubation period for variola infection is 10–14 days. The prodrome is characterized by a high fever, headache, severe back pain, malaise, prostration, and sometimes vomiting and abdominal pain.
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The fever subsides within 2–4 days, at which point the rash begins as an enanthem. An exanthem follows within 24 hours. Herald spots appear on the face initially, followed by a centrifugal rash that is more prevalent on the extremities and face. Lesions are often present on the palms of the hands and soles of the feet.
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The lesions of the rash progress together through four stages. Macules are red spots that develop into raised papules, which fill with opalescent fluid to become blistery vesicles. Vesicles are firm to the touch, deep-seated, and can possess a central umbilication. These fill with pus to become pustules, which crust over into scabs that eventually separate from the lesion, leaving a depigmented scar behind. Scabs also contain infectious virions.
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Confluent smallpox occurs when the lesions are so closely associated that no skin is visible between them. It has a fatality rate >50%.
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Variola major has an overall fatality rate of around 30% with death occurring between days 10–16 of infection. Variola minor is less virulent, associated with <1% fatality. Variola major is classified into four principal clinical presentations: ordinary, modified, flat, and hemorrhagic smallpox. Flat and hemorrhagic forms are usually fatal.
Section 15.3 Poxvirus Replication Cycle
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Poxviruses are enveloped, brick-shaped viruses of approximately 350 nm by 250 nm, placing them among the largest human viruses. They possess large dsDNA genomes encoding ∼200 genes. ITRs at the end of the genome form a covalently closed, circularized genome. Most of our knowledge of poxvirusmolecular biology has been obtained by studying VACV.
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The viral dsDNA associates with at least four different proteins that organize the DNA into nucleosome-like structures, resembling eukaryotic chromatin. The dumbbell-shaped core of the virus is composed of a thinner inner layer and outer palisade layer. Lateral bodies assist in the shaping of the core.
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Poxvirus virions have two infectious forms. The MV is wrapped with a single envelope, while the EV possesses an additional lipid membrane.
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The VACV MV contains at least seven envelope proteins that together mediate adsorption of the virus to the cell. Notably, A27 and H3 interact with heparan sulfate, D8 binds to chondroitin sulfate, A26 binds to the extracellular matrix protein laminin, and L1 binds to an unidentified receptor. The EV contains membrane proteins A34 and B5 that bind to cell surface molecules and dissolve the outer envelope at the surface of the cell.
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The EFC comprises 11+ proteins that mediate the fusion of the MV envelope to the plasma membrane. Binding to cell surface integrin β1 causes endocytosis of the virion, and fusion occurs in the low pH of the endosome.
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The virus core travels to the endoplasmic reticulum using the microtubule network. An enclosed virus factory is created from the membranes of the endoplasmic reticulum. The virus factory is an infection-specific cytoplasmic domain where transcription, DNA replication, and nascent virion assembly takes place.
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Poxviruses do not require entry into the nucleus for replication because they carry all the proteins required to initiate transcription and processing of early mRNAs. The transcriptional system includes a DNA-dependent RNA polymerase, enzymes for adding a 5′-cap and 3′-poly(A) tail, and early gene transcriptionfactors.
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Transcription occurs in a cascade: early genes are transcribed that encode proteins required for DNA replication and transcription of intermediate genes, whose protein products result in the expression of late genes. Late gene products include structural proteins, as well as the transcription factors and enzymes that will be packaged into nascent virions. VACV has 118 early genes, 53 intermediate genes, and 38 late genes.
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The proteins required for DNA replication, which occurs in the virus factory, are translated from early mRNAs. In addition to the viral DNA polymerase E9, early gene products also include helicase–primase D5, DNA ligase A50, and several enzymes that increase the pool of nucleotides available within the cell. Concatemers are created that are cleaved into individual genomes that are packaged into new virions.
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VMAPs facilitate the formation of crescent membranes from endoplasmic reticulum membrane. Viral scaffold protein D13 creates a hexagon-shaped, honeycomb lattice on the convex surface of the crescent and continues the membrane curvature until it encloses the genomic DNA and core proteins. The sealed spherical body is known as an immature virion.
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The IV undergoes maturation to the MV with the removal of the D13 scaffold, addition of extra surface proteins to the viral membrane, and cleavage of core proteins by viral proteases I7 and G1. Proteins associated with the lateral bodies assist in the shaping of the core.
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Some of the MVs obtain a double membrane by passing through the Golgi network or an endosome, becoming a WV. The outer membrane of the WV fuses with the plasma membrane to release the EV.
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The EV can remain associated with the cell through the action of its outer envelope proteins, or it can be released when actin tails form beneath the cell surface, creating projections that promote the release of the virion toward neighboring cells. EVs are associated with localized, cell-to-cell spread whereas MVs are thought to be involved in infection between hosts.
Section 15.4 Eradication of Smallpox
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VARV likely emerged in Africa between 4000 and 10,000 years ago.
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Variolation was the intentional inoculation of an individual with smallpox material. It resulted in a milder form of disease than smallpox itself but still had a 2–3% fatality rate.
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In 1796, English country doctor Edward Jenner found that cowpox inoculation protected against smallpox infection. He widely publicized vaccination and provided vaccine material to anyone that requested it. Vaccination was soon adopted by other European countries and the United States.
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In the early 1950s, 50 million cases of smallpox were still occurring worldwide each year. The WHO championed the Intensified Global Eradication program to eliminate smallpox through vaccination.
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Eradication was possible because VARV only infects humans, does not induce subclinical or latent infections, and close contact is necessary for transmission. A lyophilized preparation allowed for the vaccine to be delivered to areas lacking refrigeration, and the bifurcated needle provided a consistent and reproducible manner to deliver the vaccine.
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Eradication was carried out through a surveillance and containment regimen that included identifying all infected persons and performing ring vaccination of his/her close contacts.
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The last case of variola major occurred in Bangladesh in 1975. The last known natural case of smallpox in the world was variola minor. It occurred in Somalia in October of 1977.
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Following smallpox eradication, the WHO recommended in 1980 that all countries cease vaccinating against smallpox because the risk of complications due to the live VACV preparation was then higher than the risk of contracting smallpox. Possible complications included inadvertent autoinoculation, generalized vaccinia infection, postvaccinial encephalitis, progressive vaccinia/vaccinia necrosum, and eczema vaccinatum.
The Double Stranded DNA Viruses
CONTRIBUTED BY, ... D. Raoult, in Virus Taxonomy, 2005
FAMILY POXVIRIDAE
TAXONOMIC STRUCTURE OF THE FAMILY
Family Poxviridae Subfamily Chordopoxvirinae Genus Orthopoxvirus Genus Parapoxvirus Genus Avipoxvirus Genus Capripoxvirus Genus Leporipoxvirus Genus Suipoxvirus Genus Molluscipoxvirus Genus Yatapoxvirus Subfamily Entomopoxvirinae Genus Alphaentomopoxvirus Genus Betaentomopoxvirus Genus Gammaentomopoxvirus VIRION PROPERTIES
MORPHOLOGY
Virions are somewhat pleomorphic, generally either brick-shaped (220–450 nm long × 140–260 nm wide × 140–260 nm thick) with a lipoprotein surface membrane displaying tubular or globular units (10–40 nm). They can also be ovoid (250–300 nm long × 160–190 nm diameter) with a surface membrane possessing a regular spiral filament (10–20 nm in diameter)(Fig. 1).
Figure 1. Negatively stained preparations of: (Upper left) an orthopoxvirus virion; (Upper center) a parapoxvirus virion and (upper right) a yatapoxvirus virion. Virions of orthopoxviruses and yatapoxviruses are morphologically similar. Yatapoxviruses are always enveloped, whereas envelopment of orthopoxviruses is relatively rare. Parapoxvirus virions are smaller and are characterized by regular surface structures. The schematic structure of the orthopoxvirus virions (Bottom left) reveals a condensed nucleoprotein organization of DNA. The core assumes a dumbell shape invaginated by the large lateral bodies, which are, in turn, enclosed within a protein shell about 12 nm thick – the outer membrane (or envelope), the surface of which appears to consist of irregularly arranged surface tubules, which in turn consist of small globular subunits. Some evidence suggests that the “dumbell” shape of cores may be an artifact of sample preparation. Virions released from the cell by exocytosis are enclosed within an envelope, which contains host cell lipids and several additional virus-specific polypeptides not present within intracellular virus. The schematic structure of a parapoxvirus virus (Orf virus, ORFV) (bottom right) reveals an outer membrane consisting of a single, long tubule that appears to be wound around the particle. The bar represents 100 nm. (Redrawn from Esposito and Fenner (2001) with permission).
Negative contrast images show that the surface membrane encloses a biconcave or cylindrical core that contains the genome DNA and proteins organized in a nucleoprotein complex. One or two lateral bodies appear to be present in the concave region between the core wall and a membrane. This virion form is known as intracellular mature virus (IMV). Some IMV is wrapped by an additional double layer of intracellular membrane to form intracellular enveloped virus (IEV). The IEV can be externalized and bound to the cell surface to form cell-associated enveloped virus (CEV) or released from the cell surface as extracellular enveloped virus (EEV). Some vertebrate viruses (e.g. isolates of Cowpox virus and Ectromelia virus) may also be sequestered within growing inclusion bodies. Others (e.g. entomopoxviruses) may be occluded into a preformed inclusion body.
PHYSICOCHEMICAL AND PHYSICAL PROPERTIES
Particle weight is about 5 × 10−15 g. S20w is about 5000S. Buoyant density of virions is subject to osmotic influences: in dilute buffers it is about 1.16 g/cm3, in sucrose about 1.25 g/cm3, in CsCl and potassium tartrate about 1.30 g/cm3. Virions tend to aggregate in high salt solution. Infectivity of some members is resistant to trypsin. Some members are insensitive to ether. Generally, virion infectivity is sensitive to common detergents, formaldehyde, oxidizing agents, and temperatures greater than 40°C. The virion surface membrane is removed by nonionic detergents and sulfhydryl reducing reagents. Virions are relatively stable in dry conditions at room temperature; they can be lyophilized with little loss of infectivity.
NUCLEIC ACID
Nucleic acids constitute about 3% of the particle weight. The genome is a single, linear molecule of covalently-closed, dsDNA, 130–375 kbp in length.
PROTEINS
Proteins constitute about 90% of the particle weight. Genomes encode 150–300 proteins depending on the species; about 100 proteins are present in virions. Virus particles contain many enzymes involved in DNA transcription or modification of proteins or nucleic acids. Enveloped virions have viral encoded polypeptides in the lipid bilayer, which surrounds the particle. Entomopoxviruses may be occluded by a virus-encoded, major structural protein, spheroidin. Similarly, orthopoxviruses may be within inclusion bodies again consisting of a single protein (the A-type inclusion [ATI] protein).
LIPIDS
Lipids constitute about 4% of the particle weight. Enveloped virions contain lipids, including glycolipids, that may be modified cellular lipids.
CARBOHYDRATES
Carbohydrates constitute about 3% of the particle weight. Certain viral proteins, e.g. hemagglutinin in the envelope of orthopoxviruses, have N- and C-linked glycans.
GENOME ORGANIZATION AND REPLICATION
The poxvirus genome comprises a linear molecule of dsDNA with covalently closed termini; terminal hairpins constitute two isomeric, imperfectly paired, “flip-flop” DNA forms consisting of inverted complementary sequences. Variably sized, tandem repeat sequencearrays may or may not be present near the ends (Fig. 2). Replication takes place predominately if not exclusively within the cytoplasm (Fig. 3). Entry into cells of intracellular virus (IMV) and extracellular enveloped virus (EEV) is suggested to be via different pathways. After virion adsorption, IMV entry into the host cell is probably by fusion with the plasma membrane after which cores are released into the cytoplasm and uncoated further. EEV entry, unlike IMV, may necessitate fusion with endosomal membranes to release the core.
Figure 2. Schematic representation of the genome of the WR strain of Vaccinia virus (AY243312): The genome is a linear double-stranded molecule with terminal hairpins, inverted terminal repeats (ITR), and a series of direct repeats within the ITRs. Each overlapping bar indicates gene conservation between the WR strain and all poxviruses, vertebrate poxviruses, and orthopoviruses. The bars are color coded according to the percentage of gene conservation across the indicated taxa.
Figure 3. The infectious cycle of Vaccinia virus (VACV): IMV, intracellular mature virus; EEV, extracellular enveloped virus. See text for details.
Polyadenylated, capped primary mRNA transcripts, representing about 50% of the genome, are initially synthesized from both DNA strands by enzymes within the core, including a virus encoded multisubunit RNA polymerase; transcripts are extruded from the core for translation by host ribosomes. During synthesis of early proteins, host macromolecular synthesis is inhibited. Virus reproduction ensues in the host cell cytoplasm, producing basophilic (B-type) inclusions termed “viroplasms” or “virus factories”. The genome contains closely spaced ORFs, lacking introns, some of which may partially overlap preceded by virus-specific promoters that temporally regulate transcription of three classes of genes. One class, the early genes, are expressed from partially uncoated virions prior to DNA replication (these encode many non-structural proteins, including enzymes involved in replicating the genome and modifying DNA, RNA, and proteins designed to neutralize the host response). Early genes also encode intermediate transcription factors. Intermediate genes, which encode late transcription factors, are expressed during the period of DNA replication and are required for subsequent late gene transcription. Finally, late genes are expressed during the postreplicative phase (these mainly encode virion structural proteins but also early transcription factors). Despite a cytoplasmic site of replication, there is mounting evidence for the requirement of host nuclear proteins in post-replicative transcription. The mRNAs are capped, polyadenylated at the 3′-termini, but not spliced. Many intermediate, late and some early mRNAs have 5′-poly(A) tracts, which precede the encoded mRNA. Early protein synthesis is generally decreased during the transition to late gene expression, but some genes are expressed from promoters with both early and late activity. Certain proteins are modified post-translationally (e.g. by proteolytic cleavage, phosphorylation, glycosylation, ribosylation, sulfation, acylation, palmitylation and myristylation). Proteolytic cleavage of late proteins is required for virion morphogenesis.
The replication of the DNA genome appears to be mainly through the action of viral enzymes. DNA replication appears to involve a self-priming, unidirectional, strand displacement mechanism in which concatemeric replicative intermediates are generated and subsequently resolved via specific cleavages into unit length DNAs that are ultimately covalently closed. Genetic recombination within genera has been shown, and may occur between daughter molecules during replication. Non-genetic genome reactivation generating infectious virus has been shown within, and between, genera of the Chordopoxvirinae.
Virus morphogenesis begins following DNA replication and expression of early, intermediate and late genes. Particle assembly is initiated with the formation of crescent-shaped membrane structuresin the intermediate compartment between the endoplasmic reticulum and the trans-Golgi network. Replicated, concatameric DNA is resolved into unit genomes and packaged, forming virion particles that mature into fully infectious IMVs. Some IMVs acquire an additional double layer of intracellular membrane derived from the early endosomes or the trans-Golgi network that contain unique virus proteins (IEV). These IEVs are transported to the periphery of the cell where fusion with the plasma membrane ultimately results in release of EEV or, if attached to the exterior surface of the plasma membrane, remain as CEV. While both IMVs and CEVs/EEVs are infectious, the external antigens on the two virus forms are different, and upon infection the two virion types probably bind to different cellular receptors and are likely uncoated by different mechanisms. Virus DNA and several proteins are organized as a nucleoprotein complex within the core of all infectious virions. The IMVs contain an encompassing surface membrane, lateral bodies, and the nucleoprotein core complex (see Fig. 1). For Vaccinia virus, the core wall has a regular subunit structure. Within the vaccinia virion, negative stain indicates that the core assumes a biconcave shape (Fig. 1) apparently due to the large lateral bodies. During natural infections, the virus is likely spread within an animal by extracellular virions that adhere to the cell surface (CEV) or are released from the cells (EEV) or through the movement of infected cells. Although the internal structure of vaccinia virions is revealed in thin sections, the detailed internal structure of parapoxvirus particles is less evident (Fig. 1). In negatively stained preparations of parapoxviruses, superimposition of dorsal and ventral views of the surface filament sometimes produces a distinctive “criss-cross” surface appearance.
ANTIGENIC PROPERTIES
Within each genus of the subfamily Chordopoxvirinae there is considerable serologic cross-protection and cross-reactivity. Neutralizing antibodies are genus-specific. The nucleoprotein antigen, obtained by treatment of virus suspensions with 0.04 M NaOH and 56°C treatment of virus suspensions, is highly cross-reactive among members. Orthopoxviruses have hemagglutinin antigens, although this is rare in other genera.
BIOLOGICAL PROPERTIES
Transmission of various member viruses of the subfamily Chordopoxvirinae occurs by (1) aerosol, (2) direct contact, (3) arthropods (via mechanical means), or (4) indirect contact via fomites; transmission of member viruses of the subfamily Entomopoxvirinaeoccurs between arthropods by mechanical means. Host range may be broad in laboratory animals and in tissue culture; however, in nature it is generally narrow. Many poxviruses of vertebrates produce dermal maculopapular, vesicular rashes after systemic or localized infections. Poxviruses infecting humans are zoonotic except for Molluscumcontagiosum virus (MOCV) and the orthopoxvirus Variola virus(VARV) (the etiologic agent of smallpox, now eradicated). Members may or may not be occluded within proteinaceous inclusions (Chordopoxvirinae: acidophilic (A-type) inclusion bodies, or Entomopoxvirinae: occlusions or spheroids). Occlusions may protect such poxviruses in environments where transmission possibilities are limited. Neutralizing antibodies and cell-mediated immunity play a major role in clearance of vertebrate poxvirus infections. Reinfection rates are generally low and usually less severe. Molluscum contagiosum infections may recur, especially by autoinoculation of other areas of the skin with virus derived from the original lesions (e.g., by scratching).
Other Poxviruses That Infect Humans
Brett W. Petersen, Inger K. Damon, in Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases (Eighth Edition), 2015
Definition
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Parapoxviruses, molluscum contagiosum, and yatapoxviruses are among the nonorthopoxvirus infections of humans. THEY ARE ACTUAL TRANS TER HUM, ESP HIV. how brett et al. got executed. - dr. f @ SS Waff 1960 et bf, dop spec - syph tubs.
Epidemiology
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Parapoxvirus infections most commonly occur in individuals with occupational exposures to infected sheep, cattle, or goats. ur fam. WHAT USA EAT et. MC.
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Molluscum contagiosum infection occurs worldwide and is spread through mild skin trauma, fomites, and sexual transmission. crop treatment virans. migrans. household insects. WATER SUPPLY. C-CON. AEROSOL TRANS. ANY HOST.
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Yatapoxvirus infections are rarely reported; infections are acquired through exposure to infected animals and potentially arthropod vectors and are usually geographically restricted to Central and East Africa. Non relevant infection 1/3.
Microbiology
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Poxviruses are a diverse group of large, complex double-stranded DNA viruses that replicate in the cytoplasm of the host cell.
https://www.sciencedirect.com/topics/immunology-and-microbiology/entomopoxvirinae
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