Characterization of ATI, TK and IFN-alpha/betaR genes in the genome of the BeAn 58058 virus, a naturally attenuated wild Orthopoxvirus

Effect of the ati Gene Deletion on the Pathogenicity and Immunogenicity of the Vaccinia Virus

Among the nonvirion proteins of the vaccinia virus (VACV), a 94-kDa long protein is most abundantly present; the protein is a truncated form of the 150-kDa A-type inclusion (ATI) protein of the cowpox virus encoded by the ati gene. This VACV protein does not form intracellular ATIs, being as it is a major immunogen upon infection/immunization of humans or animals with the VACV. Antibodies specific to this protein are not virus-neutralizing. The present study focused on the effect of the production of this nonstructural major immunogenic VACV protein on the manifestation of pathogenicity and immunogenicity of the virus in the BALB/c mouse model of infection. In order to introduce a targeted deletion into the VACV LIVP genome, the recombinant integration/deletion plasmid pΔati was constructed and further used to generate the recombinant virus LIVPΔati. The pathogenicity of the VACV LIVP and LIVPΔati strains was studied in 3-week-old mice. The mice were intranasally infected with the viruses at a dose of 107 pfu; 50% of the animals infected with the parent LIVP strain died, while infection with the LIVPΔati strain led to the death of only 20% of the mice. Intradermal vaccination of mice aged 6- weeks with the LIVPΔati virus statistically significantly increased the production of VACV-specific IgG, compared to that after intradermal vaccination with VACV LIVP. Meanwhile, no differences were noted in the cell-mediated immune response to the vaccination of mice with VACV LIVP or LIVPΔati, which was assessed by ELISpot according to the number of splenocytes producing IFN-γ in response to stimulation with virus-specific peptides. Intranasal infection of mice with lethal doses of the cowpox virus or the ectromelia virus on day 60 post-immunization with the studied VACV variants demonstrated that the mutant LIVPΔati elicits a stronger protective response compared to the parent LIVP.

Lung microbiome of stable and exacerbated COPD patients in Tshwane, South Africa

Chronic obstructive pulmonary disease (COPD) is characterised by the occurrence of exacerbations triggered by infections. The aim of this study was to determine the composition of the lung microbiome and lung virome in patients with COPD in an African setting and to compare their composition between the stable and exacerbated states. Twenty-four adult COPD patients were recruited from three hospitals. Sputum was collected and bacterial DNA was extracted. Targeted metagenomics was performed to determine the microbiome composition. Viral DNA and RNA were extracted from selected samples followed by cDNA conversion. Shotgun metagenomics sequencing was performed on pooled DNA and RNA. The most abundant phyla across all samples were Firmicutes and Proteobacteria. The following genera were most prevalent: Haemophilus and Streptococcus. There were no considerable differences for alpha and beta diversity measures between the disease states. However, a difference in the abundances between disease states was observed for: (i) Serratia (3% lower abundance in exacerbated state), (ii) Granulicatella (2.2% higher abundance in exacerbated state), (iii) Haemophilus (5.7% higher abundance in exacerbated state) and (iv) Veillonella (2.5% higher abundance in exacerbated state). Virome analysis showed a high abundance of the BeAn 58058 virus, a member of the Poxviridae family, in all six samples (90% to 94%). This study is among the first to report lung microbiome composition in COPD patients from Africa. In this small sample set, no differences in alpha or beta diversity between stable and exacerbated disease state was observed, but an unexpectedly high frequency of BeAn 58058 virus was observed. These observations highlight the need for further research of the lung microbiome of COPD patients in African settings.

Seroprevalence and Risk Factors Possibly Associated with Emerging Zoonotic Vaccinia Virus in a Farming Community, Colombia

Dairy farmers had high rates of orthopoxvirus seropositivity and substantial illness associated with vaccinia-like lesions.

In 2014, vaccinia virus (VACV) infections were identified among farmworkers in Caquetá Department, Colombia; additional cases were identified in Cundinamarca Department in 2015. VACV, an orthopoxvirus (OPXV) used in the smallpox vaccine, has caused sporadic bovine and human outbreaks in countries such as Brazil and India. In response to the emergence of this disease in Colombia, we surveyed and collected blood from 134 farmworkers and household members from 56 farms in Cundinamarca Department. We tested serum samples for OPXV antibodies and correlated risk factors with seropositivity by using multivariate analyses. Fifty-two percent of farmworkers had OPXV antibodies; this percentage decreased to 31% when we excluded persons who would have been eligible for smallpox vaccination. The major risk factors for seropositivity were municipality, age, smallpox vaccination scar, duration of time working on a farm, and animals having vaccinia-like lesions. This investigation provides evidence for possible emergence of VACV as a zoonosis in South America.

Vaccinia Virus Natural Infections in Brazil: The Good, the Bad, and the Ugly

The orthopoxviruses (OPV) comprise several emerging viruses with great importance to human and veterinary medicine, including vaccinia virus (VACV), which causes outbreaks of bovine vaccinia (BV) in South America. Historically, VACV is the most comprehensively studied virus, however, its origin and natural hosts remain unknown. VACV was the primary component of the smallpox vaccine, largely used during the smallpox eradication campaign. After smallpox was declared eradicated, the vaccination that conferred immunity to OPV was discontinued, favoring a new contingent of susceptible individuals to OPV. VACV infections occur naturally after direct contact with infected dairy cattle, in recently vaccinated individuals, or through alternative routes of exposure. In Brazil, VACV outbreaks are frequently reported in rural areas, affecting mainly farm animals and humans. Recent studies have shown the role of wildlife in the VACV transmission chain, exploring the role of wild rodents as reservoirs that facilitate VACV spread throughout rural areas. Furthermore, VACV circulation in urban environments and the significance of this with respect to public health, have also been explored. In this review, we discuss the history, epidemiological, ecological and clinical aspects of natural VACV infections in Brazil, also highlighting alternative routes of VACV transmission, the factors involved in susceptibility to infection, and the natural history of the disease in humans and animals, and the potential for dissemination to urban environments.

Dairy production practices and associated risks for bovine vaccinia exposure in cattle, Brazil

A cross-sectional serosurvey was performed to identify environmental features or practices of dairy farms associated with risk for exposure to vaccinia-like viruses in dairy cattle in Brazil. Sera from 103 cows from 18 farms in Minas Gerais state were examined for Orthopoxvirus-neutralizing antibodies. A database of 243 binary or multiple-selection categorical variables regarding the physical features and surrounding ecology of each property was obtained. Thirteen of 46 presumptive predictor variables were found to be significantly associated with Orthopoxvirus serostatus by univariate logistic regression methods. Use of teat sanitizer and having felids on the property were independently associated with virus exposure by multivariable analysis. Rodents have long been suspected of serving as maintenance reservoirs for vaccinia-like viruses in Brazil. Therefore, domestic felids are not only effective predators of small rodent pests, but also their urine can serve as a deterrent to rodent habitation in buildings such as stables and barns. These results corroborate previous evidence of the high significance of rodents in the Vaccinia virus transmission cycle, and they also raise questions regarding the common use of teat sanitizers in dairy production areas.

Complete Genome Sequence of the BeAn 58058 Virus Isolated from Oryzomys sp. Rodents in the Amazon Region of Brazil

Here, we report the complete genome sequence of the BeAn 58058 virus (prototype) strain, isolated from a wild rodent Oryzomys sp. in the Utinga forest, Belém, state of Pará, Brazil in 1963. The genome of this virus showed similarity to the Poxviridae family, suggesting its inclusion in a possible new genus.

A resourceful giant: APMV is able to interfere with the human type I interferon system

Acanthamoeba polyphaga mimivirus (APMV) is a giant, double-stranded virus of the Mimiviridae family that was discovered in 2003. Recent studies have shown that this virus is able to replicate in murine and human phagocytes and might be considered a putative human pathogen that causes pneumonia. However, there is little data regarding APMV and its host defense relationship. In the present study, we investigated how some components of the interferon (IFN) system are stimulated by APMV in human peripheral blood mononuclear cells (PBMCs) and how APMV replication is affected by IFN treatment. Our results demonstrated that APMV is able to replicate in human PBMCs, inducing type I Interferons (IFNs) but inhibiting interferon stimulated genes (ISG) induction by viroceptor and STAT-1 and STAT-2 dephosphorylation independent mechanisms. We also showed that APMV is resistant to the antiviral action of interferon-alpha2 (IFNA2) but is sensitive to the antiviral action of interferon-beta (IFNB1). Our results demonstrated the productive infection of professional phagocytes with APMV and showed that this virus is recognized by the immune system of vertebrates and inhibits it. It provides the first data regarding APMV and the IFN system interaction and raise new and relevant evolutional questions about the relationship between APMV and vertebrate hosts.

Animal poxvirus vaccines: a comprehensive review

The family Poxviridae includes several viruses of medical and veterinary importance. Global concerted efforts combined with an intensive mass-vaccination campaign with highly efficaceious live vaccine of vaccinia virus have led to eradication of smallpox. However, orthopoxviruses affecting domestic animals continue to cause outbreaks in several endemic countries. Different kinds of vaccines starting from conventional inactivated/attenuated to recombinant protein-based vaccines have been used for control of poxvirus infections. Live virus homologous vaccines are currently in use for diseases including capripox, parapox, camelpox and fowlpox, and these vaccines are highly effective in eliciting (with the exception of parapoxviruses) long-lasting immunity. Attenuated strains of poxviruses have been exploited as vectored vaccines to deliver heterologous immunogens, many of them being licensed for use in animals. Worthy of note are vaccinia virus, fowlpox virus, capripoxvirus, parapoxvirus and canary pox, which have been successfully used for developing new-generation vaccines targeting many important pathogens. Remarkable features of these vaccines are thermostability and their ability to engender both cellular and humoral immune responses to the target pathogens. This article updates the important vaccines available for poxviruses of livestock and identifies some of the research gaps in the present context of poxvirus research.

Emergence and reemergence of vaccinia-like viruses: global scenario and perspectives

Among the members of the genus Orthopoxvirus (OPXV), vaccinia virus (VACV), the type species of the genus is a double-stranded DNA virus, belongs to the subfamily Chordopoxvirinae of the family Poxviridae. The causative agents of smallpox, VACV and Variola virus are mutually immunogenic and the type species of Orthopoxvirus, cause only mild complications in humans. Therefore, the VACV was used as a smallpox vaccine world over under mass immunization program promoted by World Health Organization, which lead to the variola eradication globally in 1979. Since then, no vaccination of human population has been carried out; however, vaccination has been continued for at-risk laboratory workers, military personnel and others working with recombinant VACV or other non-variola orthopoxviruses (OPXVs). There has now been a surge in the development of safer smallpox vaccines and understanding of the biology of VACV necessitating re-use of this vaccine in most vulnerable population, because of rise in bioterrorist threats globally. Also, globally there has been the emergence and re-emergence of vaccinia-like viruses (VLVs) in Brazil, buffalopox viruses in Egypt, Indonesia, India and its neighbouring countries like Nepal, Pakistan. Bioterrorism as well as emergence and re-emergence of the VLVs constitute a concern as 50 % of the population globally (40 % in USA) <30 years are unvaccinated and most vulnerable for smallpox reemergence. Thus, the search for new generation safer smallpox vaccine entails review of biology of VLVs in the smallpox-free world. In this review, we present occurrence of VLVs in the world with exhaustive discussion particularly on the emergence and re-emergence of these viruses in India and Brazil where VLVs are sufficiently studied.

A-type inclusion bodies: a factor influencing cowpox virus lesion pathogenesis

The family Poxviridae comprises the most complex animal DNA viruses. During some poxvirus infections, A-type inclusion bodies (ATIs), codified by the ati gene, are produced. Although some studies have compared poxviruses that encode these inclusion bodies with those that do not, the biological function of ATIs is poorly understood. A recombinant ati-deleted cowpox virus was constructed and compared with the wild-type virus in in vitro experiments including electron microscopy and plaque and viral growth assays. No significant differences were observed in vitro. This reinforces the conclusion that the inclusion body is not essential for in vitro viral replication and morphogenesis. Additionally, different lesion progressions in vivo were observed by macroscopic and histological analysis, suggesting that the presence or absence of ATIs could result in different healing dynamics. This is the first time that the role of ATIs during viral replication has been studied based solely on one variable, the presence or absence of ATIs.

Epidemic of unilateral panuveitis in children from Brazilian Amazonia: clinical and etiological aspects in seven patients

OBJECTIVES

To describe clinical presentation and results of diagnostic and therapeutic procedures in seven children from an epidemic of panuveitis in the Brazilian Amazonia, as well as environmental analysis and etiological aspects involved.

METHODS

Patients underwent full pediatric and ophthalmic examinations, B-scan, ultrasound biomicroscopy, and serological tests. Ocular samples were thoroughly analyzed, including two enucleation specimens. Environmental investigation encompassed water, soil, and river fauna.

RESULTS

All patients had bathed in the waters of a regional river, the Araguaia. Six of them presented with intermediate uveitis, with snowbanking. Five had cataract and four showed inferior endothelial opacity, with localized anterior synechiae. One showed total leukoma, with flat anterior chamber. Only two had active uveitis, one of them with anterior chamber nodule. Serology revealed high prevalence of anti-Toxocara canis immunoglobulin G (IgG) antibodies. In three cases, vitreous and lens samples disclosed spicules of freshwater sponges Drulia uruguayensis and D. ctenosclera, also detected in the waters of the river.

CONCLUSION

Freshwater sponge spicules could be potential new etiological agents of ocular pathology, but further studies are needed, considering the heterogeneity of the ocular lesions and results of serological and environmental studies.

Brazilian Vaccinia virus strains show genetic polymorphism at the ati gene

Nucleotide sequence comparison of the internal region of the ati gene of members of the Orthopoxvirus genera revealed that this gene is variable among different species, although within members of the same species it is considered to be well conserved. Previous studies indicated that there is genetic variability in the ati gene among some Brazilian Vaccinia virus strains. To further investigate this variability, we performed molecular analysis of the internal region of the ati gene of eight Brazilian Vaccinia virus strains. While the internal region of this gene in one strain was similar to the Western Reserve strain, four strains presented two blocks of deletions in the analyzed region, and the ati gene was almost entirely deleted from three other strains. These findings demonstrate that there is genetic polymorphism within the ati gene among different Brazilian Vaccinia virus strains.

Brazilian vaccinia viruses and their origins

Although the World Health Organization (WHO) declared global smallpox eradicated in 1980, concerns over emergent poxvirus infections have increased. Most poxvirus infections are zoonotic; exploring their genetic diversity will illuminate the genetic and evolutionary aspects of poxvirus infections, ecology, and epidemiology. In recent decades, several strains of the orthopoxvirus vaccinia virus (VACV) have been isolated throughout Brazil, including genetically distinct isolates within the same outbreak. To further investigate the diversity and origins of these viruses, we analyzed molecular data from 8 Brazilian VACV isolates and compared several genes involved in virus structure and pathogenicity. Genetic variation among isolates suggests that ancestral Brazilian VACVs existed before the beginning of the WHO smallpox eradication vaccination campaigns and that these viruses continue to circulate.

The vaccinia virus-stimulated mitogen-activated protein kinase (MAPK) pathway is required for virus multiplication

Early events play a decisive role in virus multiplication. We have shown previously that activation of MAPK/ERK1/2 (mitogen-activated protein kinase/extracellular-signal-regulated kinase 1/2) and protein kinase A are pivotal for vaccinia virus (VV) multiplication [de Magalhães, Andrade, Silva, Sousa, Ropert, Ferreira, Kroon, Gazzinelli and Bonjardim (2001) J. Biol. Chem. 276, 38353-38360]. In the present study, we show that VV infection provoked a sustained activation of both ERK1/2 and RSK2 (ribosomal S6 kinase 2). Our results also provide evidence that this pattern of kinase activation depends on virus multiplication and ongoing protein synthesis and is maintained independently of virus DNA synthesis. It is noteworthy that the VGF (VV growth factor), although involved, is not essential for prolonged ERK1/2 activation. Furthermore, our findings suggest that the VV-stimulated ERK1/2 activation also seems to require actin dynamics, microtubule polymerization and tyrosine kinase phosphorylation. The VV-stimulated pathway MEK/ERK1/2/RSK2 (where MEK stands for MAPK/ERK kinase) leads to phosphorylation of the ternary complex factor Elk-1 and expression of the early growth response (egr-1) gene, which kinetically paralleled the kinase activation. The recruitment of this pathway is biologically relevant, since its disruption caused a profound effect on viral thymidine kinase gene expression, viral DNA replication and VV multiplication. This pattern of sustained kinase activation after VV infection is unique. In addition, by connecting upstream signals generated at the cytoskeleton and by tyrosine kinase, the MEK/ERK1/2/RSK2 cascade seems to play a decisive role not only at early stages of the infection, i.e. post-penetration, but is also crucial to define the fate of virus progeny.

Belo Horizonte virus: a vaccinia-like virus lacking the A-type inclusion body gene isolated from infected mice

Here is described the isolation of a naturally occurring A-type inclusion body (ATI)-negative vaccinia-like virus, Belo Horizonte virus (VBH), obtained from a mousepox-like outbreak in Brazil. The isolated virus was identified and characterized as an orthopoxvirus by conventional methods. Molecular characterization of the virus was done by DNA cross-hybridization using Vaccinia virus (VACV) DNA. In addition, conserved orthopoxvirus genes such as vaccinia growth factor, thymidine kinase and haemagglutinin were amplified by PCR and sequenced. All sequences presented high similarity to VACV genes. Based on the sequences, phenograms were constructed for comparison with other poxviruses; VBH clustered consistently with VACV strains. Attempts to amplify the ATI gene (ati) by PCR, currently used to identify orthopoxviruses, were unsuccessful. Results presented here suggest that most of the ati gene is deleted in the VBH genome.

Araçatuba virus: a vaccinialike virus associated with infection in humans and cattle

We describe a vaccinialike virus, Araçatuba virus, associated with a cowpoxlike outbreak in a dairy herd and a related case of human infection. Diagnosis was based on virus growth characteristics, electron microscopy, and molecular biology techniques. Molecular characterization of the virus was done by using polymerase chain reaction amplification, cloning, and DNA sequencing of conserved orthopoxvirus genes such as the vaccinia growth factor (VGF), thymidine kinase (TK), and hemagglutinin. We used VGF-homologous and TK gene nucleotide sequences to construct a phylogenetic tree for comparison with other poxviruses. Gene sequences showed 99% homology with vaccinia virus genes and were clustered together with the isolated virus in the phylogenetic tree. Araçatuba virus is very similar to Cantagalo virus, showing the same signature deletion in the gene. Araçatuba virus could be a novel vaccinialike virus or could represent the spread of Cantagalo virus.