Detection of Vaccinia Virus in Urban Domestic Cats, Brazil.

We investigated possible vaccinia virus (VACV) in urban house cats in Brazil. Serum samples from 6 cats were positive for VACV by PCR, indicating likely VACV circulation among house cats in urban areas of Brazil. This finding highlights the importance of epidemiologic surveillance to avoid outbreaks among urban human populations.

Detection of Vaccinia Virus in Dairy Cattle Serum Samples from 2009, Uruguay.

We detected orthopoxvirus in 28 of 125 serum samples collected during 2009 from cattle in Uruguay. Two samples were PCR-positive for vaccinia virus and had sequences similar to those for vaccinia virus associated with outbreaks in Brazil. Autochthonous circulation of vaccinia virus in Uruguay and other South American countries cannot be ruled out.

Seroprevalence of Orthopoxvirus in rural Brazil: insights into anti-OPV immunity status and its implications for emergent zoonotic OPV.

BACKGROUND: Bovine vaccinia (BV) is a zoonosis caused by Vaccinia virus, a virus from Orthopoxvirus genus (OPV) that affects mainly cattle herds and humans in rural areas in Brazil. Because most studies have focused on outbreaks situations, data on BV epidemiology is limited. A cross sectional study in Brazilian rural areas during 2012-2013 was conducted to determine the neutralizing antibodies seroprevalence and risk factors for BV. METHODS: A structured questionnaire was applied to elicit demographics data and farming practices considered risk factors for BV exposure. Neutralizing anti-OPV antibodies were investigated using plaque reduction neutralization test. The neutralizing antibodies prevalence rates were calculated and the risk factor analysis was performed using multivariate logistic regression. RESULTS: Two hundred and forty participants were enrolled in this study with a prevalence of neutralizing antibodies of 30.8 % (95 % confidence interval [CI], 25.3-36.9). In multivariate analysis, age > 35 years (Odds Ratio [OR] = 18.2; CI 95 % = 7.7 - 43.2) and previous outbreak in property (OR = 3.9; C I95 % = 1.2 - 12.6) were independently associated with anti-OPV neutralizing antibodies. CONCLUSIONS: In this study, anti-OPV protective immunity (neutralizing antibody titers) was assessed in an endemic BV Brazilian rural area. Our findings indicate that epidemiological surveillance is required and should be applied by public health authorities to create interventions and/or prevention strategies to avoid viral spread causing future outbreaks among individuals who are under risk of infection.

Outbreak of severe zoonotic vaccinia virus infection, Southeastern Brazil.

In 2010, a vaccinia virus isolate caused an atypically severe outbreak that affected humans and cattle in Brazil. Of 26 rural workers affected, 12 were hospitalized. Our data raise questions about the risk factors related to the increasing number and severity of vaccinia virus infections.

Evaluating anti-Orthopoxvirus antibodies in individuals from Brazilian rural areas prior to the bovine vaccinia era.

Vaccinia virus naturally circulates in Brazil and is the causative agent of a zoonotic disease known as bovine vaccinia (BV). We retrospectively evaluated two populations from the Amazon and Southeast Regions. BV outbreaks had not been reported in these regions before sample collection. Neutralising antibodies were found in 13 individuals (n = 132) with titres ranging from 100 ≥ 6,400 neutralising units/mL. Univariate analysis identified age and vaccination as statistically significant risk factors in individuals from the Southeast Region. The absence of detectable antibodies in vaccinated individuals raises questions about the protection of smallpox vaccine years after vaccination and reinforces the need for surveillance of Orthopoxvirus in Brazilian populations without evidence of previous outbreaks.

Caraparu virus induces damage and alterations in antioxidant defenses in the liver of BALB/c mice after subcutaneous infection.

Oxidative stress is a disturbance in the oxidant-antioxidant balance leading to potential cellular damage. Most cells can tolerate a mild degree of oxidative stress because they have a system that counteracts oxidation that includes antioxidant molecules such as glutathione (GSH) and superoxide dismutase (SOD). Disruption of the host antioxidant status has been recognized as an important contributor to the pathogenesis of many viruses. Caraparu virus (CARV) is a member of group C of the Bunyaviridae family of viruses. In South American countries, group C bunyaviruses are among the common agents of human febrile illness and have caused multiple notable outbreaks of human disease in recent decades; nevertheless, little is known about the pathogenic characteristics of these viruses. The purpose of this study was to examine the hepatic pathogenesis of CARV in mice and the involvement of oxidative stress and antioxidant defenses on this pathology. Following subcutaneous infection of BALB/c mice, CARV was detected in the liver, and histopathology revealed acute hepatitis. Increased serum levels of aspartate and alanine aminotransferases (AST/ALT) and greater hepatic expression of the proinflammatory cytokine tumor necrosis factor-α (TNF-α) were found in infected animals. CARV infection did not alter the biomarkers of oxidative stress but caused an increase in GSH content and altered the expression and activity of SOD. This is the first report of an alteration of oxidative homeostasis upon CARV infection, which may, in part, explain the hepatic pathogenesis of this virus, as well as the pathogenesis of other Bunyaviridae members.

Study of vaccinia and cowpox viruses' replication in Rac1-N17 dominant-negative cells.

Interfering with cellular signal transduction pathways is a common strategy used by many viruses to create a propitious intracellular environment for an efficient replication. Our group has been studying cellular signalling pathways activated by the orthopoxviruses Vaccinia (VACV) and Cowpox (CPXV) and their significance to viral replication. In the present study our aim was to investigate whether the GTPase Rac1 was an upstream signal that led to the activation of MEK/ERK1/2, JNK1/2 or Akt pathways upon VACV or CPXV' infections. Therefore, we generated stable murine fibroblasts exhibiting negative dominance to Rac1-N17 to evaluate viral growth and the phosphorylation status of ERK1/2, JNK1/2 and Akt. Our results demonstrated that VACV replication, but not CPXV, was affected in dominant-negative (DN) Rac1-N17 cell lines in which viral yield was reduced in about 10-fold. Viral late gene expression, but not early, was also reduced. Furthermore, our data showed that Akt phosphorylation was diminished upon VACV infection in DN Rac1-N17 cells, suggesting that Rac1 participates in the phosphoinositide-3 kinase pathway leading to the activation of Akt. In conclusion, our results indicate that while Rac1 indeed plays a role in VACV biology, perhaps another GTPase may be involved in CPXV replication.

Group 2 vaccinia virus, Brazil.

In 2011, vaccinia virus caused an outbreak of bovine vaccinia, affecting dairy cattle and dairy workers in Brazil. Genetic and phenotypic analyses identified this isolate as distinct from others recently identified, thereby reinforcing the hypothesis that different vaccinia virus strains co-circulate in Brazil.

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.

Identification of a phylogenetically distinct orthobunyavirus from group C.

Apeu virus (APEUV) (family Bunyaviridae, genus Orthobunyavirus) was plaque purified and characterised by serological and molecular analysis. Neutralising assays confirmed cross-reactivity between purified APEUV clones and the Caraparu virus complex of group C orthobunyaviruses. Partial sequencing of the L, M and S segments of one APEUV clone (APEUV-CL5) was carried out. A phylogenetic tree constructed with the L amino acid sequences clustered APEUV-CL5 within the genus Orthobunyavirus, confirming its serological classification. Analysis of M segment sequences clustered APEUV-CL5 in the Caraparu virus complex (Group C), in agreement with serological tests and previous molecular characterisation. However, the sequence of the nucleocapsid gene (N) gave low identity values when compared to those of the group C viruses. The phylogenetic tree based on N nucleotide sequences clustered APEUV-CL5 next to the California and Bwamba groups. This remarkable S nucleotide variability suggests that APEUV-CL5 could be a genetic reassortant and that this evolutionary mechanism is present in the history of the group C viruses.

Rapid detection of Orthopoxvirus by semi-nested PCR directly from clinical specimens: a useful alternative for routine laboratories.

Orthopoxvirus (OPV) has been associated with worldwide exanthematic outbreaks, which have resulted in serious economic losses as well as impact on public health. Although the current classical and molecular methods are useful for the diagnosis of OPV, they are largely inaccessible to unsophisticated clinical laboratories. The major reason for the inaccessibility is that they require both virus isolation and DNA manipulation. In this report, a rapid, sensitive and low-cost semi-nested PCR method is described for the detection of OPV DNA directly from clinical specimens. A set of primers was designed to amplify the conserved OPV vgf gene. The most useful thermal and chemical conditions were selected and minimum non-inhibitory dilutions were determined. More than 100 Brazilian Vaccinia virus (VACV) field clinical specimens were tested using this semi-nested PCR in order to confirm its applicability. Cowpox virus was also detected by PCR from the ear scabs of scarified Balb/c mice. In addition, the method was highly sensitive for the detection of VACV DNA in murine blood and excreta, which are among the suggested reservoirs of OPV. Together, these data suggest that semi-nested PCR can be used for initial screening for OPV and as a routine diagnostic laboratory method.

Brazilian Vaccinia virus strains are genetically divergent and differ from the Lister vaccine strain.

Vaccinia virus is responsible for an important zoonotic disease affecting dairy cattle and humans in Brazil, but little is known about the origin, epidemiology and evolution of these Brazilian Vaccinia virus strains. In this work, seven Brazilian Vaccinia virus strains and the Lister-derived Brazilian vaccine strain, named Lister-Butantan, were compared based on the sequences of ten host range and virulence related genes. Comparison of Brazilian Vaccinia virus strains with Lister-Butantan revealed several differences. Phylogenetic analyses confirmed the existence of genetically distinct Brazilian Vaccinia virus groups and has not thus far demonstrated a close relationship between Brazilian strains and Lister-Butantan. In this study, the BeAn58058 and SPAn232 strains were grouped together with the Belo Horizonte and Guarani P1 strains. Additionally, genetic polymorphisms in host range and virulence genes as well as differences in the deduced amino acid sequences were detected among Brazilian Vaccinia virus. This genetic diversity may result in a plethora of different biological properties presented by Brazilian Vaccinia virus, including differences in adaptation to the host as well as pathogenic properties. Furthermore, co-circulation of these divergent strains could increase the possibility of recombination events in nature, leading to the formation of new variants with unpredictable pathogenic potential.

Increased expression of 2'5'oligoadenylate synthetase and double-stranded RNA dependent protein kinase messenger RNAs on affected skin of systemic sclerosis patients.

Scleroderma or systemic sclerosis (SSc) is an autoimmune disorder of unknown aetiology characterized by excessive collagen synthesis and subsequent deposition on the skin and various internal organs. Interferons (IFNs) are well-known immunomodulators and inhibitors of collagen production. However, IFN therapy has been implicated in the development or exacerbation of several autoimmune diseases, including SSc. We analyzed the expression of several interferon-stimulated genes (ISGs) in affected skin of SSc patients (skin tissue and cultured skin fibroblasts). A set of ISGs (PKR, 2'5'OAS, MxA, and 6-16) was analyzed by real-time PCR using RNA extracted from cultured skin fibroblasts and skin tissue of normal individuals and SSc patients. Both normal and SSc affected skin cultured fibroblasts were sensitive to the IFN treatment and presented similar levels of all ISGs tested. However, PKR and 2'5'OAS mRNA expression levels were significantly higher in the affected skin tissue of SSc patients when compared to normal controls. These data suggest that the IFN system plays a role in the pathogenesis of SSc.

The detection of Vaccinia virus confirms the high circulation of Orthopoxvirus in buffaloes living in geographical isolation, Marajó Island, Brazilian Amazon.

In Brazil, serologic evidence of Orthopoxvirus (OPV) circulation showed positivity around 20% in cattle, humans, monkeys and rodents. Although OPV seropositivity has been described in buffalo herds in southeastern Brazil, no Vaccinia virus (VACV) (member of genus OPV) outbreaks in buffalo herds have been described in this country. This study aimed to investigate the detection of anti-OPV antibodies and to study the OPV genome in Brazilian buffalo herds. Our results demonstrated a high OPV seropositivity in buffalo herds on Marajó Island and molecular data confirmed the circulation of VACV. The geographical isolation conditionmight be a sine qua non condition to explain our results.

Infection of the central nervous system with dengue virus 3 genotype I causing neurological manifestations in Brazil.

A case of dengue virus 3 (DENV-3) genotype I infection with neurological manifestations occurred in Belo Horizonte, Minas Gerais in October 2012. The serotype was detected by PCR, and the genotype was assessed by sequencing and phylogenetic analysis of the C-prM region. The virus causing neurological manifestations clustered with other sequences of DENV-3 genotype I. Because neurological manifestations of DENV are possibly misdiagnosed in Brazil, this study serves as an alert of the importance of DENV diagnoses in CNS infections.

RAP1 GTPase overexpression is associated with cervical intraepithelial neoplasia.

RAP1 (RAS proximate 1), a small GTP-binding protein of the RAS superfamily, is a putative oncogene that is highly expressed in several malignant cell lines and types of cancers, including some types of squamous cell carcinoma. However, the participation of RAP1 in cervical carcinogenesis is unknown. We conducted a cross-sectional study of paraffin-embedded cervical biopsies to determine the association of RAP1 with cervical intraepithelial neoplasia (CIN). Standard and quantitative immunohistochemistry assessment of RAP1 expression in fixed tissue was performed on 183 paraffin-embedded cervical biopsies that were classified as normal or non-dysplastic mucosa (NDM) (n = 33); CIN grade 1 (n = 84) and CIN grade 2/3 (n = 66). A gradual increase in RAP1 expression in NDM < CIN 1 < CIN 2/3 (p<0.001) specimens was observed and was in agreement with the histopathologic diagnosis. A progressive increase in the RAP1 expression levels increased the risk of CIN 1 [odds ratio (OR) = 3.50; 95% confidence interval (CI) 1.30-10.64] 3.5 fold and the risk of CIN 2/3 (OR = 19.86, 95% CI 6.40-70.79) nearly 20 fold when compared to NDM. In addition, stereotype ordinal regression analysis showed that this progressive increase in RAP1 expression more strongly impacted CIN 2/3 than CIN 1. Our findings suggest that RAP1 may be a useful biomarker for the diagnosis of CIN.

Protease nexin-1 messenger RNA levels are not affected by serum or interferon beta in cultured systemic sclerosis fibroblasts.

The aim of the present study was to analyze the effect of serum and human recombinant beta interferon (rIFNbeta) treatment on PN-1 mRNA levels in cultured dermal fibroblasts obtained from the skin of healthy donors and from lesional skin of systemic sclerosis (SSc) patients with the limited (CREST syndrome) or the diffuse form of SSc. Total RNA was isolated from fibroblasts derived from the skin of healthy individuals and from lesional skin of patients with CREST syndrome and the diffuse form of SSc cultured under different conditions (1% or 10% serum-supplemented medium) and treated with 500 IU/ml of rIFNbeta. PN-1 gene expression was assessed by Northern blot analysis. We detected variable PN-1 mRNA levels in normal control fibroblasts as well as in SSc fibroblasts under the different culture conditions (1% or 10% serum-supplemented medium). Accumulated PN-1 mRNA levels found in normal cultured fibroblasts were similar to or even higher than in SSc fibroblasts. PN-1 messenger levels were not significantly altered by IFNbeta treatment in normal or SSc cultured fibroblasts despite the presence of an IFN-stimulated responsive element (ISRE) in the promoter of the PN-1 gene. Our findings suggest that PN-1 expression in SSc fibroblasts at the mRNA level requires further investigation in a large number of SSc patients to better characterize the role of this serpin in the pathogenesis of SSc. We conclude that the transcriptional regulation of PN-1 is not associated with IFNbeta, an antifibrotic cytokine naturally produced by fibroblasts.