Characterization of new strains of Pseudorabies virus in Argentina: Detection of interspecies transmission.

Background: Aujeszky's disease is mainly a swine disease, still endemic worldwide. It can infect other mammalians, including human beings, and it is usually fatal with nervous symptoms. Ever since the disease was detected in 1988 in Argentina, many outbreaks have been reported involving both feral swine and dogs.

Fibropapillomatosis Associated with Chelonid alphaherpesvirus 5 (ChHV5) in a Green Turtle Chelonia mydas in Argentine Waters.

Fibropapillomatosis is a debilitating neoplastic disease associated with Chelonid alphaherpesvirus 5 (ChHV5) infection. We detected the Atlantic variant of ChHV5 associated with a fibropapilloma in a green turtle (Chelonia mydas) found stranded on the western coast of Rio de la Plata, Argentina. This is the southernmost registered case for the southwestern Atlantic.

Clinical and molecular aspects of veterinary coronaviruses.

Coronaviruses are a large group of RNA viruses that infect a wide range of animal species. The replication strategy of coronaviruses involves recombination and mutation events that lead to the possibility of cross-species transmission. The high plasticity of the viral receptor due to a continuous modification of the host species habitat may be the cause of cross-species transmission that can turn into a threat to other species including the human population.

Argentinian small ruminant lentivirus (SRLV) p55gag antigen fused to maltose binding protein to use in SRLV serological confirmatory diagnosis.

The complete gag gene from small ruminant lentiviruses (SRLV) encodes for a polyprotein of 55 kDa, known as p55gag. p55gag presents multiple antigenic epitopes, which can be recognized by antibodies, increasing the opportunity to detect SRLV-positive animals. Therefore, this polyprotein is considered an excellent candidate to use in diagnostic tests to detect antibodies against SRLV.

Evidence of porcine circovirus type 2 and co-infection with ungulate protoparvovirus 1 (porcine parvovirus) in mummies and stillborn piglets in subclinically infected farm.

Porcine circovirus type 2 (PCV2) and protoparvovirus 1 (PPV) were detected as single infection (6/131) and (11/131) respectively, or co-infection (6/131) in fetuses and stillborn piglets from normal deliveries in a farm without reproductive problems. Twenty in twenty-three positive samples were over 70 days of gestation, which is when the fetus becomes immunocompetent, and the presence of a NADL-2 PPV strain suggests fetal immune system impairment. Phylogenetic analysis of sequences obtained showed that 8/9 sequences are related to cluster 13 and the remaining is grouped into cluster 11 sequences.

First detection and genetic characterization of porcine circovirus type 3 (PCV3) in Argentina and its association with reproductive failure.

Porcine circovirus type 3 (PCV3) is considered a new circovirus and since it first description has been widely reported in most of the swine-producing countries. Multisystemic inflammation and reproductive failure are consistent and concerning issues associated with PCV3 infection. This report describes the clinical and pathological features of a chronic reproductive disorder in a swine herd in Argentina associated with the presence of PCV3.

Host range of Triatoma virus does not extend to Aedes aegypti and Apis mellifera.

Vector control is the most effective method to prevent transmission of Chagas disease. Control is mostly made through chemical insecticides although they have negative impact on wild pollinators, such as bees. Reducing pesticide use through biological alternatives could minimize the damage to these beneficial insects.

Study of horn flies as vectors of bovine leukemia virus.

Bovine leukemia virus (BLV) is the agent responsible for enzootic bovine leukosis, the most common neoplastic disease in cattle. The horn fly, a major hematophagous pest of cattle, is able to transmit different diseases in cattle. However, its implication in BLV transmission under a natural environment is still discussed.

First isolation and molecular characterization of Suid herpesvirus type 1 from a domestic dog in Argentina.

Since Aujeszky`s disease (pseudorabies), which is caused by Suid herpesvirus type 1 (SuHV-1), was first notified in Argentina in 1978, many SuHV-1 strains have been isolated from swine. However, this disease can affect other vertebrates, such as dogs (secondary hosts), and lead to fatal neurological disease. The objective of the current work is to report the first isolation and molecular characterization of SuHV-1 from a dead domestic dog from Santa Fe Province (Argentina), which had had nervous signs compatible with pseudorabies.

Can Triatoma virus inhibit infection of Trypanosoma cruzi (Chagas, 1909) in Triatoma infestans (Klug)? A cross infection and co-infection study.

Triatoma virus occurs infecting Triatominae in the wild (Argentina) and in insectaries (Brazil). Pathogenicity of Triatoma virus has been demonstrated in laboratory; accidental infections in insectaries produce high insect mortality. When more than one microorganism enters the same host, the biological interaction among them differs greatly depending on the nature and the infection order of the co-existing species of microorganisms.

First isolation and nucleotide comparison of the gene of the caprine arthritis encephalitis virus circulating in naturally infected goats from Argentina.

Caprine arthritis encephalitis virus (CAEV) has been reported in different countries worldwide, based on serological and molecular detection. In Argentina, the prevalence of CAEV infections is increasing, with goats showing symptoms associated mostly with cachexia and arthritis. Although in Argentina the virus has been detected by serology, it has never been isolated or characterized.

Production of pseudorabies virus recombinant glycoprotein B and its use in an agar gel immunodiffusion (AGID) test for detection of antibodies with sensitivity and specificity equal to the virus neutralization assay.

Pseudorabies virus (PrV) causes Aujeszky's disease (AD), which affects mainly swine, but also cattle, sheep, and wild animals, resulting in substantial economic losses due to animal mortality and lost productivity worldwide. To combat PrV, eradication programs using PrV strains lacking the gene encoding glycoprotein E (gE) are ongoing in several countries. These eradication programs have generated a currently unmet demand for affordable, easy-to-use, and sensitive tests that can detect PrV infection in pigs infected with either wild-type virus or vaccine strain (gE-deleted) virus.

Modelling the potential geographic distribution of triatomines infected by Triatoma virus in the southern cone of South America.

Background: Triatoma virus (TrV) is the only entomopathogenous virus identified in triatomines. We estimated the potential geographic distribution of triatomine species naturally infected by TrV, using remotely sensed and meteorological environmental variables, to predict new potential areas where triatomines infected with TrV may be found.

Methods: Detection of TrV infection in samples was performed with RT-PCR.

Phylogenetics based on partial ORF2 of triatoma virus in triatomines collected over a decade from domiciliary habitats.

The only virus sequenced and studied in triatomines is the Triatoma virus, from the Dicistroviridae family, which causes delayed development, reduced oviposition, and premature death of infected insects. With the goal of expanding the sequences already obtained in previous years and verifying if any changes occurred in their genomic sequences, 68 samples of triatomines from several provinces of Argentina were analyzed. Sixteen positive samples were obtained by Reverse Transcription (RT)-polymerase chain reaction using the VP3-VP1 subregion of open reading frame-2 as a diagnostic method; after sequencing, 11 samples were obtained from Triatoma infestans.

First study of different insect cells to triatoma virus infection.

The use of viruses for biological control is a new option to be considered. The family Dicistroviridae, which affects only invertebrates, is one of the families that have been proposed for this purpose. The Triatoma virus (TrV), a member of this family, affects triatomine transmitters of Chagas disease, which is endemic in Latin America but also expanding its worldwide distribution.

Detection of triatomine infection by Triatoma virus and horizontal transmission: protecting insectaries and prospects for biological control.

Triatoma virus (TrV) is the only triatomine entomopathogenic virus identified so far. Propagation of TrV in insectaries depends on handling procedures and triatomine population dynamics. The effects of propagation can be devastating and entire colonies must often be sacrificed to prevent spread of the virus throughout the insectary.

Development of a peptide ELISA for the diagnosis of Equine arteritis virus.

A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed.

Equine arteritis virus gP5 protein induces apoptosis in cultured insect cells.

Equine Arteritis Virus (EAV) has been shown to induce apoptosis in vitro but the induction of this mechanism has not been previously associated with any viral gene product. In this work, we found a cytotoxicity effect of the EAV gP5 protein on baculovirus-insect cells and a low yield of protein recovery. Besides, different morphological features by electron transmission microscopy, DNA fragmentation in agarose gel, TUNEL analysis and caspase 3 activity were found.

First description of hemagglutination by a virus belonging to the family Dicistroviridae.

Triatoma virus is the only virus whose genome has been sequenced and studied in triatomines. It belongs to the family Dicistroviridae. In order to detect whether TrV has the ability to agglutinate erythrocytes of domestic and laboratory animals, we performed a hemagglutination assay.

Presence of Gumprecht shadows (smudge cells) in bovine leukemia virus-positive cattle.

Enzootic Bovine Leukosis is a chronic disease caused by the bovine leukemia virus (BLV). Smudge cells, also known as Gumprecht shadows, are not simple artifacts of slide preparation, but ragged lymphoid cells found mainly in peripheral blood smears from human patients with chronic lymphocytic leukemia. In this study, we report the presence of Gumprecht shadows in peripheral blood from BLV-positive cattle.

Expression and purification of Suid Herpesvirus-1 glycoprotein E in the baculovirus system and its use to diagnose Aujeszky's disease in infected pigs.

Suid Herpesvirus 1 (SHV-1) is the etiological agent of Aujeszky's disease (AD), which affects swine herds worldwide and causes substantial economic losses due to animal mortality and lost productivity. In order to eradicate SHV-1, vaccination programs using viruses lacking the gene encoding glycoprotein E (gE) are ongoing in several countries. These eradication programs have generated a currently unmet demand for affordable and sensitive tests that can detect SHV-1 infection, yet distinguish between infected and vaccinated pigs.

Analysis of the pX region of bovine leukemia virus in different clinical stages of Enzootic Bovine Leukemia in Argentine Holstein cattle.

Bovine leukemia virus (BLV) infection in cattle causes Enzootic Bovine Leukemia (EBL). About 30% of infected cattle develop persistent lymphocytosis (PL), a 0.1-5% develops tumors, and a 70% remains asymptomatic in an aleukemic stage (AL).

Expression of p24 gag protein of bovine leukemia virus in insect cells and its use in immunodetection of the disease.

Bovine leukemia is a common retroviral infection of cattle. The disease is characterized by a strong immunological response to several viral proteins, but the antibodies against p24 and gp51 are predominant. In this study, a recombinant baculovirus containing the gag gene p24 was constructed and the protein, used as antigen, analyzed by western blot and an indirect in-house rp24-ELISA test.

New Triatoma virus hosts in wild habitats of Argentina.

Triatoma virus (TrV), a member of the Dicistroviridae family, replicates in intestinal epithelial cells, causing delayed development and death of infected individuals. The aims of this study were to find naturally infected species of Triatominae in the wild in the region endemic for Chagas disease and analyze and compare the sequence diversity of TrV obtained from different Triatominae. A total of 253 Triatominae belonging to 10 species were captured by active or passive collection.