Rabies virus (RABV) causes a neurological disease in warm-blooded animals that is nearly always fatal. In this study, we analyzed the matrix (M) genes in 10 Korean street RABV strains isolated from two Provinces during 2011-2013. The M genes in these 10 Korean strains were highly conserved during 1999-2013. Phylogenetic analysis revealed they were closely related to the M genes of RABVs isolated in northeastern China. Specific amino acid substitutions were identified in the KRVB1206, KRVF1301, and BV9901PJ strains. However, functional domains, including those involved in virus production and pathogenicity, were conserved in all 10 strains.

After the original identification of canine parvovirus (CPV) type 2 (CPV-2) in 1978, new antigenic variants such as CPV-2a, CPV-2b and CPV-2c have become widespread in the most countries. In this study, the genetic analysis of canine parvovirus was investigated in a total of 13 CPV vaccines, which have been licensed in Korea since late 1980s, and a field isolate of CPV from a dog with CPV infection clinical symptom. The partial VP2 gene of CPV was amplified and sequenced from 13 vaccine strains and one field isolate. The results showed that of the 13 vaccine strains, 10 strains belong to the CPV-2, 2 strains to CPV-2b, the remaining and one isolate to CPV-2a type, respectively. Several mutations of amino acids were detected at residues of the critical region of the commercial vaccine strains. These data suggest that new type of vaccines containing CPV-2a or CPV-2b/2c type may be required for the better prevention of new CPV infection in dog population in Korea, because CPV-2 contained in most licensed vaccines has been replaced by antigenic variants designated CPV-2a or CPV-2b/c in the worldwide dog population.

Hantaviruses are causative agents of some severe human illnesses, including hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). The viruses are maintained by rodent hosts, and humans acquire infection by inhaling virus-contaminated excreta from infected animals. To examine the epidemiology of hantavirus infections in Japan and Far East Russia, we conducted epidemiological surveys in these regions. In Japan, anti-hantavirus antibodies were found in four rodent species, Clethrionomys rufocanus, Rattus norvegicus, R. rattus, and Apodemus speciosus. Although no new HFRS cases have been officially reported over the past 20 years in Japan, one member of the Japan Ground Self-Defense Force did test positive for hantavirus antibody. Repeated surveys in Far East Russia have revealed that two distinct hantavirus types cause severe HFRS in this region. Hantavirus sequences identified from A. peninsulae, fetal HFRS cases in Vladivostok, and Amur virus are highly similar to each other (92% identity) , but they are less similar (-84% identity) to the prototypical Hantaan virus, which is carried by A. agrarius. Phylogenetic analysis also indicates that Amur and A. peninsulae -associated viruses are distinct from Hantaan virus, suggesting that A. peninsulae is the reservoir animal for Amur virus, which causes severe HFRS. From HFRS patients in the Khabarovsk region, we identified viruses with nucleotide sequences that are more similar to Far East virus (96%identity) than to the Hantaan (88-89%identity) or Amur (81-83% identity) viruses. Phylogenetic analysis also indicates that the viruses from Khabarovsk HFRS patients are closely related to the Far East virus, and distinct from Amur virus.

Forty-seven Newcastle disease virus (NDV) strains isolated from fecal samples of waterfowls in Alaska and Siberia from 1991 to 1996 were analyzed for their virulence. None of the viruses formed plaques on MDBK cells in the absence of trypsin. Of these, 29 strains showed virulent character by the mean death time with the minimum lethal dose in chicken embryos comparable to velogenic NDV strains. Of the 29 strains, 11 were sequenced for their fusion protein (F) gene. The results showed that 5 of them contained a pair of dibasic amino acids at the cleavage site of the F, which is of a virulent type. The present results suggest that potentially virulent strains of NDV are maintained in migratory waterfowl populations in nature, and that some of those may be transmitted to domestic poultry and acquire pathogenicity during passages in chicken population

Amostras do vírus da raiva (n = 17) isoladas de bovinos (n = 11), equinos (n = 4) e bubalinos (n = 2) procedentes do Pará (n = 7), Tocantins (n = 6) e Rondônia (n = 4) foram submetidas à técnica de RT-PCR para amplificação parcial dos genes da Nucleoproteína (N) e Glicoproteína (G). As sequências nucleotídicas obtidas foram analisadas pelo método de reconstrução filogenética Neighbor-Joining com o modelo evolutivo Kimura 2-parâmetros. Todas as 17 amostras pertenceram ao cluster A, que se encontrou na linhagem associado com morcego hematófago Desmodus rotundus. A análise filogenética baseada nos genes N e G, sugere a presença de cinco sublinhagens (A1-A5) e sete sublinhagens (A1-A7), respectivamente. Quando se compara ambas as filogenias, as sublinhagens A1 até A3 mostram composição e distribuição geográfica concordante, já a diversidade observada na composição das sublinhagens restantes é atribuída ao uso de sequências de diferentes alinhamentos. A glicoproteína mostrou marcadores moleculares nas sublinhagens A2, A3, A4 e A7, o que fornece elementos para melhor compreensão da epidemiologia molecular da raiva das linhagens circulantes na Amazônia Brasileira. | Rabies virus samples (n = 17) isolated from bovines (n = 11), equines (n = 4) and buffalo (n = 2) from Pará State (n = 7), Tocantins (n = 6) and Rondônia (n = 4) were submitted to RT-PCR in order to obtain partial sequences of nucleoprotein (N) and glycoprotein gene (G). Nucleotide sequences were analyzed using Neighbor-Joining model, Kimura 2-parameters evolutionary model. All the 17 samples analyzed were related to cluster A, lineage associated with the hematophagous bat Desmodus rotundus. The phylogenetic analysis based on the N and G genes, suggests the presence of five sub-lineages (A1-A5), while G gene showed seven sub-lineages (A1-A7). In both phylogenies, sublineages A1 to A3 exhibit a similar composition and geographic distribution. Diverse composition of remaining groups of N and G gene is attributable to different sequences used in the alignments for each genomic region. Glycoprotein amino acid sequence showed molecular markers in sub-lineages A2, A3, A4 and A7. This information provides a better comprehension of molecular epidemiology of rabies, starting with the knowledge of viral lineages circulating in the Brazilian Amazon.

O presente trabalho visou estudar dez isolados de vírus da raiva de morcegos hematófagos e não-hematófagos do Estado do Rio de Janeiro em suas características genéticas quanto aos genes N e G. Além disso, estudou-se a resposta de camundongos vacinados com a vacina antirrábica produzida pela replicação da amostra Pitman-Moore em cultivo celular, frente ao desafio com estes isolados virais, utilizando-se um ensaio imunológico baseado no teste de potência NIH. A vacina antirrábica utilizada na imunização dos camundongos ofereceu proteção em mais de 80% dos camundongos vacinados com a diluição 1:5 da vacina, frente à maioria dos isolados. A análise filogenética do gene da proteína N apresentou um padrão de agregação dividido em variante de morcego hematófago e variante de morcego insetívoro, com todos os isolados de morcegos frugívoros Artibeus sp. tendo sido segregados com a variante característica de morcegos Desmodus rotundus. Foram observadas diferenças filogenéticas entre as variantes do vírus da raiva de morcego hematófago isoladas na Região Noroeste do Estado do Rio de Janeiro e aquelas isoladas nas Regiões Metropolitana e Sul do Estado. A substituição do resíduo ácido aspártico por ácido glutâmico na posição 118, encontradas na caracterização genética da proteína G dos isolados 704/97BR-DR e 151/98BR-DR, permite inferir que esta posição esteja relacionada à antigenicidade viral. Não foram observadas diferenças genéticas temporais entre os isolados estudados. A vacina antirrábica utilizada ofereceu proteção satisfatória contra a maioria dos isolados estudados.

O perfil patogênico de um vírus da raiva isolado de um morcego insetívoro Lasiurus ega foi comparado com o de vírus fixo de raiva (CVS/32) em hamster e camundongo, determinando os períodos de incubação e clínico, manifestação clínica e mortalidade. Os animais foram desafiados com 10 2,611-4,021 DL50 /0,05 mL do isolado de L. ega e 10 3,7- 4,7 LD50 /0,05 mL do CVS/32, usando as vias: intramuscular (IM), intradermica (ID), intranasal (IN) e abrasão epidermica (AE). A presença do antígeno viral foi confirmada pela prova de imunofluorescência direta. As porcentagens de mortalidade observadas com o isolado de L. ega foram as seguintes em hamster: 3,5% IM, 10,71% IN; em camundongo: 50.0% IM, 30.0% IN. A forma furiosa da doença foi predominante. As porcentagens de mortalidade observadas com o vírus CVS/32 em hamster foram as seguintes: 12.5% IM, 62.5% ID, 12.5% IN; em camundongo 100.0% IM, 70.0% ID, 10.0% IN. Com este vírus foi observada raiva paralitica. A via AE mostrou-se inadequada para induzir doença. O período de incubação foi de 5–7 dias para o CVS/32 e 11-16 dias para o isolado de L. ega, entre tanto os períodos clínicos oscilaram entre 4–7 dias para ambos os vírus. Varias substituições foram achadas em domínios antigênicos da glicoproteína: AI (posição 231), AII (34 – 42 e 198-200), domínio de fusão dependente de baixo pH (102–179), domínio da transmembrana (440–461) e resíduo 242. Esses vírus mostraram comportamentos biológicos distintos o que poderia estar ligados às substituições nos domínios antigênicos anteriormente descritos. | Pathogenic profile of a rabies virus isolated from an insectivorous bat Lasiurus ega was compared with a rabies fixed virus strain (CVS/32) in hamster and mouse. Incubation and clinical periods, clinical manifestation and death rates were compared. Challenge of hamsters with L. ega was performed using: 10 2,611-4,021 LD50 /0,05 mL;. For CVS were used 10 3,7- 4,7 LD50 /0,05 mL. Were tested intramuscular (IM), intradermal (ID), intranasal (IN), epidermal abrasion (EA) inoculation routes. Viral antigen in brains was confirmed by Direct Immunofluorescence Test. Mortality percentages observed with L. ega rabies virus isolate were the following in hamster: 3,5 % IM, 10,710% IN; in mice: 50.0% IM, 30.0% IN. Furious rabies was predominant. Mortality percentages observed with CVS/32 in hamster: 12.5% IM, 62.5% ID, 12.5% IN; in mice 100.0% IM, 70.0% ID, 10.0% IN. Paralytic rabies was found with this strain in both animal models. Epidermic abrasion was not a suitable challenge route. Incubation period was 5-7 days for CVS and 11-16 days for L. ega isolate, meanwhile clinical periods were comprehended between 4–7 days for both viruses. Several substitutions were detected at antigenic domains of glycoprotein: AI (position 231), AII (34–42 and 198-200), domain of fusion dependent on low pH (102–179), transmembrane domain (440–461) and residue 242. These viruses showed contrasting biological behaviors that can be linked to those substitutions at antigenic domains previously described.