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PubMed2001

Antigenic properties and experimental transmission to several fish species of a marine birnavirus isolated from sole (Solea senegalensis).

A cross-neutralization test was used to study the antigenic relationship of an aquabirnavirus isolated from sole (Solea senegalensis), named solevirus, and several infectious pancreatic necrosis virus (IPNV) strains. Solevirus was antigenically similar to IPNV strain Sp. Transmission of the solevirus to other fish species has been determined by inoculation to freshwater and marine fish species (two salmonids and gilt-head seabream). A higher pathogenicity was obtained for the marine fish species, although solevirus caused an asymptomatic infection in all species tested, as demonstrated by the detection of viral RNA and of viral antigens in fish leucocytes, respectively, using polymerase chain reaction (PCR) and flow cytometry (FC).

Animals↗
PubMed1999

Lesions and transmission of experimental adenovirus hemorrhagic disease in black-tailed deer fawns.

Adenovirus infection was the cause of an epizootic of hemorrhagic disease that is believed to have killed thousands of mule deer (Odocoileus hemionus) in California during the latter half of 1993. A systemic vasculitis with pulmonary edema and hemorrhagic enteropathy or a localized vasculitis associated with necrotizing stomatitis/pharyngitis/glossitis or osteomyelitis of the jaw were common necropsy findings in animals that died during this epizootic. To study transmission of adenovirus infection in deer and susceptibility of black-tailed deer (Odocoileus hemionus columbianus) fawns to adenovirus infection, six 3-6-month-old black-tailed fawns were divided into two treatment groups. One group was inoculated intravenously and the other group was inoculated through the mucous membranes of the eyes, nose and mouth with purified adenovirus. Each treatment group also included two additional fawns (four total) that were not inoculated but were exposed to inoculated animals (contact animals). One fawn served as a negative control. Between 4 and 16 days postinoculation, 8/10 fawns developed systemic or localized infection with lesions identical to lesions seen in animals with natural disease that died during the epizootic. Transmission was by direct contact, and the route of inoculation did not affect the incubation period or the distribution of the virus (systemic or the localized infection). Immunohistochemical analysis using polyclonal antiserum against bovine adenovirus type 5 demonstrated staining in endothelial cells of vessels in numerous tissues in animals with systemic infection and endothelial staining only in vessels subtending necrotic foci in the upper alimentary tract in animals with the localized form of the disease. All inoculated or exposed animals had staining in the tonsillar epithelium. Transmission electron microscopic examination of lung and ileum from two fawns with pulmonary edema and hemorrhagic enteropathy demonstrated endothelial necrosis and adenovirus virions in endothelial cell nuclei. Adenovirus was reisolated in black-tailed deer pulmonary artery endothelial cells using lung homogenate of the first fawn that developed systemic adenovirus infection. Serum virus neutralization test results suggest that this deer adenovirus is a new serotype.

Adenoviridae Infections↗
PubMed1995

Persistence of a single electropherotype and serotype (G6P5) of bovine rotavirus in calves on a closed dairy farm from 1990 to 1993.

A virologic survey was conducted on calves with diarrhea associated with bovine rotavirus (BRV) on a closed dairy farm. The BRV was detected from 32 of 219 (14.6%) fecal specimens repeatedly collected from 56 calves born during the years 1992-1993, regardless of whether they had diarrhea. Most of the 32 strains were isolated from fecal specimens obtained from 2- to 6-week-old calves. After electrophoresis of double-stranded viral RNA from the 32 strains, genomic RNA migration patterns were similar to those of the predominant BRV strains isolated at the same farm during the years 1990-1991. All representative strains were identified as G serotype 6 (G6) and P type 5 (P5) by results of the virus-neutralization test and polymerase chain reaction procedure. Thus, BRV had no change in genomic RNA electropherotypes and serologic antigenicities in a closed dairy herd over a period of several years.

Animals↗
PubMed1986

[Status of immunity against poliomyelitis in Germany].

Neutralizing antibodies against poliovirus types 1, 2 and 3 were determined in serum of 4,039 persons of different ages and of 879 persons at the beginning of their training (male recruits at their initial examination; female teaching trainees and student nurses). The sera were supplied by eleven institutions. Compared with similar studies in 1969, 1972 and 1978, the immunity against individual poliovirus types as well as that against the three types in the different age groups has improved. About three quarters of those older than seven years have antibodies against types 1, 2 and 3. The present study, which for the first time used a more sensitive neutralization test, revealed that about 85% of probands had antibodies against all three types. The trivalent immunity of those aged from 0 to six years has improved by 11 percent points since 1978. There was no decrease in immunity among those older than 20 years.

Adolescent↗
PubMed1977

Laboratory characteristics of poxviruses isolated from captive elephants in Germany.

Proxviruses isolated from captive elephants in Germany have been characterized. Although related to vaccinia and even more closely to cowpox virus, the separate identity of elephantpox virus was established by both biological and serological methods. Elephantpox virus produces A-type inclusions in infected cells, as did cowpox, but had a lower ceiling temperature, was more heat resistant and affected rabbits differently. Cross neutralization tests on absorbed sera indicated that elephantpox, cowpox and vaccinia viruses shared one surface antigen, that elephantopox and vaccinia shared an antigen absent from cowpox, and that vaccinia virus had a surface antigen absent from elephantopox and cowpox viruses.

Animals↗
PubMed1988

Monoclonal antibody enzyme-linked immunosorbent assay for specific identification and typing of subgroup F adenoviruses.

Monoclonal antibody specific for subgroup F enteric adenoviruses (EAds) was prepared by fusing P3-NS1/Ag4-1 mouse myeloma cells with lymphocytes from BALB/c mice immunized with G1105, an adenovirus type 41 (Ad41) strain. Monoclone 3F11/2H9, which specifically recognized Ad41, was successfully used as detector antibody in an enzyme-linked immunosorbent assay (ELISA). Additionally, previously prepared monoclones 5D8/2C2 and 2H6/1E11, recognizing Ad40 plus Ad41 and Ad40 alone, respectively, were used to study stool and/or tissue culture specimens from 106 patients with adenovirus-positive gastroenteritis. By ELISA, 91 had EAds (22 were Ad40 and 69 were Ad41) and 15 had non-EAds. ELISA results were in concordance with restriction endonuclease results for 38 of 39 specimens, with dot blot data for 19 of 20 specimens, and with neutralization test results for 74 of 78 specimens. ELISA was at least 10-fold more sensitive than direct electron microscopy was for the detection of EAds in stool specimens.

Acute Disease↗
PubMed1982

Bovine herpes mammillitis in two New York dairy herds.

Bovine herpes mammillitis was diagnosed in 2 New York dairy herds. Lesions ranged from vesiculation and ulceration of large (up to 10 cm wide) areas of udder and teat skin to single small (2-3 cm wide) plaques of edema. Some lesions resembled "umbilicated pocks" characteristic of cowpox virus infections. Recently freshened heifers were the most severely affected; older cows and heifers with less turgid udders had milder lesions. In 2 cows, incurable mastitis developed. In other cows, the lesions healed by centripetal growth of epidermis into the lesions. Diagnosis was made by isolation of bovid herpesvirus 2 from lesions in both herds and by serum-neutralization testing. Virus isolated from a cow in 1 herd was injected into 9 members of the same herd and may have been responsible for the absence of lesions on these animals; all other members of the herd were affected.

Animals↗
PubMed1999

Genetic and antigenic diversity among eastern equine encephalitis viruses from North, Central, and South America.

Eastern equine encephalitis virus (EEEV), the sole species in the EEE antigenic complex, is divided into North and South American antigenic varieties based on hemagglutination inhibition tests. Here we describe serologic and phylogenetic analyses of representatives of these varieties, spanning the entire temporal and geographic range available. Nucleotide sequencing and phylogenetic analyses revealed additional genetic diversity within the South American variety; 3 major South/Central American lineages were identified including one represented by a single isolate from eastern Brazil, and 2 lineages with more widespread distributions in Central and South America. All North American isolates comprised a single, highly conserved lineage with strains grouped by the time of isolation and to some extent by location. An EEEV strain isolated during a 1996 equine outbreak in Tamaulipas State, Mexico was closely related to recent Texas isolates, suggesting southward EEEV transportation beyond the presumed enzootic range. Plaque reduction neutralization tests with representatives from the 4 major lineages indicated that each represents a distinct antigenic subtype. A taxonomic revision of the EEE complex is proposed.

Amino Acid Sequence↗
PubMed1991

Production of monoclonal antibodies against a hemagglutinin/protease of Vibrio cholerae non-01.

Two hybridoma cell lines producing monoclonal antibodies (MAbs) against a hemagglutinin/protease (HA/P) from Vibrio cholerae non-01 were produced and characterized. The two MAbs contained the kappa light chain and were IgG1 type. They similarly neutralized HA/P protease activity derived from both V. cholerae non-01 and V. cholerae 01, whereas they were unable to neutralize the hemagglutinating activity of HA/P, suggesting that the epitopes for protease and hemagglutination activities are different. Western blotting analysis and the cross-neutralization test with the two MAbs confirmed the identity of HA/P produced by V. cholerae non-01 and 01. This study also suggests that HA/P of V. cholerae and a protease of V. parahaemolyticus are immunologically unrelated.

Animals↗
PubMed1997

The characterization of infectious bursal disease virus strains/isolates from field outbreaks in India.

Three infectious bursal disease virus (IBDV) isolates were adapted to culture in chick embryo fibroblast cells in which they produced a cytopathic effect. The isolates were identified as IBDV by virus neutralization tests using a standard hyperimmune serum against infectious bursal disease, physicochemical properties and their pathogenicity in chick embryos and chicks. The IBDV S394 strain was antigenically different from IBDV S194/IBDV S494 as well as from the IBDV Intermediate Georgia strain, one of the vaccine strains in use in India.

Animals↗
PubMed1979

Characterization of a virus isolated from a case of human infectious hepatitis.

A new viral agent, isolated from the serum of an infectious hepatitis patient and designated as Agent II-B, was extensively studied in in vitro and in vivo systems. Agent II-B multiplied well in primary and serial animal cell cultures and in embryonated hen's eggs. Quantal and quantitative infectivity assays were performed in monolayers of African green monkey kidney cells. Effective concentrations of 5-iodo-2-deoxyuridine and guanidine hydrochloride did not inhibit the multiplication of Agent II-B, although 2-hydroxybenzyl-benzimidazole was an effective inhibitor. Essential lipids were not detected. The diameter of the agent is 16-25 nm and its buoyant density in CsCl equilibrium density gradients was 1.35 gm/ml. Neutralization test results did not reveal antigenic relatedness between Agent II-B and known human picornaviruses. Apparently, this new viral agent is a picornavirus which possesses the capacity to multiply in unexpectedly diverse cell types.

Benzimidazoles↗
PubMed1990

Disseminated adenovirus (type 19) infection in a neonate. Rapid detection of the infection by immunofluorescence.

A case of fatal disseminated adenovirus infection in a neonate who suffered from severe keratoconjunctivitis and pneumonitis is reported. The diagnosis was made seven days after the onset of illness based on the detection of adenovirus antigen in the smears of the tracheal suction and conjunctival swab by immunofluorescence. Viral antigen was detected in the frozen or formalin-fixed autopsy specimens of the lungs, kidneys, spleen, liver and lymph nodes. Typical crystal arrangement of adenovirus virions was observed in the alveolar epithelial cells by electron microscopy. The isolated virus was identified to be of type 19 by a neutralization test. The IF examination using adenovirus group specific immune reagents on the smears of clinical specimens appears to be useful for rapid diagnosis of viral infections.

Adenoviridae Infections↗
PubMed1987

Immunological relation between serum antibodies against pneumolysin and against streptolysin O.

The immunological relation between serum antibodies to pneumolysin and to streptolysin O was studied in patients with pneumococcal pneumonia (n = 40), patients with infections due to beta-haemolytic streptococci (n = 35), healthy human controls (n = 60) and in rabbits immunized with pneumolysin. There was no correlation between anti-pneumolysin and anti-streptolysin O titers (r = -0.279). The distribution of anti-pneumolysin titers in patients with high anti-streptolysin O titers did not differ from healthy controls. However, there was a tendency to increased or rising anti-streptolysin O titers in patients with pneumococcal infection. Antibodies obtained during pneumococcal infection might thus give false-positive reactions in the streptolysin O neutralization test. Serum antibodies to streptolysin O do not cross-react with pneumolysin in an ELISA. The pneumolysin ELISA for detection of pneumococcal disease will therefore not be disturbed by false-positive reactions due to antibodies directed against beta-haemolytic streptococci.

Animals↗
PubMed1991

Molecular and antigenic analyses of serotypes 8 and 10 of bovine rotaviruses in Thailand.

Antigenic and genomic properties of non-serotype 6 bovine rotaviruses isolated in Thailand and Japan were studied by cross-neutralization tests, nucleotide sequence determination of the VP7 gene, and RNA-RNA hybridization. Two Thai strains (61A and A44) were serologically related to a Japanese isolate KK3 which has been assigned to serotype 10. In contrast, strain A5 was found to be antigenically similar to human strain 69M with serotype 8 specificity, although strain A5 showed a one-way cross-reaction with serotype 6 strain NCDV. VP7 sequence analysis confirmed these results. High degrees of similarity in nucleotide and amino acid sequences (92.5 to 98.2% and 96.3 to 97.9%, respectively) were found among the VP7 genes of the four serotype 10 bovine strains (61A, A44, KK3 and B223). The VP7 amino acid sequence of strain A5 was similar to those of serotype 8 human strains (91.7% and 94.8% for strains B37 and 69M, respectively). In RNA-RNA hybridization experiments, a high level of overall relatedness was found among the three serotype 10 bovine strains (61A, A44 and KK3), and strains A5 and NCDV were also moderately related to the three serotype 10 viruses. All the bovine rotaviruses tested in this study, regardless of their serotype specificity, exhibited a moderate genetic-relatedness to strain 69M of serotype 8, and, to a lesser extent, to serotype 2 human rotavirus strains.

Amino Acid Sequence↗
PubMed2004

Healthcare worker seroconversion in SARS outbreak.

Serum samples were obtained from healthcare workers 5 weeks after exposure to an outbreak of severe acute respiratory syndrome (SARS). A sensitive dot blot enzyme-linked immunosorbent assay, complemented by a specific neutralization test, shows that only persons in whom probable SARS was diagnosed had specific antibodies and suggests that subclinical SARS is not an important feature of the disease.

Antibodies, Viral↗
PubMed1993

Epizootiological study of hantavirus infection among Rattus norvegicus in Tokyo Bay area, Japan.

The prevalence of antibodies against hantavirus in 413 rats (Rattus norvegicus) captured in eight regions of the Tokyo Bay area from 1983 to 1992 were examined by the indirect fluorescent antibody test. Antibody-positive rats were found in Tokyo Port in 1983 (34.8%), 1984 (25.9%), 1985 (22.0%) and 1986 (15.6%), in Kasai Seaside Park in 1989 (3.2%) and 1990 (4.2%) and in Chiba Port in 1990 (6.7%). In Tokyo Port, antibody-positive rats were found in any season in 1984 and 1985, and seroprevalences among two age groups, i. e., less than six months and six or more months of age were 18.1% and 28.4%, respectively. Three virus strains were isolated from rats captured on reclaimed land No. 13 in Tokyo Port in 1985 and named TQR-23, TQR-48 and TQR-50. These strains were antigenically identical with other rat strains, e. g., strain SR-11 and TR-352 but were discriminated from 76-118 strain by the neutralization test. Until 1990, persistence of hantavirus among rats inhabiting the Tokyo Bay area was demonstrated and hantavirus may be continuously prevalent in rats in this area.

Animals↗
PubMed2000

New P serotype of group A human rotavirus closely related to that of a porcine rotavirus.

The VP7 and VP4 genes of two human group A rotavirus strains Mc323 and Mc345 with unique serologic and genomic properties, and isolated in Chiang Mai, Thailand, in 1989 [Urasawa et al. (1992) Journal of Infectious Diseases 166:227-234] were further characterized. The nucleotide and deduced amino acid sequences of the VP7 genes allowed the classification of both strains as serotype G9. The VP4 genes of both strains are 2,359 nucleotides in length and encode a protein of 775 amino acids like in most human rotaviruses. A comparison of the VP4 amino acid sequence of strain Mc323 with those of strain Mc345 and 24 human and animal rotaviruses representing 20 distinct VP4 genotypes reported to date showed that VP4 of Mc323 and Mc345 belong to genotype 19 previously reported for porcine rotavirus [Burke et al. (1994) Journal of General Virology 75:2205-2212]. To investigate the serological type (P serotype) of these VP4s, six reassortant viruses each containing a distinct VP4 gene characteristic of human rotaviruses and the VP7 gene of porcine rotavirus strain Gottfried (G4) were prepared, and antisera to these reassortants produced in rabbits. In neutralization tests, the P serotype of Mc323 was clearly differentiated from the five major P serotypes reported previously for human rotaviruses, suggesting that Mc323 and Mc345 represent a new human rotavirus P serotype tentatively called P11.

Amino Acid Sequence↗