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H Artsob

Publications and source records attributed to H Artsob.

62 records · Page 4Linked to original sources

St. Louis encephalitis in southern Ontario: laboratory studies for arboviruses.

The first reported outbreak of St. Louis encephalitis in Canada occurred in the summer of 1975 in southern Ontario -- in the Windsor-Sarnia-Chatham area, the Niagara region and the city of Toronto. Hemmagglutination inhibition and complement fixation testing of serum samples collected during the outbreak confirmed that St. Louis encephalitis virus was the etiologic agent. Furthermore, this virus was isolated from brain tissue of a patient who died. This outbreak was probably an extension of the outbreak that occurred in the United States that summer. It was the first outbreak of arbovirus encephalitis in the province of Ontario.

Antibodies, Viral↗

Immune electron microscopy of arboviruses.

Representative members of four arbovirus taxons were studied by immune electron microscopy (IEM) in an attempt to determine whether the technique can be applied to the specific identification of arboviruses. Alphavirus, flavivirus, bunyavirus, and rhabdovirus antigens were prepared by propagation in tissue culture. The viruses were used to titrate homologous antibody and test heterologous antibody in the IEM test. Specific clumping together with visualization of antibody attachment was observed for all homologous systems studied. For the alphaviruses, titers of antibody, as determined by IEM, were comparable with the titers obtained by hemagglutination inhibition. Alphavirus cross-reactions were observed at low antibody dilutions by IEM. However, further dilution of antibody resulted in specific clumping only of homologous virus, allowing specific identification of alphavirus unknowns. For all viruses studied, positive IEM reactions were obtained with homologous grouping ascitic fluids but not with heterologous grouping fluids.

Antibodies, Viral↗

Arboviruses as aetiological agents of encephalitis in the People's Republic of China.

A serological study was undertaken to determine the role of arboviruses as etiological agents of encephalitis in the People's Republic of China (PRC). Paired sera were collected during mosquito seasons in 1988-1990 from 614 patients with possible viral encephalitis in 15 regions of PRC and tested for haemagglutination inhibiting antibodies to selected arboviruses. Seroconversions were documented to alphavirus and flavivirus antigens in 13.0 and 18.7% of patients respectively in most of the study areas. No California group seroconversion was detected. The age of alphavirus seroconvertors ranged from 2 months to 32 years and of flavivirus seroconvertors from 6 months to 50 years, with higher numbers in males. Serious central nervous system manifestations were seen more commonly in flavivirus seroconvertors. This study affirms the importance of flavivirus as causative agents of encephalitis in PRC and provides evidence that one or more alphaviruses are causing symptomatic infections with neurological involvement in PRC.

Adolescent↗

Genetic diversity and distribution of Peromyscus-borne hantaviruses in North America.

The 1993 outbreak of hantavirus pulmonary syndrome (HPS) in the southwestern United States was associated with Sin Nombre virus, a rodent-borne hantavirus; The virus' primary reservoir is the deer mouse (Peromyscus maniculatus). Hantavirus-infected rodents were identified in various regions of North America. An extensive nucleotide sequence database of an 139 bp fragment amplified from virus M genomic segments was generated. Phylogenetic analysis confirmed that SNV-like hantaviruses are widely distributed in Peromyscus species rodents throughout North America. Classic SNV is the major cause of HPS in North America, but other Peromyscine-borne hantaviruses, e.g., New York and Monongahela viruses, are also associated with HPS cases. Although genetically diverse, SNV-like viruses have slowly coevolved with their rodent hosts. We show that the genetic relationships of hantaviruses in the Americas are complex, most likely as a result of the rapid radiation and speciation of New World sigmodontine rodents and occasional virus-host switching events.

Animals↗