Publications by authors named "Keiji Sahara"
Article Synopsis
- In February 2015, a rubella outbreak was reported in Shizuoka, Japan, starting with two cases from the same company, leading to collaboration between local health departments and the National Institute of Infectious Diseases to investigate the situation.
- The outbreak was linked to three companies, resulting in a total of 25 cases (17 confirmed and 8 probable), predominantly affecting unvaccinated male employees with a median age of 45.
- Genetic analysis of the rubella virus indicated it was a single strain (genotype 1E) likely imported from Southeast Asia, highlighting vaccination gaps in small- and medium-sized businesses in the region.
Influenza A and B viruses possess a neuraminidase protein that shows sialidase activity. Influenza virus-specific neuraminidase inhibitors (NAIs) are commonly used for clinical treatment of influenza. However, some influenza A and B viruses that are resistant to NAIs have emerged in nature.
View Article and Find Full Text PDFTo characterize Japanese encephalitis virus (JEV) strains recently prevalent in Japan, JEV surveillance was performed in pigs from 2002 to 2004. Eleven new JEV isolates were obtained and compared with previous isolates from Japan and other Asian countries. All of the isolates were classified into genotype 1 by nucleotide sequence analysis of the E gene.
View Article and Find Full Text PDFEffects of host-cell adaptation of the hemagglutinin (HA) protein were evaluated by the analyses of four pairs of recent influenza B field isolates, each pair consisting of an Madin Darby canine kidney (MDCK)- and an embryonated chicken egg-derived isolates from the same clinical specimen. Among the isolates examined, all of the MDCK-derived isolates retained glycosylation site at amino acid 197 on the HA1 molecule, whereas three egg-derived isolates lost it. Antigenic difference in the HA molecule between an MDCK- and an egg-derived isolates of three of these pairs was demonstrated to be associated with the glycosylation 197.
View Article and Find Full Text PDF(1) Seroepidemiological analysis of influenza pandemics (1986-2003) in Shizuoka Prefecture and all Japan revealed differences in geographical, annual, seasonal, and age distributions. (2) For 17 years, the pandemics generally began at the 50th week every year showing over 1.0 patient/clinic, reached the peak at 5th week the following year, and ended over 10-15th week.
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