The Gunma Prefectural Institute of Public Health and Environmental Sciences strengthened laboratory services for influenza virus isolation. Following are preliminary results virus isolation. MDCK cell is employed for virus isolation, and the virus is identified by routine methods. The other specimens are not identified yet. Main symptoms of those isolated cases at the initial consultation include fever to 38C, upper respiratory tract inflammation, muscle and joint pain.
Some cases present lower respiratory tract inflammation, convulsion, and paralysis, also.
A 72 years old man presented one of the most characteristic cases. He developed fever, muscle pain, and dehydration, and he was hospitalized. Symptoms improved by the Day 10. Further virological investigation has been carried out against other influenza cases with similar symptoms. Virological investigation has been conducted for 19 outbreak incidences at school and social welfare facilities.