Isolation of influenza A(H1) virus from an influenza outbreak at a primary school, January 2001 - Fukui
(IASR 2001; 22: 59-60)
On January 24, 2001, an influenza outbreak occurred at a primary school in Obama City, the southern part of Fukui Prefecture. Throat garglings were inoculated onto MDCK cells, and 3 out of 6 patients were positive for influenza virus A/H1. Hemaggulutination inhibition (HI) tests showed an HI titer of 1:320 (the same as the homo-titer) for A/New Caledonia/20/99 (H1N1), which was employed as a current vaccine strain. The strain used in our assays was provided by NIID.
Major symptoms included fever (38.5-39.5C), headache, runny nose, cough, sore throat, and some patients presented with diarrhea and other gastrointestinal symptoms. During the outbreak, 14 out of 32 pupils of a grade 6 class (11-12 years of age) were absent from school and the class was closed for a few days.
To date, in Fukui Prefecture, this is the only incident in which influenza virus was isolated and identified. Monitoring is being continued.
Reported by: Yukinori Arisada and Kazuo Matsumoto, Fukui Prefectural Institute of Public Health
Correspondence: Yukinori Arisada;
E-mail: y-arisada-56@ain.pref.fukui.jp
FAX: +81-776-52-1609