Epidemic Status of Influenza Virus between 2004-2005 and 2005-2006 at Kawasaki Medical School Hospital

Abstract

Of patients with influenza-like symptoms such as fever, myalgia and arthralgia 2399 visited Kawasaki Medical School Hospital in 2004-2005 and 2171 in 2005-2006. Among those patients over 16 years old, laboratory examinations using the rapid antigen test or the serum HI test were positive for 366 (A: 86, B: 280) in 2004-2005 and 372 (A: 370, B: 2) in 2005-2006. Influenza B achieved epidemic status first in 2004-2005, followed by influenza A (H3N2) after April 2005. Only influenza A was epidemic in 2005-2006. The slight difference in frequency or complication between these strains was not statistically significant. In spite of influenza vaccination inoculation in 20% of patients with influenza in 2004-2005 and 2005-2006, influenza spread. The prognosis of these patients, however, was comparatively good.