title: Recurrence and persistence of fever in children who developed amantadine-resistant influenza viruses after treatment.
abstract: In recent years, a dramatic increase of amantadine-resistant influenza A has occurred globally, but limited data have been available on the clinical course of patients developed amantadine-resistant viruses. We compared fever reduction between patients who developed resistance or remained sensitive in a pediatric clinic in Niigata, Japan, from 2000 to 2006. A total of 2,802 clinical samples were collected from patients who visited the pediatric outpatient clinic with influenza like illness during the seven influenza epidemic seasons. Patients were divided into 4 groups and analyzed for the fever reduction after amantadine treatment: emerged amantadine-resistant (n = 15); amantadine-sensitive (n = 35); patients administered no antiviral drugs (n = 42); and oseltamivir-treated patients (n = 320), which served as references. All 4 groups showed alleviation of fever up to day 3. The amantadine-resistant group had a significant recurrence of fever on day 4 and/or 5, and as a consequence, the course of illness was prolonged. Considering the pattern of fever, recurrent and persistent patterns were found significantly at higher rates in children with emerged resistant virus compared to other groups, and the age tended to be younger in amantadine-resistant compared to amantadine-sensitive group (3.9 +/- 3.0 vs 6.7 +/- 4.1 years old, n.s.). Therefore, we concluded that younger children were prone to develop amantadine-resistance after treatment and showed a significant recurrence of fever on day 4 and/or 5, and the course of illness was consequently prolonged.
authors.affiliation: Department of Public Health, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan. yugo@med.niigata-u.ac.jp
authors.forename: Yugo
authors.initials: Y
authors.lastname: Shobugawa
authors.forename: Reiko
authors.initials: R
authors.lastname: Saito
authors.forename: Isamu
authors.initials: I
authors.lastname: Sato
authors.forename: Danjuan
authors.initials: D
authors.lastname: Li
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Asami
authors.initials: A
authors.lastname: Sasaki
authors.forename: Maki
authors.initials: M
authors.lastname: Sato
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suzuki
mesh_terms: D000547:Amantadine / Q000494:pharmacology* / Q000627:therapeutic use*; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D001831:Body Temperature / Q000187:drug effects; D002675:Child, Preschool; D003710:Demography; D004285:Dogs; D024882:Drug Resistance, Viral / Q000187:drug effects*; D005260:Female; D005334:Fever / Q000188:drug therapy* / Q000517:prevention & control; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects*; D008297:Male; D012008:Recurrence
chemical_list: D000998:Antiviral Agents; D000547:Amantadine