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Fluorescence-based Neuraminidase Inhibition Assay to Assess the Susceptibility of Influenza Viruses to The Neuraminidase Inhibitor Class of Antivirals

Fluorescence-based Neuraminidase Inhibition Assay to Assess the Susceptibility of Influenza Viruses to The Neuraminidase Inhibitor Class of Antivirals

Published on: April 15, 2017

Frequency and effects of bacterial infection in children with influenza under oseltamivir treatment

Keiko Ninomiya¹, Naoki Madenokouji, Miharu Hajikano

¹Department of Pediatrics, Nissan Tamagawa Hospital, Tokyo, Japan. info@tamagawa-hosp.jp

Journal of Nippon Medical School = Nippon Ika Daigaku Zasshi

|June 23, 2006

Abstract

Background:

New antiviral drugs can rapidly improve the symptoms of influenza, but some patients still have prolonged fever and complications. The cause of the prolonged symptoms despite antiviral therapy remains unclear. Recent studies have shown a synergistic effect between influenza viruses and bacteria. This study investigated the frequency of bacterial infection in such patients and its effects on the clinical course to determine the need for antibiotics.

Methods:

In two seasons (December 2001 through March 2002, and December 2002 through March 2003), throat cultures were obtained from 387 patients with influenza being treated with oseltamivir, and clinical courses were observed. Control throat cultures were obtained from 109 healthy children.

Results:

The detection rate of pathogens was higher in patients with influenza (54.3%) than in control (23.9%, p<0.001). The most common pathogen was Streptococcus pneumoniae (49.7%) in patients with influenza and was Haemophilus influenzae (69.2%) in controls. Of the patients with normal flora, 4.1% had fever for 4 or more days and showed pathogens in throat cultures on day 4. Of the patients with pathogen-positive cultures who did not receive antibiotics, 40.3% had fever for 4 or more days.

Conclusion:

Throat cultures obtained on the first or fourth day of treatment with oseltamivir were positive for pathogenic bacteria in all patients with fevers for 4 or more days. Our observations suggest that patients with influenza and prolonged fever despite receiving oseltamivir should be given antibiotics.

Insights

Patients with influenza treated with oseltamivir often develop bacterial infections, leading to prolonged fever. Prompt antibiotic treatment is recommended for influenza patients experiencing persistent fevers despite antiviral therapy.

Area of Science:

Infectious Diseases
Microbiology
Clinical Medicine

Background:

Influenza antiviral drugs improve symptoms, but prolonged fever and complications persist in some patients.
The cause of persistent symptoms despite antiviral therapy is unclear, with potential synergistic effects between influenza viruses and bacteria.
This study investigates bacterial infection frequency and its impact on clinical course in influenza patients to assess the need for antibiotics.

Purpose of the Study:

To determine the frequency of bacterial infections in influenza patients receiving oseltamivir.
To evaluate the effect of bacterial infections on the clinical course of influenza, specifically prolonged fever.
To provide evidence for the necessity of antibiotic treatment in specific influenza patient groups.

Main Methods:

Throat cultures were collected from 387 influenza patients treated with oseltamivir over two seasons (2001-2003).
Clinical courses of influenza patients were observed, focusing on fever duration and complications.
Control throat cultures were obtained from 109 healthy children for comparison.

Main Results:

Pathogen detection rates were significantly higher in influenza patients (54.3%) compared to controls (23.9%).
Streptococcus pneumoniae was the most common pathogen in influenza patients (49.7%), while Haemophilus influenzae was prevalent in controls (69.2%).
Patients with pathogen-positive cultures who did not receive antibiotics had a 40.3% rate of fever lasting 4 or more days.

Conclusions:

Pathogenic bacteria were detected in throat cultures of all influenza patients with fevers lasting 4 or more days, even when treated with oseltamivir.
These findings suggest a significant role for bacterial coinfection in prolonged fever during influenza.
Antibiotic administration is recommended for influenza patients experiencing prolonged fever despite oseltamivir treatment.

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