Relationship of Influenza Virus Infection and Complications from Viral/Bacterial Infections in a Community Based Setting

Rationale: Influenza virus is a major health care burden and is associated with significant morbidity and mortality. Data on morbidity and complications (pneumonia, otitis media, conjunctivitis, tonsillitis, enteritis) due to influenza virus infection in primary care settings are limited with reports mainly obtained from hospital settings.  We assessed the prevalence of complications from viral/bacterial infections in influenza- positive compared with influenza- negative children presenting with influenza-like illness (ILI) in a primary care setting.  

Methods: This retrospective, practice-based chart review studied complications from viral/bacterial infections in 255 children and adolescents (females/males, 1-21 years) who presented with ILI.  We also compared the prevalence of complications by influenza vaccination status between influenza positive and influenza negative cases (2013-2015). Comparisons for categorical variables were made using chi-squared tests.

Results:  The prevalence of complications (pneumonia, otitis media, conjunctivitis, enteritis) was similar in influenza positive and influenza negative patients (P=NS), with the exception of tonsillitis, which was more common in patients who tested positive for Influenza B (P=0.015).  Patients who were vaccinated were less likely to test positive for influenza compared with patients who were not vaccinated (P=0.064). However, prevalence of infections was similar in both groups based on vaccination status.

Conclusions: In a primary care setting, complications from viral/bacterial infections did not differ in influenza positive compared with influenza negative patients. Vaccination with influenza vaccine may result in decreased duration or severity of symptoms and remains an important public health intervention.