Respiratory Virus Infection and Risk of Invasive Meningococcal Disease in Central Ontario, Canada

Laura M Kinlin,David N Fisman,Ashleigh R Tuite,Stefan P Kuster,Jeffrey C Kwong,Allison Mcgeer,Frances Jamieson,Benjamin J Cowling

doi:10.1371/journal.pone.0015493

Abstract

BackgroundIn temperate climates, invasive meningococcal disease (IMD) incidence tends to coincide with or closely follow peak incidence of influenza virus infection; at a seasonal level, increased influenza activity frequently correlates with increased seasonal risk of IMD.MethodsWe evaluated 240 cases of IMD reported in central Ontario, Canada, from 2000 to 2006. Associations between environmental and virological (influenza A, influenza B and respiratory syncytial virus (RSV)) exposures and IMD incidence were evaluated using negative binomial regression models controlling for seasonal oscillation. Acute effects of weekly respiratory virus activity on IMD risk were evaluated using a matched-period case-crossover design with random directionality of control selection. Effects were estimated using conditional logistic regression.ResultsMultivariable negative binomial regression identified elevated IMD risk with increasing influenza A activity (per 100 case increase, incidence rate ratio = 1.18, 95% confidence interval (CI): 1.06, 1.31). In case-crossover models, increasing weekly influenza A activity was associated with an acute increase in the risk of IMD (per 100 case increase, odds ratio (OR) = 2.03, 95% CI: 1.28 to 3.23). Increasing weekly RSV activity was associated with increased risk of IMD after adjusting for RSV activity in the previous 3 weeks (per 100 case increase, OR = 4.31, 95% CI: 1.14, 16.32). No change in disease risk was seen with increasing influenza B activity.ConclusionsWe have identified an acute effect of influenza A and RSV activity on IMD risk. If confirmed, these finding suggest that influenza vaccination may have the indirect benefit of reducing IMD risk.

Highlights

Neisseria meningitidis is a leading cause of meningitis and bacteremia worldwide [1]
This association has led some investigators to suggest that influenza activity may directly influence invasive meningococcal disease risk [10], but evidence for acute effects of changing influenza activity on invasive meningococcal disease risk has to date been limited
Submission date and disease outcome were ascertained from patient requisitions and electronic databases used for the reporting of notifiable diseases in Ontario: the Reportable Disease Information System (RDIS) (2000–2005) and the integrated Public Health Information System (2006)

Summary

Introduction

Neisseria meningitidis is a leading cause of meningitis and bacteremia worldwide [1]. Other seasonal exposures have been postulated to drive the seasonality of IMD: surges in IMD activity frequently coincide with or closely follow increases in the incidence of influenza and other respiratory virus infections [10,11,12,13], with elevated IMD risk reported when influenza activity is ‘‘epidemic’’ [14] This association has led some investigators to suggest that influenza activity may directly influence invasive meningococcal disease risk [10], but evidence for acute effects of changing influenza activity on invasive meningococcal disease risk has to date been limited. Invasive meningococcal disease (IMD) incidence tends to coincide with or closely follow peak incidence of influenza virus infection; at a seasonal level, increased influenza activity frequently correlates with increased seasonal risk of IMD

Methods

Results

Conclusion