Respiratory Viral Coinfection More Common in Children Than Adults

Young mother squeezing hand sanitizer onto little daughter’s hand in the playground to prevent the spread of viruses
Respiratory viral coinfection occurs substantially more frequently in children, especially in those aged <5 years.

Compared with adults, respiratory viral coinfection occurs substantially more frequently in children, especially in children aged <5 years, according to study results published in Clinical Microbiology and Infection.

To determine if certain viral species are predisposed to coinfection and to identify those viral pairings occurring at frequencies different than expected based on pathogen co-circulation within the community, researchers performed a cross-sectional analysis of respiratory viral panel results obtained from children and adults at the Cleveland Clinic in Ohio from November 30, 2013, through June 6, 2018. The GenMark Xt-8 System (GenMark Diagnostics, Inc., Carlsbad, California) was used to identify viral pathogens. Employing a model to proportionally distribute viral pairs using individual virus’ coinfection rate with prevalence patterns of concurrent co-circulating viruses, the researchers compared predicted to observed occurrences of 132 viral pairing permutations using binomial analysis.

Of the 9407 specimens evaluated (52.6% from children) that were positive for at least 1 viral pathogen, 1018 (10.8%) were identified as having more than one viral pathogen: 93.6% had one additional pathogen and 6.4% had 2 or more. Coinfection was significantly more common in children compared with adults (18.0% [891/4947] vs 2.8% [127/4460], respectively; P <.001). The median age of children with coinfection was 13 months vs a median age of 59 years for adults.

In both children and adults, the highest coinfection rate was seen for adenovirus C at 68.4% (426/623), while the lowest coinfection rate was seen for influenza B virus at 10.7% (55/546). Significantly lower coinfection rates were seen for influenza viruses and human metapneumovirus compared with other viral strains. Rhinovirus was the most common viral infection identified and was associated with the most coinfections overall. Although rhinovirus had a high coinfection rate in children at 33.3% (742/2226), its coinfection rate in adults was only 5% (88/1760).

The following pairings occurred at significantly higher frequencies than predicted by the proportional distribution model: adenovirus C and rhinovirus, respiratory syncytial virus A and rhinovirus, and respiratory syncytial virus B and rhinovirus. Additionally, several viral pairings had fewer coinfections than predicted by the model: notably human metapneumovirus and parainfluenza virus 3, human metapneumovirus and respiratory syncytial virus A, and respiratory syncytial virus A and respiratory syncytial virus B.

A key limitation of this study was that the Genmark platform used does not detect certain viruses commonly associated with coinfection like coronavirus, enterovirus, and bocavirus. “The worldwide spread of [severe acute respiratory syndrome coronavirus 2] exemplifies the need to increase our understanding of virus-virus interactions involving coronaviruses,” stressed the authors.

Disclosure: Sandra S. Richter, MD, and Frank Esper, MD, declared affiliations with the pharmaceutical industry. Please see the original reference for a full list their disclosures.


Mandelia Y, Procop GW, Richter SS, Worley S, Liu W, Esper F. Dynamics and predisposition of respiratory viral co-infections in children and adults [published online June 12, 2020]. Clin Microbiol Infect. doi:10.1016/j.cmi.2020.05.042