This article is more than 5 years old. Information may no longer be current.

Viral coinfections occurred more often with invasive but less virulent serotypes

Launes C. Pediatr Infect Dis J. 2012;doi:10.1097/INF.0b013e31824f25b0.

Viral coinfections occurred significantly more often in invasive pneumococcal disease episodes caused by nonhighly invasive serotypes in children aged younger than 5 years, according to study results recently published online.

To determine the proportion of invasive pneumococcal disease cases in which a virus was detected, and examine the association between viral coinfections and pneumococcal serotypes, researchers conducted a study of admissions to a 345-bed tertiary care pediatric hospital from 2008 to 2009. Information was collected from admitted patients aged 5 years or younger with invasive pneumococcal disease, including clinical manifestations, outcomes and vaccination status, as well as symptoms of viral respiratory infection in the month before admission.

During the study period, invasive pneumococcal disease was identified in 71 patients, of whom 87% (62/71) received the primary clinical diagnosis of pneumonia often complicated by empyema (43/62; 69%).

Further analysis revealed that viral coinfection was common (44/71; 62%), with rhinovirus and influenza virus being the most frequently observed. Highly invasive serotypes were found in 31 of 71 patients, of whom 15 had viral coinfection. Viral coinfections occurred significantly more often in those episodes caused by nonhighly invasive serotypes (72%), which indicated that a viral synergism could aid those serotypes to make invasiveness more likely.

According to the researchers: “In patients without a respiratory [invasive pneumococcal disease] clinical diagnosis — bacteremia, meningitis, arthritis or sepsis — the rate of viral detections was also high, suggesting that viral coinfection is not only important because it causes a direct viral damage in lower respiratory tract but also because it is likely to favor specific local factors that would help pneumococcus invasion by an hematogenous way. This would also explain the relation of viral coinfection with meningitis or other [invasive pneumococcal disease] clinical diagnoses, as observed by others.”

Disclosure: The researchers report no relevant financial disclosures.

Follow the PediatricSuperSite.com on Twitter.