Josine Van Beek, Netherlands
National Institute for Public Health and the Environment Centre for Infectious Disease Control NetherlandsAuthor Of 1 Presentation
DYNAMICS OF PNEUMOCOCCAL CARRIAGE ASSOCIATED WITH INFLUENZA-LIKE ILLNESS IN COMMUNITY-DWELLING OLDER ADULTS (ID 975)
Abstract
Background
In older adults, pneumococcal disease is strongly associated with viral respiratory infections, though the impact of viruses on pneumococcal carriage remains poorly understood. Here, we have investigated effects of influenza-like illness (ILI) on pneumococcal carriage in older adults.
Methods
Pneumococcal presence was determined in saliva samples that were collected in the 2014/2015 influenza season from individuals aged ≥60 years, including 232 individuals with ILI sampled trice and 194 controls sampled twice. Pneumococcal carriage was detected with quantitative-PCRs targeting piaB and lytA genes in minimally-processed saliva and culture-enriched saliva. Bacterial and pneumococcal abundances were determined in minimally-processed saliva. Respiratory viruses were detected in nasopharyngeal and oropharyngeal samples using qPCR.
Results
In general, pneumococcal carriage was significantly associated with exposure to young children and rhinovirus infection. The prevalence of pneumococcal carriage was highest at ILI-onset (18%) and lowest among controls (11-13%). Compared with controls, both absolute and relative pneumococcal abundances were significantly elevated at ILI-onset and remained elevated 7-9 weeks later. Pneumococcal abundances were highest in individuals with carriage acquisition between ILI-onset and 2-3 weeks later.
Conclusions
Our findings support the notion that in older adults acute respiratory infections favor pneumococcal colonization of the upper respiratory tract and this impact persists beyond recovery from ILI.