tetano
Editor, Senior Moderator
Clin Infect Dis
. 2020 Oct 30;ciaa1551.
doi: 10.1093/cid/ciaa1551. Online ahead of print.
Influenza-like Illness Exacerbates Pneumococcal Carriage in Older Adults
Willem R Miellet[SUP] 1 2 [/SUP], Janieke van Veldhuizen[SUP] 1 [/SUP], Mioara A Nicolaie[SUP] 1 3 [/SUP], Rob Mariman[SUP] 1 [/SUP], Hester J Bootsma[SUP] 1 [/SUP], Thijs Bosch[SUP] 1 [/SUP], Nynke Y Rots[SUP] 1 [/SUP], Elisabeth A M Sanders[SUP] 1 2 [/SUP], Josine van Beek[SUP] 1 [/SUP], Krzysztof Trzciński[SUP] 2 [/SUP]
Affiliations
Abstract
Background: In older adults pneumococcal disease is strongly associated with respiratory viral infections, but the impact of viruses on Streptococcus pneumoniae carriage prevalence and load remains poorly understood. Here, we investigated the effects of influenza-like illness (ILI) on pneumococcal carriage in community-dwelling older adults.
Methods: We investigated the presence of pneumococcal DNA in saliva samples collected in the 2014/2015 influenza season from 232 individuals aged ≥60 years at ILI-onset, followed by sampling 2-3 weeks and 7-9 weeks after the first sample. We also sampled 194 age-matched controls twice 2-3 weeks apart. Pneumococcal DNA was detected with quantitative-PCRs targeting piaB and lytA genes in raw and in culture-enriched saliva. Bacterial and pneumococcal abundances were determined in raw saliva with 16S and piaB quantification.
Results: The prevalence of pneumococcus-positive samples was highest at onset of ILI (18% or 42/232) and lowest among controls (13% or 26/194, and 11% or 22/194, at the first and second sampling moment, respectively), though these differences were not significant. Pneumococcal carriage was associated with exposure to young children (OR:2.71, 95%CI 1.51-5.02, p<0.001), and among asymptomatic controls with presence of rhinovirus infection (OR:4.23; 95%CI 1.16-14.22, p<0.05). When compared with carriers among controls, pneumococcal absolute abundances were significantly higher at onset of ILI (p<0.01), and remained elevated beyond recovery from ILI (p<0.05). Finally, pneumococcal abundances were highest in carriage events newly-detected after ILI-onset (estimated geometric mean 1.21E -5, 95%CI 2.48E -7-2.41E -5, compared with pre-existing carriage).
Conclusions: ILI exacerbates pneumococcal colonization of the airways in older adults, and this effect persists beyond recovery from ILI.
Keywords: Streptococcus pneumoniae; carriage; influenza-like illness; older adults.
. 2020 Oct 30;ciaa1551.
doi: 10.1093/cid/ciaa1551. Online ahead of print.
Influenza-like Illness Exacerbates Pneumococcal Carriage in Older Adults
Willem R Miellet[SUP] 1 2 [/SUP], Janieke van Veldhuizen[SUP] 1 [/SUP], Mioara A Nicolaie[SUP] 1 3 [/SUP], Rob Mariman[SUP] 1 [/SUP], Hester J Bootsma[SUP] 1 [/SUP], Thijs Bosch[SUP] 1 [/SUP], Nynke Y Rots[SUP] 1 [/SUP], Elisabeth A M Sanders[SUP] 1 2 [/SUP], Josine van Beek[SUP] 1 [/SUP], Krzysztof Trzciński[SUP] 2 [/SUP]
Affiliations
- PMID: 33124669
- DOI: 10.1093/cid/ciaa1551
Abstract
Background: In older adults pneumococcal disease is strongly associated with respiratory viral infections, but the impact of viruses on Streptococcus pneumoniae carriage prevalence and load remains poorly understood. Here, we investigated the effects of influenza-like illness (ILI) on pneumococcal carriage in community-dwelling older adults.
Methods: We investigated the presence of pneumococcal DNA in saliva samples collected in the 2014/2015 influenza season from 232 individuals aged ≥60 years at ILI-onset, followed by sampling 2-3 weeks and 7-9 weeks after the first sample. We also sampled 194 age-matched controls twice 2-3 weeks apart. Pneumococcal DNA was detected with quantitative-PCRs targeting piaB and lytA genes in raw and in culture-enriched saliva. Bacterial and pneumococcal abundances were determined in raw saliva with 16S and piaB quantification.
Results: The prevalence of pneumococcus-positive samples was highest at onset of ILI (18% or 42/232) and lowest among controls (13% or 26/194, and 11% or 22/194, at the first and second sampling moment, respectively), though these differences were not significant. Pneumococcal carriage was associated with exposure to young children (OR:2.71, 95%CI 1.51-5.02, p<0.001), and among asymptomatic controls with presence of rhinovirus infection (OR:4.23; 95%CI 1.16-14.22, p<0.05). When compared with carriers among controls, pneumococcal absolute abundances were significantly higher at onset of ILI (p<0.01), and remained elevated beyond recovery from ILI (p<0.05). Finally, pneumococcal abundances were highest in carriage events newly-detected after ILI-onset (estimated geometric mean 1.21E -5, 95%CI 2.48E -7-2.41E -5, compared with pre-existing carriage).
Conclusions: ILI exacerbates pneumococcal colonization of the airways in older adults, and this effect persists beyond recovery from ILI.
Keywords: Streptococcus pneumoniae; carriage; influenza-like illness; older adults.