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Background Streptococcus pneumoniae interacts with numerous viral respiratory pathogens in the upper airway. It is unclear whether similar interactions occur with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods We collected saliva specimens from working-age adults undergoing SARS-CoV-2 molecular testing at outpatient clinics and via mobile community-outreach testing between July and November 2020 in Monterey County, California. After bacterial culture enrichment, we tested for pneumococci by means of quantitative polymerase chain reaction targeting the lytA and piaB genes, and we measured associations with SARS-CoV-2 infection using conditional logistic regression. Results Analyses included 1278 participants, with 564 enrolled in clinics and 714 enrolled through outreach-based testing. The prevalence of pneumococcal carriage was 9.2% (117 of 1278) among all participants (11.2% [63 of 564] in clinic-based testing and 7.6% [54 of 714] in outreach-based testing). The prevalence of SARS-CoV-2 infection was 27.4% (32 of 117) among pneumococcal carriers and 9.6% (112 of 1161) among noncarriers (adjusted odds ratio [aOR], 2.73 [95% confidence interval (CI): 1.58–4.69). Associations between SARS-CoV-2 infection and pneumococcal carriage were enhanced in the clinic-based sample (aOR, 4.01 [95% CI: 2.08–7.75]) and among symptomatic participants (3.38 [1.35–8.40]), compared with findings within the outreach-based sample and among asymptomatic participants. The adjusted odds of SARS-CoV-2 coinfection increased 1.24-fold (95% CI: 1.00–1.55-fold) for each 1-unit decrease in piaB quantitative polymerase chain reaction cycle threshold value among pneumococcal carriers. Finally, pneumococcal carriage modified the association of SARS-CoV-2 infection with recent exposure to a suspected coronavirus disease 2019 case (aOR, 7.64 [95% CI: 1.91–30.7] and 3.29 [1.94–5.59]) among pneumococcal carriers and noncarriers, respectively). Conclusions Associations of pneumococcal carriage detection and density with SARS-CoV-2 suggest a synergistic relationship in the upper airway. Longitudinal studies are needed to determine interaction mechanisms between pneumococci and SARS-CoV-2.

Background Among older adults, 13-valent pneumococcal conjugate vaccine (PCV13) has been found efficacious against nonbacteremic pneumonia associated with vaccine-serotype pneumococci. However, the burden of lower respiratory tract infection (LRTI) and pneumonia preventable by direct immunization of older adults continues to be debated. Methods We analyzed data from an open cohort of adults aged ≥65 years enrolled in Kaiser Permanente Southern California health plans from 2016 to 2019 who received PCV13 concordant with US Advisory Committee on Immunization Practices guidelines. We estimated PCV13 vaccine effectiveness (VE) via the adjusted hazard ratio for first LRTI and pneumonia episodes during each respiratory season, comparing PCV13-exposed and PCV13-unexposed time at risk for each participant using a self-matched inference framework. Analyses used Cox proportional hazards models, stratified by individual. Results Among 42 700 adults who met inclusion criteria, VE was 9.5% (95% confidence interval [CI], 2.2% to 16.3%) against all-cause medically attended LRTI and 8.8% (95% CI, –.2% to 17.0%) against all-cause medically attended pneumonia. In contrast, we did not identify evidence of protection against LRTI and pneumonia following receipt of the 23-valent pneumococcal polysaccharide vaccine. PCV13 prevented 0.7 (95% CI, .2 to 1.4) and 0.5 (95% CI, .0 to 1.0) cases of LRTI and pneumonia, respectively, per 100 vaccinated persons annually; over 5 years, 1 case of LRTI and 1 case of pneumonia were prevented for every 27 and 42 individuals vaccinated, respectively. Conclusions PCV13 vaccination among older adults substantially reduced incidence of medically attended respiratory illness. Direct immunization of older adults is an effective strategy to combat residual disease burden associated with PCV13-type pneumococci.

Background Pneumococcal serotypes differ in antimicrobial susceptibility. However, patterns and causes of this variation are not comprehensively understood. Methods We undertook a systematic review of epidemiologic studies of pneumococci isolated from carriage or invasive disease among children globally from 2000–2019. We evaluated associations of each serotype with nonsusceptibility to penicillin, macrolides, and trimethoprim/sulfamethoxazole. We evaluated differences in the prevalence of nonsusceptibility to major antibiotic classes across serotypes using random-effects meta-regression models and assessed changes in prevalence of nonsusceptibility after implementation of pneumococcal conjugate vaccines (PCVs). We also evaluated associations between biological characteristics of serotypes and their likelihood of nonsusceptibility to each drug. Results We included data from 129 studies representing 32 187 isolates across 52 countries. Within serotypes, the proportion of nonsusceptible isolates varied geographically and over time, in settings using and those not using PCVs. Factors predicting enhanced fitness of serotypes in colonization as well as enhanced pathogenicity were each associated with higher likelihood of nonsusceptibility to penicillin, macrolides, and trimethoprim/sulfamethoxazole. Increases in prevalence of nonsusceptibility following PCV implementation were evident among non-PCV serotypes, including 6A, 6C, 15A, 15B/C, 19A, and 35B; however, this pattern was not universally evident among non-PCV serotypes. Postvaccination increases in nonsusceptibility for serotypes 6A and 19A were attenuated in settings that implemented PCV13. Conclusions In pneumococci, nonsusceptibility to penicillin, macrolides, and trimethoprim/sulfamethoxazole is associated with more frequent opportunities for antibiotic exposure during both prolonged carriage episodes and when serotypes cause disease. These findings suggest multiple pathways leading to resistance selection in pneumococci.

Background Reduced-dose pneumococcal conjugate vaccine (PCV) schedules are under consideration in countries where children are recommended to receive 3 doses. Whereas PCV-derived protection against vaccine-serotype colonization is responsible for herd effects of vaccination, dose-specific PCV effectiveness against colonization endpoints is not known. We aimed to assess the performance of differing PCV schedules against vaccine-serotype colonization in children. Methods From 2009–2016, we monitored pneumococcal carriage in southern Israel, where children should receive PCV at ages 2 months, 4 months, and 12 months (2 primary [p] +1 booster [b] schedule). We analyzed nasopharyngeal swabs and vaccination histories from 5928 children aged 0–59 months without symptoms of diseases potentially attributable to pneumococci. Matching individuals on age, sex, ethnicity, visit timing, and recent antibiotic receipt, we measured schedule-specific 7-valent PCV (PCV7) and 13-valent PCV (PCV13) effectiveness against vaccine-serotype colonization in a modified case-control framework. We sampled from the distribution of all possible case-control match assignments for statistical analyses. Results Receiving 2 primary-series PCV13 doses conferred 53% (95% confidence interval [CI], 32–67%) protection against PCV13-serotype colonization at ages ≤12 months; 1 primary-series dose was not protective. A 2p+1b PCV13 series conferred 40% (95% CI, 4–67%) and 62% (95% CI, 33–83%) protection against PCV13-serotype colonization at ages 13–24 months and 25–59 months, respectively. Estimates suggested greater PCV13-conferred protection against PCV7-targeted serotypes than the 6 PCV13-only serotypes. As compared to children receiving 2p+1b PCV13 dosing, those receiving 1p+1b and 2p+0b schedules experienced 2.05-fold (95% CI, 1.12–5.00) and 3.33-fold (95% CI, 2.28–4.93) greater odds, respectively, of vaccine-serotype pneumococcal colonization at ages 13–24 months. Conclusions Our results demonstrate real-world effectiveness of 2p+1b PCV dosing against vaccine-serotype colonization. Reduced-dose schedules may confer lower protection against vaccine-serotype carriage during and beyond the first year of life.

Background Group A Streptococcus (GAS) is a leading cause of acute respiratory conditions that frequently result in antibiotic prescribing. Vaccines against GAS are currently in development. Methods We estimated the incidence rates of healthcare visits and antibiotic prescribing for pharyngitis, sinusitis, and acute otitis media (AOM) in the United States using nationally representative surveys of outpatient care provision, supplemented by insurance claims data. We estimated the proportion of these episodes attributable to GAS and to GAS emm types included in a proposed 30-valent vaccine. We used these outputs to estimate the incidence rates of outpatient visits and antibiotic prescribing preventable by GAS vaccines with various efficacy profiles under infant and school-age dosing schedules. Results GAS pharyngitis causes 19.1 (95% confidence interval [CI], 17.3–21.1) outpatient visits and 10.2 (95% CI, 9.0–11.5) antibiotic prescriptions per 1000 US persons aged 0–64 years, annually. GAS pharyngitis causes 93.2 (95% CI, 82.3–105.3) visits and 53.2 (95% CI, 45.2–62.5) antibiotic prescriptions per 1000 children ages 3–9 years, annually, representing 5.9% (95% CI, 5.1–7.0%) of all outpatient antibiotic prescribing in this age group. Collectively, GAS-attributable pharyngitis, sinusitis, and AOM cause 26.9 (95% CI, 23.9–30.8) outpatient visits and 16.1 (95% CI, 14.0–18.7) antibiotic prescriptions per 1000 population, annually. A 30-valent GAS vaccine meeting the World Health Organization’s 80% efficacy target could prevent 5.4% (95% CI, 4.6–6.4%) of outpatient antibiotic prescriptions among children aged 3–9 years. If vaccine prevention of GAS pharyngitis made the routine antibiotic treatment of pharyngitis unnecessary, up to 17.1% (95% CI, 15.0–19.6%) of outpatient antibiotic prescriptions among children aged 3–9 years could be prevented. Conclusions An efficacious GAS vaccine could prevent substantial incidences of pharyngitis infections and associated antibiotic prescribing in the United States.

BackgroundReductions in otitis media (OM) burden following rollout of pneumococcal conjugate vaccines (PCVs) have exceeded predictions of vaccine impact. In settings with active surveillance, reductions in OM caused by vaccine-targeted pneumococcal serotypes have co-occurred with reductions in OM caused by other pathogens carried in the upper-respiratory tract of children. To understand these changes, we investigated the progression of vaccine-targeted and non-vaccine pneumococcal serotypes from carriage to OM before and after vaccine rollout.MethodsNasopharyngeal carriage prevalence of pneumococcus was monitored in prospective studies of Bedouin and Jewish children