Re-evaluation of Streptococcus pneumoniae carriage in Portuguese elderly by qPCR increases carriage estimates and unveils an expanded pool of serotypes.

Sci Rep

Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.

Published: May 2020

Streptococcus pneumoniae (pneumococcus) is a leading cause of infections worldwide. Disease is preceded by asymptomatic colonization of the upper respiratory tract. Classical culture-based methods (CCBM) suggest that colonization in the elderly is <5%. Recently, use of qPCR has challenged these observations. We estimated pneumococcal carriage prevalence and serotypes among Portuguese elderly using qPCR and compared results with those obtained by CCBM. Nasopharyngeal and oropharyngeal paired samples (599 each) of individuals over 60 years living in nursing (n = 299) or family (n = 300) homes were screened for the presence of pneumococci by qPCR targeting lytA and piaB. Positive samples were molecular serotyped. Use of qPCR improved detection of pneumococci in oropharyngeal samples compared to CCBM: from 0.7% to 10.4% (p < 0.001) in the nursing home collection, and from 0.3% to 5.0% (p < 0.001) in the family home collection. No significant differences were observed between both methods in nasopharyngeal samples (5.4% vs. 5.4% in the nursing homes; and 4.3% vs. 4.7% in the family homes). Twenty-one serotypes/serogroups were detected by qPCR compared to 14 by CCBM. In conclusion, use of qPCR suggests that pneumococcal carriage in Portuguese elderly is approximately 10%, and unveiled a large pool of serotypes. These results are important to understand progression to disease and impact of pneumococcal vaccines in the elderly.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7239868PMC
http://dx.doi.org/10.1038/s41598-020-65399-xDOI Listing

Publication Analysis

Top Keywords

streptococcus pneumoniae
8
re-evaluation streptococcus
4
pneumoniae carriage
4
carriage portuguese
4
portuguese elderly
4
elderly qpcr
4
qpcr increases
4
increases carriage
4
carriage estimates
4
estimates unveils
4

Similar Publications

Early onset neonatal bloodstream infections in South African hospitals.

BMC Infect Dis

January 2025

Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, PO Box 241, Cape Town, 8000, South Africa.

Background: Neonatal sepsis is a leading cause of death in low- and middle- income countries (LMIC). Increasing antibiotic resistance in early onset (< 72 h of life) bloodstream infection (EO-BSI) pathogens in LMIC has reduced the effectiveness of the recommended empiric antibiotic regimen (ampicillin plus gentamicin).

Methods: We retrospectively analysed blood culture-confirmed EO-BSI episodes at nine neonatal units from three central and six peripheral hospitals in the Western Cape Province, South Africa between 1 January 2017 and 31 December 2018.

View Article and Find Full Text PDF

SPD_0410 negatively regulates capsule polysaccharide synthesis and virulence in D39.

Front Microbiol

January 2025

Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders and Chongqing Key Laboratory of Pediatric Metabolism and Inflammatory Diseases, Chongqing, China.

capsular polysaccharide (CPS) is a crucial virulence factor for this pathogenic bacterium and is partially under transcriptional control. In this study, we used electrophoretic mobility shift assays and DNA enzyme footprinting to identified the hypothetical protein SPD_0410 as a negative regulator of locus. Our results showed that the D39Δ mutant strain exhibited significantly elevated CPS levels compared to the parental strain D39s.

View Article and Find Full Text PDF

Background: Community-acquired pneumonia (CAP) was one of the most common causes of death in the European Union in 2017. Severity and mortality of CAP increase with age and an aging European population will require increased planning for prevention, control, and management of CAP. The purpose of this study was to provide an updated population-based estimate of the incidence of CAP requiring hospitalization in Northern Europe.

View Article and Find Full Text PDF

The development of safe and effective mucosal vaccines are hampered by safety concerns associated with adjuvants or live attenuated microbes. We previously demonstrated that targeting antigens to the human-Fc-gamma-receptor-I (hFcγRI) eliminates the need for adjuvants, thereby mitigating safety concerns associated with the mucosal delivery of adjuvant formulated vaccines. Here we evaluated the role of the route of immunization in the mucosal immunity elicited by the hFcγRI-targeted vaccine approach.

View Article and Find Full Text PDF

Enhanced pathogen identification among patients with clinically suspected meningitis.

S Afr J Infect Dis

December 2024

Division of Medical Microbiology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.

Background: Delayed or incorrect treatment of meningitis may result in adverse patient outcomes. However, laboratory testing in resource-limited settings is often limited to conventional diagnostic methods. We explored the utility of syndromic molecular assays for diagnosis.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!