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"Streptococcus pneumoniae - isolation "
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Causes of severe pneumonia requiring hospital admission in children without HIV infection from Africa and Asia: the PERCH multi-country case-control study
by
Machuka, Eunice M.
,
Morpeth, Susan C.
,
Simões, Eric A.F.
in
Adenoviruses
,
Bacteria
,
Bangladesh - epidemiology
2019
Pneumonia is the leading cause of death among children younger than 5 years. In this study, we estimated causes of pneumonia in young African and Asian children, using novel analytical methods applied to clinical and microbiological findings.
We did a multi-site, international case-control study in nine study sites in seven countries: Bangladesh, The Gambia, Kenya, Mali, South Africa, Thailand, and Zambia. All sites enrolled in the study for 24 months. Cases were children aged 1–59 months admitted to hospital with severe pneumonia. Controls were age-group-matched children randomly selected from communities surrounding study sites. Nasopharyngeal and oropharyngeal (NP-OP), urine, blood, induced sputum, lung aspirate, pleural fluid, and gastric aspirates were tested with cultures, multiplex PCR, or both. Primary analyses were restricted to cases without HIV infection and with abnormal chest x-rays and to controls without HIV infection. We applied a Bayesian, partial latent class analysis to estimate probabilities of aetiological agents at the individual and population level, incorporating case and control data.
Between Aug 15, 2011, and Jan 30, 2014, we enrolled 4232 cases and 5119 community controls. The primary analysis group was comprised of 1769 (41·8% of 4232) cases without HIV infection and with positive chest x-rays and 5102 (99·7% of 5119) community controls without HIV infection. Wheezing was present in 555 (31·7%) of 1752 cases (range by site 10·6–97·3%). 30-day case-fatality ratio was 6·4% (114 of 1769 cases). Blood cultures were positive in 56 (3·2%) of 1749 cases, and Streptococcus pneumoniae was the most common bacteria isolated (19 [33·9%] of 56). Almost all cases (98·9%) and controls (98·0%) had at least one pathogen detected by PCR in the NP-OP specimen. The detection of respiratory syncytial virus (RSV), parainfluenza virus, human metapneumovirus, influenza virus, S pneumoniae, Haemophilus influenzae type b (Hib), H influenzae non-type b, and Pneumocystis jirovecii in NP-OP specimens was associated with case status. The aetiology analysis estimated that viruses accounted for 61·4% (95% credible interval [CrI] 57·3–65·6) of causes, whereas bacteria accounted for 27·3% (23·3–31·6) and Mycobacterium tuberculosis for 5·9% (3·9–8·3). Viruses were less common (54·5%, 95% CrI 47·4–61·5 vs 68·0%, 62·7–72·7) and bacteria more common (33·7%, 27·2–40·8 vs 22·8%, 18·3–27·6) in very severe pneumonia cases than in severe cases. RSV had the greatest aetiological fraction (31·1%, 95% CrI 28·4–34·2) of all pathogens. Human rhinovirus, human metapneumovirus A or B, human parainfluenza virus, S pneumoniae, M tuberculosis, and H influenzae each accounted for 5% or more of the aetiological distribution. We observed differences in aetiological fraction by age for Bordetella pertussis, parainfluenza types 1 and 3, parechovirus–enterovirus, P jirovecii, RSV, rhinovirus, Staphylococcus aureus, and S pneumoniae, and differences by severity for RSV, S aureus, S pneumoniae, and parainfluenza type 3. The leading ten pathogens of each site accounted for 79% or more of the site's aetiological fraction.
In our study, a small set of pathogens accounted for most cases of pneumonia requiring hospital admission. Preventing and treating a subset of pathogens could substantially affect childhood pneumonia outcomes.
Bill & Melinda Gates Foundation.
Journal Article
Long-Term Azithromycin Reduces Haemophilus influenzae and Increases Antibiotic Resistance in Severe Asthma
by
Choo, Jocelyn M.
,
Reynolds, Paul N.
,
Simpson, Jodie L.
in
Adult
,
Aged
,
Anti-Bacterial Agents - administration & dosage
2019
The macrolide antibiotic azithromycin reduces exacerbations in adults with persistent symptomatic asthma. However, owing to the pleotropic properties of macrolides, unintended bacteriological consequences such as augmented pathogen colonization or dissemination of antibiotic-resistant organisms can occur, calling into question the long-term safety of azithromycin maintenance therapy.
To assess the effects of azithromycin on the airway microbiota, pathogen abundance, and carriage of antibiotic resistance genes.
16S rRNA sequencing and quantitative PCR were performed to assess the effect of azithromycin on sputum microbiology from participants of the AMAZES (Asthma and Macrolides: The Azithromycin Efficacy and Safety) trial: a 48-week, double-blind, placebo-controlled trial of thrice-weekly 500 mg oral azithromycin in adults with persistent uncontrolled asthma. Pooled-template shotgun metagenomic sequencing, quantitative PCR, and isolate whole-genome sequencing were performed to assess antibiotic resistance.
Paired sputum samples were available from 61 patients (
= 34 placebo,
= 27 azithromycin). Azithromycin did not affect bacterial load (
= 0.37) but did significantly decrease Faith's phylogenetic diversity (
= 0.026) and
load (
< 0.0001). Azithromycin did not significantly affect levels of
,
,
, or
. Of the 89 antibiotic resistance genes detected, five macrolide resistance genes and two tetracycline resistance genes were increased significantly.
In patients with persistent uncontrolled asthma, azithromycin reduced airway
load compared with placebo but did not change total bacterial load. Macrolide resistance increased, reflecting previous studies. These results highlight the need for studies assessing the efficacy of nonantibiotic macrolides as a long-term therapy for patients with persistent uncontrolled asthma.
Journal Article
Comparative Immunogenicity and Efficacy of 13-Valent and 7-Valent Pneumococcal Conjugate Vaccines in Reducing Nasopharyngeal Colonization: A Randomized Double-Blind Trial
by
Dagan, Ron
,
Juergens, Christine
,
Greenberg, David
in
Antibodies, Bacterial - blood
,
ARTICLES AND COMMENTARIES
,
Bacterial diseases
2013
Background. The 13-valent pneumococcal conjugate vaccine (PCV13) was licensed to replace the 7-valent pneumococcal conjugate vaccine (PCV7) based on serological noninferiority criteria. To date no randomized PCV13 pediatric trial has included clinical endpoints. Methods. This randomized double-blind trial compared the impact of PCV13 versus PCV7 on nasopharyngeal (NP) colonization and immunogenicity. Healthy infants were randomized (1:1) to receive PCV7 or PCV13 at ages 2, 4, 6, and 12 months; NP swabs were collected at 2, 4, 6, 7, 12, 13, 18, and 24 months, and blood was drawn at 7 and 13 months. Rates of NP acquisition and prevalence, and serotype-specific immunoglobulin G (IgG) concentrations were assessed. Results. The per protocol analysis population included 881 PCV13 and 873 PCV7 recipients. PCV13 significantly reduced NP acquisition of the additional PCV13 serotypes 1, 6A, 7F, and 19A; the cross-reacting serotype 6C; and the common PCV7 serotype 19F. For serotype 3, and the other PCV7 serotypes, there were no significant differences between the vaccine groups. There were too few serotype 5 events to draw inference. The impact on prevalence at predefined time points was similar to that observed with NP acquisition. PCV13 elicited significantly higher IgG responses for PCV13 additional serotypes and serotype 19F, and similar or lower responses for 6/7 PCV7 serotypes. Conclusions. PCV13 resulted in lower acquisition and prevalence of NP colonization than PCV7 did for 4 additional PCV13 serotypes, and serotypes 6C and 19F. It was comparable with PCV7 for all other common serotypes. These findings predict vaccine effectiveness through both direct and indirect protection. Clinical Trials Registration. NCT00508742.
Journal Article
Long-term effects of azithromycin mass administration to reduce childhood mortality on Streptococcus pneumoniae antimicrobial resistance: a population-based, cross-sectional, follow-up carriage survey
by
Cave, Rory
,
Samikwa, Lyson
,
Kwambana-Adams, Brenda
in
Anti-Bacterial Agents - administration & dosage
,
Anti-Bacterial Agents - therapeutic use
,
Antibiotics
2025
Mass drug administration (MDA) programmes with the macrolide antibiotic azithromycin to reduce childhood mortality are expanding in Africa; however, concerns remain about the long-term effects of these programmes on antimicrobial resistance (AMR). We aimed to evaluate the persistence and spread of Streptococcus pneumoniae AMR following a community-randomised MDA trial.
This population-based, cross-sectional, pneumococcal carriage survey was conducted in Mangochi, Malawi, 3·5 years after the MORDOR trial, in which communities received twice-yearly azithromycin or placebo for 2 years. Eligible participants in this carriage survey were children aged 4–9 years who lived in an azithromycin-treated or placebo-treated cluster during the MORDOR trial, and children aged 1–3 years who were resident in a cluster but born after the MORDOR trial ended. Nasopharyngeal swabs were collected from participants and analysed by whole genome sequencing; pneumococcal genomes obtained from a distant site in Malawi, in which MDA had not been conducted, were used as reference genomes. The primary outcome was the prevalence of S pneumoniae macrolide resistance, comparing placebo-treated and azithromycin-treated clusters at baseline, 6 months post-MDA, and 3·5 years post-MDA.
Between April 8 and May 14, 2021, 924 children aged 1–9 years were screened, of whom 19 were excluded and 905 were recruited to the follow-up carriage survey: 452 from azithromycin-treated clusters and 453 from placebo-treated clusters of the MORDOR trial. We assessed 426 isolates from these participants (190 from azithromycin-treated clusters and 236 from placebo-treated clusters), as well as samples from the baseline of the MORDOR trial (164 isolates; 83 from azithromycin-treated clusters and 81 from placebo-treated clusters) and from 6 months post-MDA (223 isolates; 119 from azithromycin-treated clusters and 104 from placebo-treated clusters). In azithromycin-treated clusters, macrolide resistance increased from 21·7% (95% CI 14·2–31·7; 18 of 83 isolates) at baseline to 31·9% (24·2–40·8; 38 of 119 isolates) 6 months post-MDA and to 32·1% (25·9–39·0; 61 of 190 isolates) 3·5 years post-MDA. In placebo-treated clusters, resistance increased from 21·0% (13·5–31·1; 17 of 81 isolates) at baseline to 25·0% (17·7–34·1; 26 of 104 isolates) 6 months post-MDA and to 30·9% (25·4–37·1; 73 of 236 isolates) 3·5 years post-MDA. No significant differences were observed in odds ratios between treatment groups across the survey timepoints: 0·97 (95% CI 0·36–2·55) at baseline, 1·46 (0·67–3·17) at 6 months post-MDA, and 1·12 (0·66–1·91) at 3·5 years post-MDA. Macrolide resistance in the non-MDA site remained stable: 16·9% (95% CI 12·8–21·8; 45 of 267 isolates) at baseline, 16·5% (13·3–20·3; 70 of 424 isolates) at 6 months, and 16·5% (12·5–21·4; 44 of 267 isolates) at 2·5 years. Among children born into azithromycin-treated clusters after MDA, macrolide resistance was 36·0% (27·7–45·1; 41 of 114 children). Multidrug resistance to at least three antibiotic classes was significantly higher in azithromycin-treated (p=0·0015) and placebo-treated (p<0·0001) clusters than in the comparator population at 3·5 years post-MDA and was associated with integrative conjugative elements.
Azithromycin MDA is associated with macrolide resistance that persists and potentially spreads to untreated populations. The co-existence of multidrug resistance and transmissible resistance on integrative conjugative elements in these populations is a public health concern. Careful monitoring of AMR is essential in areas where MDA is implemented.
The Gates Foundation, the National Institute for Health and Care Research, and the Wellcome Trust.
Journal Article
Effect of a Reduced PCV10 Dose Schedule on Pneumococcal Carriage in Vietnam
by
Toizumi, Michiko
,
Do, Hung Thai
,
Kitamura, Noriko
in
Bacterial Infections
,
Carrier State - epidemiology
,
Carrier State - microbiology
2024
After pneumococcal disease and colonization have been controlled through vaccination campaigns, a reduced pneumococcal conjugate vaccine (PCV) schedule may be sufficient to sustain that control at reduced costs.
We investigated whether a single primary dose and booster dose (1p+1) of the 10-valent PCV (PCV10) would be noninferior to alternative dose schedules in sustaining control of carriage of pneumococcal serotypes included in the vaccine. In Nha Trang, Vietnam, an area in which PCV had not been used previously, a PCV10 catch-up campaign was conducted in which the vaccine was offered to children younger than 3 years of age, after which a cluster-randomized trial was conducted in which children received PCV10 at 2, 3, and 4 months of age (3p+0 group); at 2, 4, and 12 months of age (2p+1 group); at 2 and 12 months of age (1p+1 group); or at 12 months of age (0p+1 group). Annual carriage surveys in infants (4 to 11 months of age) and toddlers (14 to 24 months of age) were conducted from 2016 through 2020. The primary end point was protection against carriage of vaccine serotypes, evaluated in a noninferiority analysis in the 1p+1 group as compared with the 2p+1 and 3p+0 groups, 3.5 years after vaccine introduction (noninferiority margin, 5 percentage points). Noninferiority of the 0p+1 schedule was also evaluated.
In 2016, before the introduction of PCV10, vaccine-serotype carriage was found in 160 of 1363 infants (11.7%); in 2020, vaccine-serotype carriage was found in 6 of 333 (1.8%), 5 of 340 (1.5%), and 4 of 313 (1.3%) infants in the 1p+1, 2p+1, and 3p+0 groups, respectively, indicating noninferiority of 1p+1 to 2p+1 (difference, 0.3 percentage points; 95% confidence interval [CI], -1.6 to 2.2) and to 3p+0 (difference, 0.5 percentage points; 95% CI, -1.4 to 2.4). Similarly, 1p+1 was noninferior to 2p+1 and 3p+0 for protection against vaccine-serotype carriage among toddlers. In 2016, carriage of serotype 6A was found in 99 of 1363 infants (7.3%); in 2020, it was found in 12 of 333 (3.6%), 10 of 340 (2.9%), and 3 of 313 (1.0%) infants in the 1p+1, 2p+1, and 3p+0 groups, respectively. The 0p+1 schedule was also noninferior to the other three dose schedules among infants and toddlers, although cross-protection against serotype 6A was less common than with the other vaccination schedules. No PCV10-associated severe adverse effects were observed.
A reduced vaccination schedule involving a single primary dose and booster dose of PCV10 was noninferior to alternative schedules in protecting against vaccine-serotype carriage in infants and toddlers. (Funded by the Bill and Melinda Gates Foundation and others; ClinicalTrials.gov number, NCT02961231.).
Journal Article
The impact of pneumococcal vaccination and nasopharyngeal colonization on the performance of a serotype-specific urine antigen detection (SSUAD) assay
2025
To better inform pneumococcal immunization policies, ongoing surveillance for pneumococcal community-acquired pneumonia (CAP) is crucial. To estimate the serotype-specific CAP burden of pneumococcal disease following the introduction of a new 15-valent pneumococcal conjugate vaccine (PCV), V114, a 15-plex serotype-specific urine antigen detection (SSUAD) assay was developed as a tool for surveillance of Streptococcuspneumoniae serotypes. V114–017 (NCT03547167; EudraCT 2017–004915-38) was a phase 3 randomized controlled trial in which participants (18–49 years) received V114 or 13-valent PCV (PCV13; as an active comparator), followed 6 months later by 23-valent pneumococcal polysaccharide vaccine (PPSV23). Here, we report findings from a prespecified sub-study nested within the phase 3 trial that descriptively assessed the impact of nasopharyngeal/oropharyngeal (NP/OP) carriage and pneumococcal vaccination on serotype detection with the SSUAD assay. In total, 301 individuals (all American Indian/Alaska Native) participated in the sub-study. NP/OP and urine samples were collected at 10 timepoints between baseline (prior to vaccination) and Month 7 (30 days following vaccination with PPSV23). NP/OP carriage was determined using qualitative polymerase chain reaction for pneumococcus detection and serotyping, and urine samples were tested in parallel with SSUAD. At any timepoint, NP/OP carriage was <2.0 % for 10 of the V114 serotypes; carriage was ∼2.6 % for serotype 1 and ranged between 4.0 % and 7.0 % for serotypes 4, 5, 9V, and 33F. At baseline, serotype-specific pneumococcal polysaccharide antigens were detected by SSUAD in only six study participants for serotypes 19A, 19F, and 1. SSUAD positivity for serotypes 4, 5, and 9V increased transiently following vaccination with V114/PCV13 and PPSV23, while SSUAD positivity lasted the longest for serotype 19A following PPSV23 vaccination. In general, SSUAD positivity appeared unrelated to NP/OP carriage. Our findings suggest SSUAD can support pneumococcal disease surveillance and vaccine effectiveness research, excluding individuals with recent pneumococcal vaccination to avoid false-positives.
Journal Article
Effect of mass campaigns with full and fractional doses of pneumococcal conjugate vaccine (Pneumosil) on the reduction of nasopharyngeal pneumococcal carriage in Niger: a three-arm, open-label, cluster-randomised trial
by
Scott, J Anthony G
,
Brah, Souleymane
,
Karani, Angela
in
Carrier State - epidemiology
,
Carrier State - microbiology
,
Carrier State - prevention & control
2025
In settings with low pneumococcal conjugate vaccine (PCV) coverage, multi-age cohort mass campaigns could increase population immunity, and fractional dosing could increase affordability. We aimed to evaluate the effect of mass campaigns on nasopharyngeal pneumococcal carriage of Pneumosil (PCV10) in children aged 1–9 years in Niger.
In this three-arm, open-label, cluster-randomised trial, 63 clusters of one to four villages in Niger were randomly assigned (3:3:1) using block randomisation to receive campaigns consisting of a single full dose of a 10-valent PCV (Pneumosil), a single one-fifth dose of Pneumosil, or no campaign. Independently sampled carriage surveys were done among 2268 households 6 months before and after vaccination, collecting nasopharyngeal swabs from healthy children for culture and serotyping; those with contraindication to nasopharyngeal swabbing were excluded. The primary outcome was nasopharyngeal carriage of vaccine-serotype pneumococcus. We tested whether vaccine-type carriage was reduced in full-dose versus control clusters; and whether fractional doses were non-inferior to full-doses (lower bound 95% CI more than –7·5%), using generalised estimating equations to analyse cluster summaries at baseline and follow-up, controlling for covariates to estimate risk differences and their 95% CIs. The study is registered with ClinicalTrials.gov (NCT05175014) and the Pan-African Clinical Trials Registry (PACTR20211257448484).
Surveys were done between Dec 22, 2021, and March 18, 2022, and between Dec 12, 2022, and March 9, 2023. The vaccination campaign ran from June 15 to Aug 2, 2022. Participants' characteristics were consistent across surveys and groups. Pre-vaccination, vaccine-type carriage was 15·6% (149 of 955 participants) in the full-dose group, 17·9% (170 of 948) in the fractional-dose group, and 18·8% (60 of 320) in the control group. Post-vaccination, vaccine-type carriage was 4·6% (44 of 967) in the full-dose group, 8·0% (77 of 962) in the fractional-dose group, and 16·5% (53 of 321) in the control group. The primary analysis showed a risk difference of –16·2% (95% CI –28·6 to –3·0) between the full-dose group and control group (p=0·002 for superiority), and –3·8% (–6·1 to –1·6) between the full-dose group and fractional-dose group, meeting the non-inferiority criteria. No adverse events were judged to be related to vaccination.
Multi-age cohort campaigns had a marked effect on vaccine-type carriage and fractional-dose campaigns met non-inferiority criteria. Such campaigns should be considered in low-coverage settings, including humanitarian emergencies, to accelerate population protection.
EDCTP2 programme supported by the EU.
For the French translation of the abstract see Supplementary Materials section.
Journal Article
Shortened Antimicrobial Treatment for Acute Otitis Media in Young Children
by
Copelli, Susan J
,
Hoberman, Alejandro
,
Pope, Marcia A
in
Acute Disease
,
Allergies
,
Amoxicillin
2016
In children 6 to 23 months of age with otitis media, 5 days of antibiotic therapy was associated with less-favorable outcomes than standard 10-day treatment. The shorter course did not result in a lower rate of adverse events or of emergence of antimicrobial resistance.
Next to the common cold, acute otitis media is the most frequently diagnosed illness in children in the United States
1
and the most commonly cited indication for antimicrobial treatment.
2
Concerns about the possible encouragement of antimicrobial resistance have led to recommendations by some clinicians that antimicrobial agents be withheld in large subgroups of children with acute otitis media, unless symptoms persist or worsen.
3
However, two trials lend support for routine antimicrobial treatment in young children, because affected participants younger than 3 years of age who received antimicrobial treatment for 7 or 10 days had more favorable outcomes than those who . . .
Journal Article
Fractional Doses of Pneumococcal Conjugate Vaccine — A Noninferiority Trial
by
Bottomley, Christian
,
Gardiner, Elizabeth
,
Suaad, Badaud
in
Antibodies, Bacterial - blood
,
Antibodies, Bacterial - immunology
,
Antigens
2024
Pneumococcal conjugate vaccines are an important but costly part of childhood vaccination. This trial assessed immunogenicity of fractional-dose regimens — a key consideration as countries transition out of Gavi support.
Journal Article
Efficacy of a novel, protein-based pneumococcal vaccine against nasopharyngeal carriage of Streptococcus pneumoniae in infants: A phase 2, randomized, controlled, observer-blind study
by
Kampmann, Beate
,
Ota, Martin O.C.
,
Worwui, Archibald
in
Allergy and Immunology
,
Aluminum
,
Antigens
2017
•Pneumococcal protein antigens could provide serotype-independent protection.•Two PHiD-CV/dPly/PhtD vaccine formulations were assessed in healthy infants.•Both protein-based vaccines elicited immune responses to pneumococcal proteins.•The vaccines had no impact on pneumococcal nasopharyngeal carriage prevalence.•Future evaluations will assess their impact against pneumococcal disease endpoints.
Conserved pneumococcal proteins are potential candidates for inclusion in vaccines against pneumococcal diseases. In the first part of a two-part study, an investigational vaccine (PHiD-CV/dPly/PhtD-30) containing 10 pneumococcal serotype-specific polysaccharide conjugates (10VT) combined with pneumolysin toxoid and pneumococcal histidine triad protein D (30μg each) was well tolerated by Gambian children. Part two, presented here, assessed the efficacy of two PHiD-CV/dPly/PhtD formulations against pneumococcal nasopharyngeal carriage (NPC) prevalence in infants.
In this phase 2, randomized, controlled, observer-blind trial, healthy infants aged 8–10weeks, recruited from a peri-urban health center, were randomized (1:1:1:1:1:1) into six groups. Four groups received PHiD-CV/dPly/PhtD (10 or 30μg of each protein), PHiD-CV, or 13-valent pneumococcal conjugate vaccine at ages 2–3–4months (3+0 infant schedule) and two groups PHiD-CV/dPly/PhtD-30 or PHiD-CV at 2–4–9months (2+1 infant schedule). The primary objective was impact on non-10VT NPC at ages 5–9–12months. Secondary objectives included confirmatory analysis of protein dose superiority and safety/reactogenicity. Impact on pneumococcal NPC acquisition, bacterial load, and ply and phtD gene sequencing were explored.
1200 infants were enrolled between June 2011 and May 2012. Prevalences of pneumococcal (60–67%) and non-10VT (55–61%) NPC were high at baseline. Across all post-vaccination time points, efficacy of PHiD-CV/dPly/PhtD-10 and PHiD-CV/dPly/PhtD-30 against non-10VT NPC (3+0 schedule) was 1.1% (95% CI −21.5, 19.5) and 2.1% (−20.3, 20.3), respectively; efficacy of PHiD-CV/dPly/PhtD-30 (2+1 schedule) was 0.5% (−22.1, 18.9) versus PHiD-CV. No differences were observed in pneumococcal NPC acquisition, clearance, or bacterial load. Both protein-based vaccines elicited immune responses to pneumococcal proteins.
In this high carriage prevalence setting, inclusion of pneumococcal proteins in the PHiD-CV/dPly/PhtD investigational vaccine had no impact on pneumococcal NPC in infants, regardless of protein dose or schedule. Future evaluations will assess its impact against pneumococcal disease endpoints.
Funding: PATH, GlaxoSmithKline Biologicals SA. ClinicalTrials.gov identifier NCT01262872.
Journal Article