Prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae in China: a meta-analysis

Serotypes and Genotypes of Streptococcus pneumoniae in an Unvaccinated Population in Suzhou, China

Background

Streptococcus pneumoniae is a significant etiological agent of infection and commonly inhabits the human nasopharynx, alongside other potentially pathogenic bacteria. In this study, S. pneumoniae strains were obtained from a community population and subjected to investigation of their phenotypes, genotypes, and vaccine coverage.

Methods

S. pneumoniae was isolated from nasopharyngeal swab samples of a healthy population in the Guangfu Community. Capsular serotypes and genotypes were identified using Quellung reaction and multilocus sequence typing (MLST), respectively. The antimicrobial susceptibility was tested using minimum inhibitory concentrations.

Results

In total, 500 unvaccinated people were sampled. Ninety-four S. pneumoniae strains were identified. Common serotypes were 19F, 6A, and 9V. The strain coverages of PCV13 and PPV23 were 61.7% and 58.5%, respectively. About 27.6% isolates were non-susceptible to penicillin, and over 80% were resistant to erythromycin and doxycycline. Among 27 novel sequence types (STs) identified in all strains, the most common STs were ST236 (6/94, 6.4%) and ST12669 (6/94, 6.4%). Nearly half of the strains were grouped into four clone complexes (CC12665, CC271, CC6011, and CC180), of which CC271 showed the highest resistance to PEN.

Conclusion

In our study, various drug-resistant clone complexes of Streptococcus pneumoniae were found in the healthy population, the elderly, and children. Consequently, pneumococcal vaccines should be included in the national immunization schedule to prevent disease spread.

Nasopharyngeal carriage of Streptococcus pneumoniae among children aged 30 days to <60 months in Beijing and Shenzhen, China (2018-2021) during pneumococcal conjugate vaccine introduction and the coronavirus disease (COVID-19) pandemic

Objectives

To describe the carriage rate, serotype distribution, and antimicrobial susceptibility patterns of Streptococcus pneumoniae (S. pneumoniae) nasopharyngeal (NP) isolates among healthy children aged 30 days to <60 months in the cities of Beijing and Shenzhen during 2018-2021.

Methods

A NP swab sample was collected among four annual cohorts of healthy children at routine well-child visits. S. pneumoniae was identified by culture, optochin sensitivity and bile solubility, serotypes determined by latex agglutination and Quellung, and antimicrobial susceptibility testing performed using E-test strips.

Results

S. pneumoniae NP carriage was 13.1% (645/4,911), with the highest S. pneumoniae carriage prevalence (15.3%) observed in 25 to <60 months. The carriage prevalence was 15.1% in children 13-24 months, 13.2% in children 7-12 months, and 8.2% in children 30 days to 6 months (P < 0.01). Living with siblings [20.0% vs. 9.4%: OR: 2.42 (95% CI: 2.05-2.87)] or attending day-care [31.8% vs. 11.3%: OR: 3.67 (95% CI: 2.94-4.57)] increased the risk (P < 0.01). During the period (January 2020-April 2021) of strict non-pharmaceutical interventions to prevent and control the COVID-19 pandemic, the proportion of children with S. pneumoniae colonization declined from 16.0% (94/587) to 5.8% (108/1,848) in Beijing while increasing from 14.5% (64/443) to 18.6% (379/2,033) in Shenzhen. Among S. pneumoniae isolates, 36.7% (237/645) belonged to 13-valent pneumococcal conjugate vaccine (PCV13) serotypes, 64.3% (408/645) were non-PCV13 serotypes, including 20.8% (134/645) non-serotypeable S. pneumoniae (NST). A total of 158/644 isolates (24.5%) were MDR. For the PCV13 isolates, MDR was detected in 36.3% (86/237) of isolates; in comparison, 17.6% (72/407) of non-PCV13 serotypes, including NST, were MDR (P < 0.01). S. pneumoniae NP carriage was detected in 10.7% of children with previous pneumococcal vaccination (PCV7 or PCV13 only) compared with 14.9% in children without previous pneumococcal vaccination.

Conclusions

The highest S. pneumoniae carriage prevalence were found in the oldest age group (25 to <60 months) and in children living with siblings or attending day-care. Vaccination with PCV7 or PCV13 was associated with lower PCV13-serotype colonization. In Beijing, S. pneumoniae carriage significantly declined during the COVID-19 pandemic.

Prevalence, serotype distribution and antimicrobial susceptibility profile of Streptococcus pneumoniae in sea nomads children <5 years of age in Wakatobi, Southeast Sulawesi, Indonesia: A cross-sectional study

OBJECTIVES

Indonesia started the nationwide introduction of pneumococcal conjugate vaccine (PCV) in 2022. Pre-vaccine data of Streptococcus pneumoniae across the country would be critical to enable vaccine impact evaluation in the future. This study evaluates colonization prevalence, factors associated with colonization, serotype distribution, and antimicrobial susceptibility profile of S. pneumoniae.

METHODS

We enrolled children <5 years old from the settlements of Bajau Tribe in Wakatobi, Southeast Sulawesi, Indonesia, from October 2018 to February 2019. Nasopharyngeal (NP) swab specimens were analyzed by culture, and isolates were serotyped using sequential multiplex PCR. Antibiotic susceptibility was performed by disc-diffusion method. Multivariable logistic regression was performed for risk factors analysis.

RESULTS

We collected 499 NP swab specimens. 61.9% were colonized with S. pneumoniae and 48,9 % of the isolates were PCV13-vaccine type. The most common serotypes were 23F, 6B, 19F, and 6A with 13.2%, 9.8%, 8.9%, and 8.0%, respectively. Exposure to cigarette smoke in the household and runny nose were significant risk factors to colonization with aOR 1.6 (1.1 - 2.3) and 2.1 (1.4 - 3.3), respectively.

CONCLUSION

Findings in this study may contribute to the baseline pre-vaccine data in the country that would be critical for the vaccine impact evaluation.

Limited protection of pneumococcal vaccines against emergent Streptococcus pneumoniae serotype 14/ST876 strains

PURPOSE

Streptococcus pneumoniae (Spn) is a major cause of child death. We investigated the epidemiology of S. pneumoniae in a pediatric fever clinic and explored the genomics basis of the limited vaccine response of serotype 14 strains worldwide.

METHODS

Febrile disease and pneumonia were diagnosed following criteria from the WHO at the end of 2019 at a tertiary children's hospital. Spn was isolated by culture from nasopharyngeal (NP) swabs. The density was determined by lytA-base qPCR. Isolates were serotyped by Quellung and underwent antimicrobial susceptibility testing. Whole-genome sequencing was employed for molecular serotyping, MLST, antibiotic gene determination, SNP calling, recombination prediction, and phylogenetic analysis.

RESULTS

The presence of pneumococcus in the nasopharynx (87.5%, 7/8, p = 0.0227) and a high carriage (100%, 7/7, p = 0.0123) were significantly associated with pneumonia development. Living with siblings (73.7%, 14/19, p = 0.0125) and non-vaccination (56.0%, 28/50, p = 0.0377) contributed significantly to the Spn carriage. Serotype 14 was the most prevalent strain (16.67%, 5/30). The genome analysis of 1497 serotype 14 strains indicated S14/ST876 strains were only prevalent in China, presented limited vaccine responses with higher recombination activities within its cps locus, and unique variation patterns in the genes wzg and lrp.

CONCLUSION

With the lifting of the one-child policy, it will be crucial for families with multiple children to get PCV vaccinations in China. Due to the highly variant cps locus and distinctive variation patterns in capsule shedding and binding proteins genes, the prevalent S14/ST876 strains have shown poor response to current vaccines. It is necessary to continue monitoring the molecular epidemiology of this vaccine escape clone.

Streptococcus pneumoniae as a colonizing agent of the Nasopharynx - Oropharynx in adults: A systematic review and meta-analysis

BACKGROUND

Streptococcus pneumoniae (Spn) is a commensal pathogen that usually colonizes the upper respiratory tract of children. Likewise, Spn colonization has been considered a critical factor in the development of pneumococcal invasive disease. However, Spn prevalence in adults remains unclear. This study performs a systematic review and meta-analysis to explore the prevalence of Spn Nasopharynx - Oropharynx Colonization (NOC) in adults.

METHODS

A Systematic review of scientific databases was utilized to identify eligible studies that follow strict selection criteria. Subsequently, a meta-analysis was conducted to establish NOC prevalence in adults (≥18 years old). The heterogeneity and sensitivity analyses were assessed using the microorganism identification technique, sample type, and age subgroups.

RESULTS

Initial selection includes 69 studies, with 37 selected for the meta-analysis, involving 23,724 individuals. The overall prevalence (95 % CI) of Spn NOC among adults was 6 % (5-9). The subgroup analysis revealed that young adults (YA), 18-64 years old, had a prevalence of 10 %, whereas older adults (OA), ≥65 years old, had a prevalence of 2 %. The identification of Spn NOC may vary depending on the method of diagnosis used. High heterogeneity (I2 > 90 %) was observed but diminished to 70 % when the analysis was restricted to oropharyngeal swabs as an identification method. Furthermore, heterogeneity decreased to 58 % when exclusively employing traditional culture as the identification method.

CONCLUSIONS

This study found a low prevalence of Spn NOC in adults. Notably, the prevalence of Spn NOC was higher in younger adults than in older adults. It is essential to highlight a significant heterogeneity among studies, which indicates there is no standardized method of Spn NOC identification.

Exploring factors shaping antibiotic resistance patterns in Streptococcus pneumoniae during the 2020 COVID-19 pandemic

Non-pharmaceutical interventions implemented to block SARS-CoV-2 transmission in early 2020 led to global reductions in the incidence of invasive pneumococcal disease (IPD). By contrast, most European countries reported an increase in antibiotic resistance among invasive Streptococcus pneumoniae isolates from 2019 to 2020, while an increasing number of studies reported stable pneumococcal carriage prevalence over the same period. To disentangle the impacts of the COVID-19 pandemic on pneumococcal epidemiology in the community setting, we propose a mathematical model formalizing simultaneous transmission of SARS-CoV-2 and antibiotic-sensitive and -resistant strains of S. pneumoniae. To test hypotheses underlying these trends five mechanisms were built into the model and examined: (1) a population-wide reduction of antibiotic prescriptions in the community, (2) lockdown effect on pneumococcal transmission, (3) a reduced risk of developing an IPD due to the absence of common respiratory viruses, (4) community azithromycin use in COVID-19 infected individuals, (5) and a longer carriage duration of antibiotic-resistant pneumococcal strains. Among 31 possible pandemic scenarios involving mechanisms individually or in combination, model simulations surprisingly identified only two scenarios that reproduced the reported trends in the general population. They included factors (1), (3), and (4). These scenarios replicated a nearly 50% reduction in annual IPD, and an increase in antibiotic resistance from 20% to 22%, all while maintaining a relatively stable pneumococcal carriage. Exploring further, higher SARS-CoV-2 R0 values and synergistic within-host virus-bacteria interaction mechanisms could have additionally contributed to the observed antibiotic resistance increase. Our work demonstrates the utility of the mathematical modeling approach in unraveling the complex effects of the COVID-19 pandemic responses on AMR dynamics.

Necrotizing Pneumonia With Extensive Lobar Cavitation

Pneumonia occupies one of the leading positions in morbidity and mortality worldwide. It is frequently categorized depending on the site of acquisition. Here, we present a case of a young woman who was admitted to the Emergency Department (ED) with cough, dyspnea, fever, and progressive worsening associated with palpitations and hypotension. An initial x-ray was followed by a computed tomography (CT) scan of the chest, which revealed signs of extensive left lung pneumonia with pleural effusion. Despite initial improvement after antibiotic treatment, the patient's condition declined. A repeat chest CT showed evidence of extensive lobar cavitations, leading to suspicion of tuberculosis.

Prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae among healthy children under 5 years of age in Hainan Province, China

BACKGROUND

The thirteen-valent pneumococcal conjugate vaccine (PCV13) is not included in the national immunization program and is administered voluntarily with informed consent in China. In preparation for assessing the impact of pilot introduction in Hainan Province, we conducted a carriage study among children under 5 years of age from four locations in Hainan Province, China.

METHODS

From March to June 2022, nasopharyngeal (NP) swabs, collected from healthy children aged younger than 59 months who lived in the 4 different locations (Haikou, Wanning, Baisha and Qiongzhong) in Hainan Province, were tested for pneumococcus using conventional culture. Pneumococcal isolates were serotyped using the Quellung reaction. Risk factors associated with pneumococcal colonization were assessed using univariate analysis and multivariable logistic regression adjusting for age, daycare attendance and other factors.

RESULTS

Pneumococcus was isolated in 710 (30.4%) of the 2333 children enrolled. Of 737 pneumococci, 29 serotypes were identified; 60.9% were PCV13 serotypes; the most common vaccine serotypes were 6B (20.4%), 19F (13.0%), 6A (11.9%) and 23F (6.1%); and the most common nonvaccine serotypes were 23A (12.9%), 34 (6.1%) and nontypeable (NT) pneumococci (5.6%). Children vaccinated with PCV13 had lower carriage (17.7% vs 32.5%; P = 0.0001) and fewer PCV13 serotypes (41.9% vs 62.7%; P = 0.0017) compared to unimmunized children. After adjustment, NP carriage was higher among children attending daycare (aOR = 2.3, 95% CI: 1.7-3.2), living in rural areas (aOR = 1.4, 95% CI: 1.1-1.8), living with siblings (aOR = 1.3, 95% CI: 1.0-1.6) and whose mothers had completed senior high/technical secondary school (aOR = 1.5, 95% CI: 1.1-2.0). In contrast, completion of 3-4 doses of PCV13 were associated with a lower carriage rate (aOR = 0.6, 95% CI: 0.4-0.9).

CONCLUSIONS

We established the baseline of pneumococcal carriage, serotype distribution and PCV13 immunization rates among healthy children under 5 years of age in Hainan Province, prior to the introduction of PCV13 into the national immunization program. The high proportion of PCV13 serotypes suggests that PCV13 introduction will likely have a substantial impact on pneumococcal carriage in Hainan Province.

Serotype Distribution and Multi Locus Sequence Type (MLST) of Erythromycin-Resistant Streptococcus Pneumoniae Isolates in Tehran, Iran

Background

The number of erythromycin-resistant Streptococcus pneumoniae has significantly increased around the world. The present study aimed to determine the serotype distribution and molecular epidemiology of the erythromycin-resistant Streptococcus pneumoniae (ERSP) isolated from patients with invasive disease.

Methods

A total of 44 Streptococcus pneumoniae isolates were tested for susceptibility to several antimicrobial agents. Additionally, the polymerase chain reaction (PCR) was applied to evaluate ERSP isolates in terms of the presence of erythromycin resistance genes (e.g., ermB and mefA). The isolates were serotyped using the sequential multiplex-PCR method, and molecular epidemiology was assessed through the multilocus sequence typing (MLST) analysis.

Results

The results represented multidrug resistance (MDR) in approximately half of the pneumococcal isolates. Among 22 ERSP isolates, 20 (90.9%) and 12 (56%) ones contained ermB and mefA, respectively. Further, 14 (31.8%), 3 (22.7%), and 19A (18.1%) were the common serotypes among the isolates. No significant correlation was observed between serotypes and erythromycin resistance genes. Furthermore, the MLST results revealed 18 different sequence types (STs), the top ones of which were ST3130 (3 isolates) and ST166 (3 isolates). Population genetic analysis disclosed that CC63 (32%), CC156 (18%), and CC320 (18%) were identified as the predominant clonal complexes.

Conclusions

The ERSP isolates exhibited high genetic diversity. The large frequency of MDR isolates suggests the emergence of high resistant strains, as well as the need to implement vaccination in the immunization schedule of Iran. These accumulating evidences indicate that 13-valent pneumococcal conjugate vaccines provided higher serotype coverage in the ERSP isolates.

Comparison of 14 respiratory pathogens among hospitalized children during and after the COVID-19 outbreak in Chaoshan area

BACKGROUND

Since January 2020, measures has been adopted in the Chaoshan area to limit the spread of COVID-19. Restrictions were removed after August 2020. At the same time, children returned to school. We previously reported the changes of 14 main respiratory pathogens in hospitalized children before and during the COVID-19 outbreak in Chaoshan area. However, the changes of respiratory pathogen spectrum in hospitalized children after the epidemic are still unknown, which will be elucidated in this study.

METHODS

There are 6201 children hospitalized with respiratory tract infection were enrolled in the study, which were divided into two groups: 2533 from outbreak group (1 January 2020-31 December 2020), and 3668 from post-outbreak group (1 January 2021-31 December 2021). Pharyngeal swab samples were collected. 14 respiratory tract pathogens were detected by liquid chip technology.

RESULTS

The positive rate of pathogen detection is significantly lower in the outbreak group (65.42%, 1657/2533) than that in the post-outbreak group (70.39%, 2582/3668; χ² = 17.15, P < 0.05). The Influenza A virus (FluA) detection rate was 1.9% (49) in 2020, but 0% (0) in 2021. The detection rates of Bordetella pertussis (BP) decreased from 1.4% (35) in 2020 to 0.5% (17) in 2021. In contrast, the detection rates of  Influenza B virus (FluB), Cytomegalovirus (CMV), Haemophilus influenzae (HI), Streptococcus pneumoniae (SP) increased from 0.3% (8), 24.7% (626), 2.0% (50) and 19.4% (491) in 2020 to 3.3% (121), 27.9% (1025), 4.6% (169), 22.8% (836) in 2021, respectively (P < 0.01).

CONCLUSIONS

The detection rates of pathogens such as FluA, FluB, CMV, HI, SP, BP were statistically different between 2020 and 2021. From 2020 to 2021, the positive rates of Flu, CMV, HI and SP increased, while the positive rates of FluA and BP decreased. After the COVID-19 prevention and control measures are gradually relaxed, the positive rate of respiratory pathogens in children aged from 6 months to 6 years will increase.

Nasopharyngeal colonization by Streptococcus pneumoniae in children and adults before the introduction of the 10-valent conjugate vaccine, Paraguay

Streptococcus pneumoniae is a cause of invasive diseases such as pneumonia, meningitis, and other serious infections among children and adults in Paraguay. This study was conducted to establish S. pneumoniae baseline prevalence, serotype distribution, and antibiotic resistance patterns in healthy children aged 2 to 59 months and adults ≥60 years of age prior to the introduction of PCV10 in the national childhood immunization program in Paraguay. Between April and July 2012, a total of 1444 nasopharyngeal swabs were collected, 718 from children aged 2 to 59 months and 726 from adults ≥60 years of age. The pneumococcal isolation, serotyping, and antibiotic susceptibility testing were performed using standard tests. Pneumococcal colonization prevalence was 34.1% (245/718) in children and 3.3% (24/726) in adults. The most frequent pneumococcal vaccine-types (VT) detected in the children were 6B (42/245), 19F (32/245), 14 (17/245), and 23F (20/245). Carriage prevalence with PCV10 serotypes was 50.6% (124/245) and PCV13 was 59.5% (146/245). Among colonized adults, prevalence of PCV10 and PCV13 serotypes were 29.1% (7/24) and 41.6% (10/24), respectively. Colonized children were more likely to share a bedroom, have a history of respiratory infection or pneumococcal infection compared to non-colonized children. no associations were found in adults. However, no significant associations were found in children and neither in adults. Vaccine-type pneumococcal colonization was highly prevalent in children and rare in adults in Paraguay prior to vaccine introduction, supporting the introduction of PCV10 in the country in 2012. These data will be useful to evaluate the impact of PCV introduction in the country.

Effect of pneumococcal conjugate vaccine availability on Streptococcus pneumoniae infections and genetic recombination in Zhejiang, China from 2009 to 2019

Pneumococcal pneumonia is one of the main reasons for child death worldwide. Pneumococcal conjugate vaccines (PCVs) are considered the most effective strategy for pneumococcal disease (PD) prevention, but how a pause in PCV vaccination affects the prevalence of PD or the genetic evolution of Streptococcus pneumoniae genetic evolution is unknown. Based on the unique PCV introduction timeline (vaccine unavailable during April 2015-April 2017) in China, we aimed to evaluate the effect of interrupted PCV availability on PD and pneumococcal genome variation. Pneumococcal isolates (n = 386) were collected retrospectively from eight sites in Zhejiang, China from 2009 to 2019 in which 184 pathogenic (isolates from sterile and infection sites) strains were identified. An interrupted time series analysis was conducted to estimate changes in PD and the recombination frequency of whole genome-sequenced strains was estimated via SNP calling. We found that both PD and pneumococcal genome variation were affected by interrupted PCV availability. The proportion (∼70%) of vaccine-type pneumococcal LRTI (VT-LRTI) in all LRTI cases decreased to ∼30% in the later PCV7 period and rebounded to ∼70% in children once PCV7 became unavailable in April 2015 (p = 0.0007). The major clone CC271 strains showed slowed (p = 0.0293) recombination frequency (decreased from 2.82 ± 1.16–0.72 ± 0.21) upon PCV removal. Our study illustrated for the first time that VT-LRTI fluctuated upon interrupted vaccine availability in China and causing a decreased of recombination frequency of vaccine types. Promoting a nationwide continuous vaccination programme and strengthening S. pneumoniae molecular epidemiology surveillance are essential for PD prevention.

Promising Expectations for Pneumococcal Vaccination during COVID-19

The emergence of new viral infections has increased over the decades. The novel virus is one such pathogen liable for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, popularly known as coronavirus disease 2019 (COVID-19). Most fatalities during the past century's influenza pandemics have cooperated with bacterial co/secondary infections. Unfortunately, many reports have claimed that bacterial co-infection is also predominant in COVID-19 patients (COVID-19 associated co/secondary infection prevalence is up to 45.0%). In the COVID-19 pandemic, Streptococcus pneumoniae is the most common coinfecting pathogen. Half of the COVID-19 mortality cases showed co-infection, and pneumonia-related COVID-19 mortality in patients >65 years was 23%. The weakening of immune function caused by COVID-19 remains a high-risk factor for pneumococcal disease. Pneumococcal disease and COVID-19 also have similar risk factors. For example, underlying medical conditions on COVID-19 and pneumococcal diseases increase the risk for severe illness at any age; COVID-19 is now considered a primary risk factor for pneumococcal pneumonia and invasive pneumococcal disease. Thus, pneumococcal vaccination during the COVID-19 pandemic has become more critical than ever. This review presents positive studies of pneumococcal vaccination in patients with COVID-19 and other medical conditions and the correlational effects of pneumococcal disease with COVID-19 to prevent morbidity and mortality from co/secondary infections and superinfections. It also reports the importance and role of pneumococcal vaccination during the current COVID-19 pandemic era to strengthen the global health system.

Health and economic impact of the pneumococcal conjugate vaccine in hindering antimicrobial resistance in China

Antimicrobial resistance (AMR) poses a serious threat to global public health. However, vaccinations have been largely undervalued as a method to hinder AMR progression. This study examined the AMR impact of increasing pneumococcal conjugate vaccine (PCV) coverage in China. China has one of the world's highest rates of antibiotic use and low PCV coverage. We developed an agent-based DREAMR (Dynamic Representation of the Economics of AMR) model to examine the health and economic benefits of slowing AMR against commonly used antibiotics. We simulated PCV coverage, pneumococcal infections, antibiotic use, and AMR accumulation. Four antibiotics to treat pneumococcal diseases (penicillin, amoxicillin, third-generation cephalosporins, and meropenem) were modeled with antibiotic utilization, pharmacokinetics, and pharmacodynamics factored into predicting AMR accumulation. Three PCV coverage scenarios were simulated over 5 y: 1) status quo with no change in coverage, 2) scaled coverage increase to 99% in 5 y, and 3) accelerated coverage increase to 85% over 2 y followed by 3 y to reach 99% coverage. Compared to the status quo, we found that AMR against penicillin, amoxicillin, and third-generation cephalosporins was significantly reduced by 6.6%, 10.9%, and 9.8% in the scaled scenario and by 10.5%, 17.0%, and 15.4% in the accelerated scenario. Cumulative costs due to AMR, including direct and indirect costs to patients and caretakers, were reduced by $371 million in the scaled and $586 million in the accelerated scenarios compared to the status quo. AMR-reducing benefits of vaccines are essential to quantify in order to drive appropriate investment.

Pneumococcal carriage in children with COVID-19

Background: SARS-CoV-2 is the new virus, and Streptococcus pneumoniae is one of the most important pathogens affecting humans. However, we do not yet know whether these microorganisms interact. Thus, we aimed to evaluate the relationship between Streptococcus pneumoniae and SARS-CoV-2 in pediatric patients.Methods: This study was conducted retrospectively by means of medical records of pediatric patients who were tested for SARS-CoV-2 between March 11 and June 04, 2020, in the University of Health Sciences, Ankara Educating and Training Hospital and Hacettepe University Faculty of Medicine.Results: We evaluated 829 pediatric patients for S. pneumoniae and SARS-CoV-2 from their nasopharyngeal specimen. Of 115 children positive for SARS-CoV-2, 32.2% had a positive S. pneumoniae test, whereas of 714 children negative for SARS-CoV-2, 14.1% had a positive S. pneumoniae test (p < .01). We compared patients with positive vs. negative SARS-CoV-2 tests according to S. pneumoniae positivity There were no statistically significant differences in terms of gender, underlying disease, fever, cough, leukocytosis, lymphopenia, increased CRP, increased procalcitonin, findings of chest x-ray, severity of disease, and treatment.Conclusion: The nasopharyngeal S. pneumoniae carriage rate in patients with COVID-19 was higher than in non-infected children, while S. pneumoniae carriage did not affect the course of COVID-19 disease. Pneumococcal vaccination is significant, such that we do not know the outcomes of increased pneumococcal carriage for the upcoming months of pandemic.

A longitudinal hospital-based epidemiology study to assess acute otitis media incidence and nasopharyngeal carriage in Korean children up to 24 months

This study was conducted to assess the nasopharyngeal (NP) carriage and acute otitis media (AOM) occurrence in Korean children who received pneumococcal conjugate vaccines (PCVs). The longitudinal study was conducted through four consecutive visits. At each visit, NP aspirates were obtained and subjects were asked to visit if AOM occurred. A total of 305 subjects were enrolled and received PCV13 (n = 182) or PCV10 (n = 123). In the PCV13 group, the NP carriage of Streptococcus pneumoniae at each visit was 2.7%, 14.8%, 18.7%, and 15.9%, respectively. Non-typeable Haemophilus influenzae (NTHi) was 3.3%, 2.7%, 2.7%, and 5.5%, and that of Moraxella catarrhalis was 1.1%, 9.3%, 4.9%, and 0.5%. In the PCV10 group, the NP carriage of S. pneumoniae at each visit was 3.3%, 7.3%, 6.5%, and 4.1%, respectively. That of NTHi was 2.4%, 4.1%, 1.6%, and 0.8%, and that of M. catarrhalis was 4.1%, 0.8%, 0.8%, and 0.0%. AOM occurrence in the PCV13 group observed after the primary dose and before booster dose was 20.9%, occurrence after booster dose was 11.0%, and the incidence of two or more AOM was 11.0%. In the PCV10 group, AOM occurrence was 9.8%, 7.3%, respectively, and the incidence of two or more AOM was 2.4%. The predominant S. pneumoniae isolated were non-vaccine type (10A, 15A, and 15B). In this study, AOM occurrence was lower in the PCV10 group than in the PCV13 group. This seems to be related to ecological changes that lead to differences in NP carriage, especially S. pneumoniae and NTHi.

Serotype distribution of Streptococcus pneumoniae isolated from children hospitalized in Beijing children's hospital (2013-2019)

BACKGROUND

Streptococcus pneumoniae can cause many infectious diseases among children, and relevant vaccines have not been scheduled into the National Immunization Program in China. The serotype distribution of Streptococcus pneumoniae is essential information used to evaluate the value of pneumococcal vaccines and formulate immunization strategies.

METHODS

Streptococcus pneumoniae isolates, identified as the disease pathogens, were collected from children hospitalized in Beijing Children's Hospital from 2013 to 2019. The serotype was detected by the Quellung reaction.

RESULTS

A total of 903 isolates of Streptococcus pneumoniae were collected, among which 809 were from non-invasive infections and 94 were from invasive infections. The non-invasive isolates were mainly isolated from respiratory secretions (49.4%) and bronchoalveolar lavage fluid (38.9%), while invasive isolates were from venous blood (5.4%), cerebrospinal fluid (2.8%) and pleural effusion (2.8%). The leading serotypes were 19F (36.0%), 19A (13.6%), 23F (9.4%), 14 (8.9%), 6A (6.9%), and 6B (5.3%). The overall coverage rates of 10-, 13-, 15-, 20-valent pneumococcal conjugate vaccines (PCV10, PCV13, PCV15, PCV20) and 23-valent pneumococcal polysaccharide vaccine (PPV23) as well as Pneumosil (a 10-valent pneumococcal conjugate vaccine) were 61.6%, 83.2%, 83.4%, 88.0%, 82.4% and 81.6%, respectively. The coverage rates of PCV13, PCV15 and PPV23 in isolates from invasive infections were significantly higher than those from non-invasive infections. The coverage rates of Pneumosil, either on the whole or among different age groups or different infections, were significantly higher than those of PCV10.

CONCLUSIONS

Serotypes 19F, 19A, 23F, 14, 6A and 6B were the most common types among the isolates. As for pneumococcal vaccines available now, the coverage rate of PCV13 was high, especially in isolates from invasive infections. The promotion of PCV13 or further high valent vaccines might be of greater benefit in preventing pneumococcal infections than other pneumococcal vaccines in children.

Molecular capsular typing and multi locus sequence typing of invasive, non-invasive and commensal Streptococcus pneumoniae isolates from North India

Purpose

The purpose of this study is to determine the antimicrobial susceptibility pattern, serotype distribution and sequence type (ST) of Streptococcus pneumoniae isolates from invasive and non-invasive infection and correlate it with isolates from commensal nasopharyngeal flora to ascertain their role in infection.

Materials and Methods

S. pneumoniae isolates from blood, cerebrospinal fluid, pleural fluid and respiratory secretions (sputum, bronchoalveolar lavage and nasopharyngeal swab/throat swab) were analysed to determine ST, serotype and antimicrobial susceptibility pattern. Serotyping was performed by multiplex polymerase chain reactions as well as by quellung reaction. Antimicrobial susceptibility testing was determined using Kirby Bauer's disc diffusion method as per the Clinical Laboratory Standards Institute guidelines. Minimum inhibitory concentration was determined using E-test for penicillin. Multilocus sequence typing (MLST) was done to understand genetic relatedness and evolutionary relationship among strains.

Results

A total of 125 S. pneumoniae isolates were collected, including 25 from invasive pneumococcal disease, 25 from non-invasive and 75 from nasopharyngeal swab of healthy children (Commensal). Resistance to penicillin, erythromycin, and co-trimoxazole was observed in 14.4%, 12% and 81.6% of the isolates, respectively, by KirbyBauer's disc diffusion method. Serotype 14 was found to be the most prevalent in invasive and non-invasive isolates, while serotype 6 was the most common in commensal isolates. New STs were found among invasive (ST13826, ST13827), non-invasive (ST13823, ST13824, and ST13961) and commensal (ST13825) isolates.

Conclusion

MLST sequence analysis shows that invasive isolates were found to be clustered with non-invasive and commensal isolates. Analysis of MLST suggests the possibility of genetic relatedness and exchange of genetic material between invasive, non-invasive and commensal isolates.

Nasopharyngeal pneumococcal carriage in healthy Turkish children after 13-valent conjugated pneumococcal vaccine implementation in the national immunization program

BACKGROUND

In Turkey, pneumococcal conjugated vaccine (PCV) was introduced to the national immunization program as PCV7 in 2008, and was replaced with PCV13 in 2011. The aims of this study were to investigate the effects of PCV13 on nasopharyngeal pneumococcal carriage (NPC) by determining the serotype distribution, and to identify risk factors for carriage, in healthy Turkish children.

METHODS

This prospective study was conducted on 500 healthy children aged 0-13 years between April and November 2014. Nasopharyngeal swab samples were taken, and molecular method for capsular serotyping was performed by multiplex PCR.

RESULTS

Of 500 children, 43.4% were unvaccinated with a PCV (7- or 13-valent), 56.6% were vaccinated and The NPC rate was found to be 9.8%. Of 49 positive Streptococcus pneumoniae isolates, 26 (53%) were PCV13 vaccine strains (VSs), and 17 (34.7%) were non-VS. Six isolates (12.2%) were not typeable by the method applied. The most common serotypes detected were serotype 3 (18.3%), serotype 19F (14.2%), serotype 6A/B (8.1%), serotype 11A (8.1%), and serotype 15B (8.1%). The total coverage rate of the PCV13 serotypes was 60.4%.

CONCLUSION

A significant decrease in carriage rate was detected within three years after the introduction of PCV13 in Turkey. However, the nasopharyngeal carriage of PCV13 strains was found to be interestingly high.

Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae causing invasive diseases in China: a meta-analysis

Background

To summarize information about invasive pneumococcal disease (IPD) among children in mainland China.

Methods

Sixteen eligible studies were included in this systematic review and the random effect model was used to estimate the pool prevalence of IPD.

Results

The most predominant serotypes circulating in children were 19F (27.7, 95% confidence interval (95% CI): 17.7–37.6%), 19A (21.2%, 16.4–26.1%), 14 (16.5%, 12.8–20.1%), 6B (8.6%, 5.2–10.8%) and 23F (7.3%, 5.2–9.5%). The serotype coverage of the available pneumococcal conjugate vaccines PCV7, PCV10, and PCV13 was 60.8% (52.5–69.4%), 65.1% (57.7–72.4%), and 90.0% (87.1–92.8%), respectively. The pooled antibiotic resistance rates of Streptococcus pneumoniae revealed a resistance to penicillin prevalence rate of 32.0% (12.1–51.9%). Approximately 94.4% (90.7–98.1%) and 92.3% (87.4–97.3%) of isolates were resistant to erythromycin and clindamycin. eBURST analysis revealed great diversity among isolates, with 102 sequence types (STs) for 365 isolates. The major predominant clonal complexes (CCs) were CC271 (43.6%, 159/365), CC876 (13.4%, 49/365), CC81 (5.2%, 19/365), and CC90 (4.1%, 15/365). Long-term and regional surveillance of S. pneumoniae is necessary.

Conclusions

Based on our pooled results showing that PCV13 coverage of the reported serotypes was 90% and that most serotypes contributed to the distribution of antibiotic-resistant isolates, implementation of PCV13 into the Chinese Expanded Program on Immunizations (EPI) would achieve health benefits in Chinese children.