ABSTRACT
Respiratory tract infections (RTIs) have a significant impact on global health, especially among children and the elderly. The key bacterial pathogens Streptococcus pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae, Staphylococcus aureus and non-fermenting Gram Negative bacteria such as Acinetobacter baumannii and Pseudomonas aeruginosa are most commonly associated with RTIs. These bacterial pathogens have evolved a diverse array of resistance mechanisms through horizontal gene transfer, often mediated by mobile genetic elements and environmental acquisition. Treatment failures are primarily due to antimicrobial resistance and inadequate bacterial engagement, which necessitates the development of alternative treatment strategies. To overcome this, our review mainly focuses on different virulence mechanisms and their resulting pathogenicity, highlighting different therapeutic interventions to combat resistance. To prevent the antimicrobial resistance crisis, we also focused on leveraging the application of artificial intelligence and machine learning to manage RTIs. Integrative approaches combining mechanistic insights are crucial for addressing the global challenge of antimicrobial resistance in respiratory infections.
Subject(s)
Anti-Bacterial Agents , Respiratory Tract Infections , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/drug therapy , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteria/genetics , Bacteria/drug effects , Bacteria/classification , Drug Resistance, Bacterial , Bacterial Infections/microbiology , Bacterial Infections/drug therapy , VirulenceABSTRACT
In mice, γδ-T lymphocytes that express the co-stimulatory molecule, CD27, are committed to the IFNγ-producing lineage during thymic development. In the periphery, these cells play a critical role in host defense and anti-tumor immunity. Unlike αß-T cells that rely on MHC-presented peptides to drive their terminal differentiation, it is unclear whether MHC-unrestricted γδ-T cells undergo further functional maturation after exiting the thymus. Here, we provide evidence of phenotypic and functional diversity within peripheral IFNγ-producing γδ T cells. We found that CD27+ Ly6C- cells convert into CD27+Ly6C+ cells, and these CD27+Ly6C+ cells control cancer progression in mice, while the CD27+Ly6C- cells cannot. The gene signatures of these two subsets were highly analogous to human immature and mature γδ-T cells, indicative of conservation across species. We show that IL-27 supports the cytotoxic phenotype and function of mouse CD27+Ly6C+ cells and human Vδ2+ cells, while IL-27 is dispensable for mouse CD27+Ly6C- cell and human Vδ1+ cell functions. These data reveal increased complexity within IFNγ-producing γδ-T cells, comprising immature and terminally differentiated subsets, that offer new insights into unconventional T-cell biology.
Subject(s)
Antigens, Ly , Receptors, Antigen, T-Cell, gamma-delta , Tumor Necrosis Factor Receptor Superfamily, Member 7 , Animals , Mice , Antigens, Ly/metabolism , Antigens, Ly/genetics , Tumor Necrosis Factor Receptor Superfamily, Member 7/metabolism , Tumor Necrosis Factor Receptor Superfamily, Member 7/genetics , Tumor Necrosis Factor Receptor Superfamily, Member 7/immunology , Humans , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Antigen, T-Cell, gamma-delta/genetics , Interferon-gamma/metabolism , Interferon-gamma/immunology , Interleukin-27/metabolism , Interleukin-27/genetics , Cell Differentiation/immunology , Mice, Inbred C57BL , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolismABSTRACT
BACKGROUND: Neonatal sepsis poses a critical healthcare concern, as multidrug-resistant Klebsiella pneumoniae ( K. pneumoniae ) infections are on the rise. Understanding the antimicrobial susceptibility patterns and underlying resistance mechanism is crucial for effective treatment. OBJECTIVES: This study aimed to comprehensively investigate the antimicrobial susceptibility patterns of K. pneumoniae strains responsible for neonatal sepsis using in silico tools. We sought to identify trends and explore reasons for varying resistance levels, particularly for ß-lactams and fluoroquinolone. METHODS: K. pneumoniae isolated from neonates at Kanchi Kamakoti CHILDS Trust Hospital (2017-2020) were analyzed for antimicrobial resistance. Elevated resistance to ß-lactam and fluoroquinolone antibiotics was further investigated through molecular docking and interaction analysis. ß-lactam affinity with penicillin-binding proteins and ß-lactamases was examined. Mutations in ParC and GyrA responsible for quinolone resistance were introduced to investigate ciprofloxacin interactions. RESULTS: Of 111 K. pneumoniae blood sepsis isolates in neonates, high resistance was detected to ß-lactams such as cefixime (85.91%, n = 71), ceftriaxone (84.9%, n = 106), cefotaxime (84.9%, n = 82) and fluoroquinolone (ciprofloxacin- 79.44%, n = 107). Molecular docking revealed low ß-lactam binding toward penicillin-binding proteins and higher affinities for ß-lactamases, attributing to the reduced ß-lactam efficiency. Additionally, ciprofloxacin showed decreased affinity toward mutant ParC and GyrA in comparison to their corresponding wild-type proteins. CONCLUSION: Our study elucidates altered resistance profiles in neonatal sepsis caused by K. pneumoniae , highlighting mechanisms of ß-lactam and fluoroquinolone resistance. It underscores the urgent need for the development of sustainable therapeutic alternatives to address the rising antimicrobial resistance in neonatal sepsis.
Subject(s)
Anti-Bacterial Agents , Drug Resistance, Multiple, Bacterial , Klebsiella Infections , Klebsiella pneumoniae , Microbial Sensitivity Tests , Molecular Docking Simulation , Neonatal Sepsis , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/genetics , Humans , Infant, Newborn , Neonatal Sepsis/drug therapy , Neonatal Sepsis/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Klebsiella Infections/drug therapy , Klebsiella Infections/microbiology , Drug Resistance, Multiple, Bacterial/genetics , Computer Simulation , beta-Lactams/pharmacology , Fluoroquinolones/pharmacology , Fluoroquinolones/therapeutic use , beta-Lactamases/genetics , beta-Lactamases/metabolismABSTRACT
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) continues to challenge the global healthcare with emerging variants and higher infectivity as well as morbidities. This study investigated potential age-related variations through genomic characterization of the virus under common clinical settings. A cohort comprising 71 SARS-CoV-2 strains from both infected infants and accompanying adults, diagnosed via RT-PCR at a tertiary pediatric hospital and research center, underwent Illumina paired-end sequencing. The subsequent analysis involved standard genomic screening, phylogeny construction, and mutational analyses. The analyzed SARSCoV- 2 strains were compared with globally circulating variants. The overall distribution revealed 67.61 % Delta, 25.7 % Omicron, and 1 % either Kappa or Alpha variants. In 2021, Delta predominated at â¼ 94 %, with Alpha/Kappa accounting for around 5 %. However, in 2022, over 94 % of the samples were Omicron variants, signifying a substantial shift from Delta dominance. Delta variants constituted 69.5 % of infections in adults and 78.5 % in infants, while Omicron variants were responsible for 31 % of cases in infants and 18 % in adults. The Spike region harbored the majority of mutations, with T19R being the most prevalent mutation in the Delta lineage. Notably, the frequencies of this mutation varied between infants and adults. In Omicron samples, G142D emerged as the most prevalent mutation. Our dataset predominantly featured clade 21A and lineage B.1.617.2. This study underscores the differential clinical presentations and genomic characteristics of SARS-CoV-2 in pediatric patients and accompanying adults. Understanding the dynamic evolution of the SARS- CoV-2 in both pediatric and adults can help in strengthening prophylactic measures.
Subject(s)
COVID-19 , Genome, Viral , Mutation , Phylogeny , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/virology , COVID-19/genetics , Infant , Adult , Child , Child, Preschool , Whole Genome Sequencing/methods , Female , Male , Adolescent , Middle Aged , Spike Glycoprotein, Coronavirus/genetics , Young AdultABSTRACT
FtsZ, a bacterial cell division protein, is essential for assembling the contractile Z-ring crucial in bacterial cytokinesis. Consequently, inhibiting FtsZ could impede proto-filaments, disrupting FtsZ and other associated proteins vital for cell division machinery. Conduct an in-silico drug interaction study to identify novel drug candidates that inhibit the FtsZ protein, aiming to prevent Multi-Drug Resistant (MDR) Salmonella Typhi. Data mining was performed based on piperidine compounds, which were subsequently screened for safe pharmacokinetic profiles. Compounds that met favorable drug-likeness criteria underwent virtual screening against the FtsZ drug target. Two compounds were chosen for molecular docking and molecular dynamic simulation to verify the binding affinity and stability between the target protein and the potential compounds. The 400 isoforms of piperidine analogues were curated, among them potent compound ZINC000000005416 found to possess high binding affinity (-8.49 kcal/mol) and low dissociation constant (0.597 µM). The highest binding affinity shown by ZINC000000005416 was validated by hydrogen bonds, hydrophobic interaction, and salt bridges with the functional domain of the cell division regulatory protein. Docking profiles, when correlated with molecular dynamic simulation (MDS) depicted stable trajectories and compatible conformational changes in the FtsZ-ZINC000000005416 complex. The stable simulated trajectories were validated through free-energy calculations using the Molecular Mechanics-Poisson Boltzmann Surface Area (MM/PBSA) module. Low energy conformations, although the simulation trajectory confirmed the stable ZINC000000005416-FtsZ interaction, which encouraged experimental validations. This study encourages further exploration of the compound ZINC000000005416 as a drug candidate inhibiting FtsZ protein against MDR Salmonella Typhi.Communicated by Ramaswamy H. Sarma.
ABSTRACT
Background: Strong associations between early antibiotic exposure and increased risk of childhood allergies have been established. Antibiotics have the potential to induce microbial dysbiosis that may be linked to allergic conditions. This review examines the limited available evidence on the associations between adult antibiotic use, microbial dysbiosis and atopic conditions. Methods: A systematic literature search was conducted using PubMed and Embase for relevant studies, published between 01-01-2000 and 08-17-2022. We searched for associations between antibiotic use, microbial dysbiosis, and allergic conditions in adults, defined as over 13 years of age for the purposes of this review. Results: Twenty-one studies were analyzed, with the inclusion of four narrative reviews as scarce relevant literature was found when stricter selection criteria were employed. Relevant studies predominantly focused on asthma. Significant microbial differences were observed in most measures between healthy subjects and subjects with allergic conditions. However, no system-wise and strain-wise associations were evident. Notably, at the phyla level, the Bacillota and Pseudomonadota phyla were associated with asthmatics, while the Actinobacteria phylum was linked to healthy controls. Asthmatics tends to reflect upregulation in the Bacillota and Pseudomonadota phyla in both airway and gut microbiomes. Conclusion: No compelling evidence could be found between adult antibiotic exposure, consequent microbial dysbiosis, and allergic conditions in adults. Our review is limited by scarce literature and therefore remains inconclusive. However, potential implications of antibiotic use impacting on allergic conditions justify additional research and heightened pharmacovigilance in this area.
ABSTRACT
Public health/risk communication is the foremost responsibility of a government during a pandemic. Risk communication aims to educate people, enhance their risk perceptions to help them engage and understand the benefits of compliance with recommendations. The existing legal enforcement of recommendations in India is criticized for failing to influence the public's compliance. While existing research provides conceptual and empirical support in explaining compliance during COVID-19, we note a lack of studies that might bring out country-specific areas of improvement. We argue that value-aligned risk communication is more likely to influence the public's behavioral intentions to adopt the government's recommendations. We employed a triangulation mixed-method study to link risk communication attributes to the public's end goals and values. We triangulate these findings using the COVID score survey. We found that timeliness and transparency constitute risk communication's functional component, and empathy and trust constitute risk communication's emotional component. We found a difference in the preference of functional and emotional components among the public and health partners. Irrespective of this divide in perception, the study found that both groups unanimously noted engagement as the crucial aspect for empowerment and involvement to aid the public in teaming with the government to combat the pandemic effectively.
Subject(s)
COVID-19 , Health Communication , Humans , COVID-19/epidemiology , Public Health , Communication , Disease Outbreaks/prevention & control , India/epidemiologyABSTRACT
BACKGROUND: Acute undifferentiated fever (AUF) ranges from self-limiting illness to life-threatening infections, such as sepsis, malaria, dengue, leptospirosis and rickettsioses. Similar clinical presentation challenges the clinical management. This study describes risk factors for death in patients hospitalized with AUF in India. METHODS: Patients aged ≥5 y admitted with fever for 2-14 d without localizing signs were included in a prospective observational study at seven hospitals in India during 2011-2012. Predictors identified by univariate analysis were analyzed by multivariate logistic regression for survival analysis. RESULTS: Mortality was 2.4% (37/1521) and 46.9% (15/32) died within 2 d. History of heart disease (p=0.013), steroid use (p=0.011), altered consciousness (p<0.0001), bleeding (p<0.0001), oliguria (p=0.020) and breathlessness (p=0.015) were predictors of death, as were reduced Glasgow coma score (p=0.005), low urinary output (p=0.004), abnormal breathing (p=0.006), abdominal tenderness (p=0.023), leucocytosis (p<0.0001) and thrombocytopenia (p=0.001) at admission. Etiology was identified in 48.6% (18/37) of fatal cases. CONCLUSIONS: Bleeding, cerebral dysfunction, respiratory failure and oliguria at admission, suggestive of severe organ failure secondary to systemic infection, were predictors of death. Almost half of the patients who died, died shortly after admission, which, together with organ failure, suggests that delay in hospitalization and, consequently, delayed treatment, contribute to death from AUF.
Subject(s)
Malaria , Scrub Typhus , Sepsis , Humans , Hospitals, Community , Oliguria , Fever/etiology , Risk Factors , Malaria/diagnosis , Sepsis/complications , India/epidemiology , Scrub Typhus/diagnosisABSTRACT
Whole genome sequences of Salmonella enterica subspecies enterica serovar Typhi (S. Typhi) and Salmonella enterica subspecies enterica serovar Paratyphi A (S. Paratyphi A) from pediatric settings were used to assess the emerging Antimicrobial Resistance (AMR). The high throughput sequences of twenty pediatric clinical isolates of S. Typhi and S. Paratyphi A were retrieved and were screened for prevalent Antimicrobial Resistance Genes (ARGs) and Virulent Factors (VF). The resistance data was compared with the reference strains of S. Typhi and S. Paratyphi A. AMR studies identified sul1, sul2, dfrA7, tem-1, AH(6)-Id and APH(3â³)-Ib as common ARGs. VFs were identified to understand the level of pathogenicity. The most prevalent AMR genes in the sequenced genomes were detected in phenotypically azithromycin-resistant S. Typhi. Correlation with the global genomes projected a trend of concurrent resistance to macrolides, ß lactams, fluoroquinolones (FQs), tetracyclines, ansamycins, and aminoglycosides. Traces of sulphonamide-resistance were observed indicating the emergence of a currently non-prevalent S. Typhi resistance that could be a future threat. Hence new antibiotic regimen to treat azithromycin-resistant S. Typhi should be formulated by avoiding the risks of aggravating sulphonamide resistance. The identified ARGs in genomes from paediatric isolates will aid future studies to design anti-bacterial compounds against S. Typhi and S. Paratyphi A.
Subject(s)
Salmonella typhi , Typhoid Fever , Humans , Child , Salmonella typhi/genetics , Azithromycin/pharmacology , Typhoid Fever/microbiology , Salmonella paratyphi A/genetics , Anti-Bacterial Agents/pharmacology , Sulfanilamide , Genomics , Microbial Sensitivity Tests , Drug Resistance, Bacterial/geneticsABSTRACT
BACKGROUND: Enteric fever caused by Salmonella enterica serovar typhi and Salmonella enterica serovar paratyphi A remains one of the most common causes of community-acquired bloodstream infection among children in India. Multidrug resistance is emerging and is a cause of concern as it affects the choice of treatment in enteric fever. METHOD: In this study, a 10-year analysis of resistance patterns was done along with in-silico homology modeling and molecular docking to understand the commonly occurring quinolone resistance. RESULTS: A total of 1010 cases of blood culture-confirmed enteric fevers (S. typhi n=849; S. paratyphi A n=161) were recorded at the study hospital during the period from 2011-2020. Multidrug resistance among cases of S. typhi was 2.12 %, whereas it was completely absent among cases of S. paratyphi A. Fluoroquinolone resistance was high (>95%) throughout the study period. Resistance to ampicillin, chloramphenicol and co-trimoxacole was low (<3%) among S. typhi cases. No deaths were observed among study participants. Molecular docking analysis showed that quinolone had less binding affinity to mutated gyrase A than to its wild type for both S. typhi and S. paratyphi A. CONCLUSION: Quinolone resistance was high among cases of enteric fever, whereas no resistance was observed among third-generation cephalosporins. In-silico studies indicated that a mutation in gyrase A might be the cause of the gradual increase in ciprofloxacin resistance over the study period.
Subject(s)
Quinolones , Salmonella enterica , Typhoid Fever , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Child , Drug Resistance, Bacterial/genetics , Drug Resistance, Multiple , Hospitals, Pediatric , Humans , India/epidemiology , Microbial Sensitivity Tests , Molecular Docking Simulation , Quinolones/therapeutic use , Salmonella enterica/genetics , Salmonella typhi/genetics , Serogroup , Typhoid Fever/drug therapy , Typhoid Fever/epidemiologyABSTRACT
Streptococcus pneumoniae is the major cause of childhood pneumonia and related deaths in India. Widespread use of erythromycin for the treatment of pneumonia has led to the emergence of erythromycin resistance. Despite this increase in erythromycin resistance, there are very little data on resistance determinants from India. Hence, we aimed to perform the molecular characterization of erythromycin-resistant invasive pneumococcal isolates in India. In this study, 250 erythromycin-resistant invasive isolates obtained from four Indian hospitals between 2014 and 2019 were included. The isolates were reconfirmed by standard CDC protocols, followed by detection of erm(B), mef(A/E) genes, and screening for mutations in 23S rRNA, ribosomal proteins L4 and L22. Among the 250 erythromycin-resistant isolates, 46% (n = 114) and 35% (n = 87) carried the mef(A/E) gene and erm(B) gene, respectively; both genes were present in 8% (n = 20) of the isolates and 12% (n = 29) of the studied strains did not bear any of them. The major mutations associated with erythromycin resistance in 23S rRNA, such as A2060C, A2061G, and C2613G, were absent. The predominant serotypes were 19F, 14, 23F, 6A, 6B, 19A, and 9V. The major clonal complexes were CC320, followed by CC230 and CC63. The predominant gene was mef(A/E), and most of the serotypes were PCV13 (54%). This study contributes to the baseline understanding of the erythromycin resistance determinants associated with the serotypes and sequence types (ST) of Indian invasive S. pneumoniae.
Subject(s)
Pneumococcal Infections , Streptococcus pneumoniae , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/genetics , Erythromycin/pharmacology , Humans , India , Microbial Sensitivity Tests , Serogroup , Serotyping , Streptococcus pneumoniae/geneticsABSTRACT
INTRODUCTION: Children usually present with minimal or no symptoms of COVID-19 infection. Antibody responses to SARS-CoV-2 in children from low- and middle-income countries (LMIC) have not been well described. We describe the prevalence of anti-SARS-CoV-2 antibodies and clinical phenotype of seropositive children admitted to a tertiary children's hospital in South India. METHODS: To determine the seropositivity and describe the clinical characteristics of COVID-19 infection amongst hospitalised children, we performed a prospective clinical data collection and blood sampling of children admitted to Kanchi Kamakoti CHILDS Trust Hospital, Chennai, India over 4 months of the COVID-19 pandemic. In seropositive children, we compared antibody titres between children with and without PIMS-TS. RESULTS: Of 463 children, 91 (19.6%) were seropositive. The median (range) age of seropositive children was 5 years (1 month-17 years). Clinical presentation was consistent with Paediatric inflammatory multisystem syndrome associated or related with SARS-CoV-2 infection (PIMS-TS) in 48% (44/91) of seropositive children. The median (range) antibody titre was 54.8 (11.1-170.9) AU/ml among all seropositive children. The median antibody titre among the children with PIMS-TS (60.3 AU/mL) was significantly (p = 0.01) higher when compared to the children without PIMS-TS (54.8 AU/mL). CONCLUSION: We describe the antibody responses to SARS-CoV-2 amongst hospitalised children in a LMIC tertiary children's hospital. Almost half of the seropositive children had PIMS-TS. Antibody levels may be helpful in the diagnosis and disease stratification of PIMS-TS. LAY SUMMARY: Children usually present with minimal or no symptoms of COVID-19 infection. However, Multisystem Inflammatory Syndrome in Children (MIS-C) or Paediatric inflammatory multisystem syndrome associated or related with SARS-CoV-2 infection (PIMS-TS) has emerged as a distinctive paediatric illness related to SARS-CoV-2. Recently, antibody testing for SARS-CoV-2 is being used increasingly as a diagnostic test for PIMS-TS. However, data on the antibody responses to SARS-CoV-2 in children are sparse. We, therefore, attempted to identify the seropositivity and describe the clinical spectrum of COVID-19 infection amongst infants and children getting hospitalised in a children's hospital in south India. Nearly one-fifth of the hospitalised children tested serology positive over 4 months. Antibody levels in children with PIMS-TS were significantly higher in comparison to the other two groups (acute COVID-19 infection and children without PIMS-TS). Results from our study suggest that all children are at risk of COVID-19 infection though they may present with mild illness or no symptoms. We also observed that antibody testing may have a possible role in diagnosis of PIMS-TS.
Subject(s)
COVID-19/complications , SARS-CoV-2 , Systemic Inflammatory Response Syndrome/epidemiology , COVID-19/epidemiology , Child , Child, Hospitalized , Child, Preschool , Humans , India/epidemiology , Infant , Pandemics , Phenotype , Prospective Studies , Systemic Inflammatory Response Syndrome/diagnosisSubject(s)
COVID-19 Serological Testing , COVID-19/diagnosis , Child , Hospitals , Humans , India , Secondary CareABSTRACT
Primary Caregivers are the fulcrum in the physician-caregiver-child triad. Existing literature discusses static multi-component interventions in detail. In long-term treatments, dynamic intervention design is needed as the environment and situations of the families are dynamic. The objectives of this study are (a) to identify the components of the primary caregiver's perception of the physician's value with reference to the effectiveness of consultation and relationships with the former and with the child; (b) to establish the role of this perception in designing dynamic interventions, and (c) to describe the perception's potential influence on adherence. A PRISMA, chronological, and morphological analysis of the literature is carried out about caregivers' adherence in the pediatric long-term treatment context. We define communication and consultation as the functional, whereas relationship as the emotional component of the caregiver's perception of the physician. We propose a theoretical model that incorporates intervention as an integral component of care. Adherence happens as a response to changing situations and hence fluctuates. Hence, a dynamic intervention design to benefit the child should be incorporated into care through the caregiver-physician bridge. Future research should explore how intervention needs change and the driving reasons for understanding the static and dynamic components of interventions.
Subject(s)
Caregivers , Physicians , Communication , Family , HumansABSTRACT
Objective: Molecular detection and serotyping are rapid, sensitive and accurate techniques for early diagnosis of paediatric dengue. The present study evaluates multiplex real-time polymerase chain reaction (PCR) for diagnosis of dengue virus in children hospitalised with severe dengue (SD) and attempts to establish an association of clinical severity with specific serotypes. Methods: Four hundred and eighty-five samples were received from hospitalised paediatric patients with suspected dengue from March 2019 to February 2020. Multiplex real time PCR was employed for diagnosis. An in-house real-time PCR that combined diagnosis and serotyping was established. Non-structural protein 1 (NS1) assay and real-time PCR were assessed for their accuracy in diagnosing severe paediatric dengue. Results: Three hundred and twenty-five (67%) patients were positive for dengue RNA by real-time PCR. All four serotypes were identified throughout the year; dengue serotype 2 (DEN-2) was predominant (61%) followed by DEN-3, 20%. Compared to the commonly used NS1 testing, multiplex real-time PCR showed greater sensitivity in diagnosing SD. Conclusions: Compared to NS1, multiplex real-time PCR is a rapid and accurate diagnostic test for children hospitalised with SD. DEN-2 was the predominant serotype in severe cases. Continued surveillance of serotypes should be carried out year-round in endemic areas.
Subject(s)
Dengue Virus/classification , Dengue Virus/isolation & purification , Dengue/diagnosis , Multiplex Polymerase Chain Reaction , Adolescent , Child , Child, Preschool , Dengue/epidemiology , Dengue/virology , Female , Humans , India/epidemiology , Infant , Male , Serotyping/methods , Serotyping/standards , Severity of Illness IndexABSTRACT
BACKGROUND: Streptococcus pneumoniae is a major cause of pneumonia, meningitis, and other serious infections among children in India. India introduced the 13-valent pneumococcal conjugate vaccine (PCV) in several states in 2017, and is expected to expand to nationwide coverage in the near future. To establish a baseline for measuring the impact of PCV in India, we assessed overall and serotype-specific nasopharyngeal carriage in two pediatric populations. METHODS: A cross-sectional study was conducted in Palwal District, Haryana, from December 2016 to July 2017, prior to vaccine introduction. Children 2-59 months of age with clinical pneumonia seeking healthcare and those in the community with no clear illness were targeted for enrollment. A nasopharyngeal swab was collected and tested for pneumococcus using conventional culture and sequential multiplex PCR. Isolates were tested for antimicrobial resistance using an E test. Children were considered colonized if pneumococcus was isolated by culture or PCR. The prevalence of pneumococcal and serotype-specific colonization was compared between groups of children using log-binomial regression. RESULTS: Among 601 children enrolled, 91 had clinical pneumonia and 510 were community children. The proportion colonized with S. pneumoniae was 74.7 and 54.5% among children with clinical pneumonia and community children, respectively (adjusted prevalence ratio: 1.38; 95% confidence interval: 1.19, 1.60). The prevalence of PCV13 vaccine-type colonization was similar between children with clinical pneumonia (31.9%) and community children (28.0%; p = 0.46). The most common colonizing serotypes were 6A, 6B, 14, 19A, 19F, and 23F, all of which are included in the PCV13 vaccine product. Antimicrobial resistance to at least one drug was similar between isolates from children with clinical pneumonia (66.1%) and community children (61.5%; p = 0.49); while resistance to at least two drugs was more common among isolates from children with clinical pneumonia (25.8% vs. 16.4%; p = 0.08). Resistance for all drugs was consistently higher for PCV13 vaccine-type serotypes compared to non-vaccine serotypes in both groups. CONCLUSION: This study provides baseline information on the prevalence of serotype-specific pneumococcal colonization among children prior to the introduction of PCV in India. Our results suggest a role for pneumococcal vaccines in reducing pneumococcal colonization and antimicrobial resistant isolates circulating in India.
Subject(s)
Carrier State/microbiology , Pneumococcal Infections/microbiology , Pneumococcal Vaccines/immunology , Streptococcus pneumoniae/immunology , Anti-Bacterial Agents/pharmacology , Carrier State/epidemiology , Child, Preschool , Cross-Sectional Studies , Drug Resistance, Bacterial , Female , Humans , India/epidemiology , Infant , Male , Microbial Sensitivity Tests , Nasopharynx/microbiology , Pneumococcal Infections/epidemiology , Prevalence , Serogroup , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/genetics , Vaccines, ConjugateABSTRACT
OBJECTIVES: To investigate the difference in pneumococcal carriage, acquisition, antibiotic resistance profiles and serotype distribution, in human immunodeficiency virus (HIV) affected and unaffected families. METHODS: A prospective cohort study was conducted in children with and without HIV in West Bengal from March 2012 through August 2014, prior to 13-valent pneumococcal conjugate vaccine (PCV-13) immunization. One thousand four hundred forty one nasopharyngeal swabs were collected and cultured at five-time points from children and their parents for pneumococcal culture, and serotyping by Quellung method. RESULTS: One hundred twenty five HIV infected children and their parents, and 47 HIV uninfected children and their parents participated. Two hundred forty pneumococcal isolates were found. In children under 6 y, the point prevalence of colonization was 31% in children living with HIV (CLH) and 32% in HIV uninfected children (HUC), p = 0.6. The most common vaccine type (VT) serotypes were 6A, 6B and 19A. All isolates from parents and 71% from children in the HIV uninfected cohort were PCV-13 representative, compared to 33% of isolates from CLH and their parents. Acquisition rate in children was 1.77 times that of parents (OR = 1.77, 95%CI: 1.18-2.65). The HIV status of child or parent did not affect acquisition. Isolates from CLH were more frequently resistant to multiple antibiotics (p = 0.02). CONCLUSIONS: While the rate of pneumococcal carriage and acquisition did not differ between CLH and HUC, HIV affected families had exposure to a wider range of serotypes including non-vaccine type serotypes and antibiotic resistant serotypes, than HIV unaffected families.
Subject(s)
Carrier State/microbiology , HIV Infections/complications , Pneumococcal Infections/microbiology , Pneumococcal Vaccines/administration & dosage , Streptococcus pneumoniae/pathogenicity , Child , Child, Preschool , Female , HIV Infections/epidemiology , HIV Infections/microbiology , Humans , India , Longitudinal Studies , Male , Microbial Sensitivity Tests , Nasopharynx/microbiology , Parents , Pneumococcal Infections/epidemiology , Pneumococcal Infections/transmission , Pneumococcal Infections/virology , Prevalence , Prospective Studies , Serogroup , Serotyping , Streptococcus pneumoniae/immunology , VaccinationABSTRACT
The hyperpolarization technique, Signal Amplification by Reversible Exchange (SABRE), has the potential to improve clinical diagnosis by making molecular magnetic resonance imaging inâ vivo a reality. Essential to this goal is the ability to produce a biocompatible bolus for administration. We seek here to determine how the identity of the catalyst and substrate affects the cytotoxicity by inâ vitro study, in addition to reporting how the use of biocompatible solvent mixtures influence the polarization transfer efficiency. By illustrating this across five catalysts and 8 substrates, we are able to identify routes to produce a bolus with minimal cytotoxic effects.
Subject(s)
Biocompatible Materials/chemistry , Antitubercular Agents/chemistry , Antitubercular Agents/pharmacology , Biocompatible Materials/metabolism , Catalysis , Cell Line, Tumor , Cell Survival/drug effects , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Deuterium/chemistry , Humans , Iridium/chemistry , Isoniazid/chemistry , Isoniazid/pharmacology , Methane/analogs & derivatives , Methane/chemistry , Pyrazinamide/chemistry , Pyrazinamide/pharmacology , Substrate SpecificityABSTRACT
[This corrects the article DOI: 10.1371/journal.pone.0158816.].
ABSTRACT
Streptococcus pneumoniae continues to take a heavy toll on childhood mortality and morbidity across the developing world. An estimated 10.6 million invasive pneumococcal diseases (IPDs) occur every year, with nearly 1 million deaths in children under 5 years of age. Introduction of vaccines in the childhood immunisation programme in developed world has brought down the incidence of the disease considerably. However, childhood immunocompromising illnesses including HIV have increased the risk of IPD several folds. There is also a growing concern on the increasing antibiotic resistance among these invasive strains to penicillin, other beta-lactams and macrolides, making treatment difficult and expensive. It is estimated that about 62% of IPD worldwide is caused by the 10 most common serotypes. Although the ranking of individual pneumococcal serotypes causing serious disease varies among nations, the 7-13 serotypes included in pneumococcal conjugate vaccines (PCVs) may prevent 50%-80% of all paediatric pneumococcal diseases globally. The World Health Organization has recommended the use of PCV-10/13 in the national immunisation programmes (NIPs) of developing countries. Four doses of PCV-13 have been recommended by the US Association of Pediatrics and Centers for Disease Control and Prevention, at intervals of each 2 months for the first 6 months and by the 12th to 15th months after birth. This is expected to reduce the morbidity and mortality associated with IPD and simultaneously decrease colonisation with circulating antibiotic-resistant strains in immunized communities. Nevertheless, continued surveillance of antimicrobial resistance in non-vaccine serotypes is necessary to prevent the resurgence of resistance. Other virulence factors which are not serotype specific also need to be studied to overcome the drawbacks of serotype-specific pneumococcal vaccines. PCV-13 was launched during May 2017 under the NIP of five Indian states with the highest pneumococcal diseases in the country and is expected to be rolled out in the other parts of the country in the coming days.