The impact of vaccination on the burden of invasive pneumococcal disease from a nationwide surveillance program in Lebanon: an unexpected increase in mortality driven by non-vaccine serotypes.

BACKGROUND: The impact of pneumococcal conjugate vaccines (PCVs) on the burden of invasive pneumococcal disease (IPD) and serotype distribution was examined across age groups from data collected by the Lebanese Inter-Hospital Pneumococcal Surveillance Program. METHODS: Between 2005 and 2020, 593 invasive Streptococcus pneumoniae isolates were collected from 79 hospitals throughout Lebanon. Serotypes and antimicrobial resistance (AMR) profiles were identified, and trends compared over 3 eras: PCV7, post-PCV7/ pre-PCV13, and PCV13 eras. RESULTS: The prevalence of PCV7 serotypes decreased significantly from 43.6% in the PCV7 era to 17.8% during the PCV13 era (p<0.001). PCV13-only serotypes remained stable in the PCV13 compared to the post-PCV7 eras, especially serotypes 1 and 3, whereas non-vaccine types (NVT) increased throughout the study period, especially 24 and 16F. The mortality rate increased substantially from 12.5% (PCV7 era) to 24.8% (PCV13 era). A significant decrease in AMR was observed across the three study eras. CONCLUSION: PCVs substantially impacted IPD and AMR in vaccinated and unvaccinated populations despite an increase in mortality driven by NVT. Broadening the recommendation of vaccination to include older age-groups, using higher valency vaccines, and implementing stringent antimicrobial stewardship are likely to further impact the burden of IPD.

Wide Variability in the Sensitivity and Specificity of Rotavirus Immunoassay Diagnostic Kits in Practice.

INTRODUCTION: Most hospitals rely on rapid antigen-detection kits for the diagnosis of rotavirus infection. Several small studies reviewed the sensitivity and specificity of some of these kits. These studies showed discrepancy in results obtained for sensitivity and specificity that varied according to the type of kit used, area of study, and type of test used as standard for diagnosis of rotavirus infection. The objective of the study is to determine the sensitivity and specificity of five commonly used rotavirus immunoassay kits in comparison to RT-PCR as standard. METHODOLOGY: Stool samples (N = 1,414) collected from children under 5 years of age hospitalized with gastroenteritis were tested for rotavirus by immunoassay kits and RT-PCR in a prospective hospital-based surveillance study conducted at 7 centers in Lebanon. Concordance and discrepancy between the two methods was used to calculate sensitivity and specificity, using RT-PCR as the "gold standard". RESULTS: The sensitivity and specificity were respectively 95.08% and 86.62% for the SD Bioline® (Standard Diagnostics, Inc, South Korea) kit calculated on 645 samples, 65.86% and 45.90% for the VIROTECT® (Trinity Biotech, Ireland) kit calculated on 327 samples, 83.9% and 64.2% for the Rota-Strip (C-1001) (Coris Bioconcept, Belgium) calculated on 95 samples, 52.3% and 10.9% for the Acon® (Acon Laboratories, Inc, California, USA) kit calculated on 122 samples, 68.1% and 20% for the VIKIA® Rota-Adéno (Biomerieux, France) kit calculated on 32 samples. CONCLUSION: A wide discrepancy was detected between the calculated and advertised sensitivity and specificity for most of the kits.

Placement of Labcor Pulmonary Conduit Results in a High Incidence of Postoperative Fever.

BACKGROUND: Fever in the postoperative period in cardiac patients is common. The purpose of this study is to recognize the risk factors for prolonged postoperative fever in cardiac patients with pulmonary conduit insertion. METHODS: Patients were identified retrospectively by looking at the International Classification of Diseases, Ninth Revision, Clinical Modification procedure code for pulmonary conduit insertion between June 2009 and December 2015 at the American University of Beirut Medical Center. Data about preoperative, perioperative, and postoperative variables were collected. Data entry and analysis were performed using SPSS version 22. RESULTS: The study identified 59 patients. The most common type of pulmonary conduit used was the Contegra type (57.6%) (n = 34), followed by the Labcor type (20.3%; n = 12). Postoperative fever occurred in 61% of patients (n = 36). Fourteen patients (38.8%) had a prolonged fever that lasted for more than seven days. Prolonged postoperative fever was significantly associated with the Labcor pulmonary conduit (P value < .001) and a longer duration of pacing wires (P value: .039). Significantly prolonged fever that lasted for more than 21 days occurred in five patients who all had inserted the Labcor pulmonary conduit. CONCLUSIONS: The Labcor pulmonary conduit type is a risk factor for prolonged postoperative fever. The protracted use of pacing wires could be a consequence of the prolonged fever rather than a cause. In the absence of a demonstrable infectious etiology for prolonged postoperative fever in cardiac patients with pulmonary conduit insertion, the Labcor pulmonary conduit could be the underlying cause. Alternative management of such cases may lead to decreased antibiotic use and morbidity.

Molecular epidemiology and genetic characterization of influenza B virus in Lebanon during 2016-2018.

BACKGROUND: Influenza B viruses are a major cause of serious acute respiratory infections in humans. METHODS: Nasopharyngeal swabs were collected from subjects with influenza-like illness during October 2016-June 2018 and screened for influenza A and B. The hemagglutinin (HA) and neuraminidase (NA) genes of the Lebanese influenza B specimens were sequenced and phylogenetically compared with the vaccine strains and specimens from the Eastern Mediterranean Region and Europe. RESULTS: Influenza A and B viruses co-circulated between October and May and peaked between January and March. During the 2016-2017 season, A/H3N2 (33.4%) and B/Yamagata (29.7%) were the predominantly circulating viruses followed by B/Victoria and A/H1N1pdm09 viruses. During the 2017-2018 season, A/H3N2 (31.5%) and A/H1Npdm09 (29.3%) were most prevalent with co-circulation of B/Yamagata and to a lesser extent B/Victoria viruses. The B/Yamagata specimens belonged to clade-3 while the B/Victoria belonged to clade-1A. None of the analyzed specimens had a mutation known to confer resistance to NA inhibitors (NAIs). CONCLUSION: Multiple subtypes of influenza co-circulate each year in Lebanon with a peak between January and March. The trivalent vaccine included a B/Victoria strain which mismatched the B/Yamagata lineage that predominated during the study period, highlighting the importance of quadrivalent vaccines.

Detection of ON1 and novel genotypes of human respiratory syncytial virus and emergence of palivizumab resistance in Lebanon.

Respiratory syncytial virus (RSV) is a common cause of respiratory tract infections in children and immunocompromised individuals. A multi-center surveillance of the epidemiologic and molecular characteristics of RSV circulating in Lebanon was performed. The attachment (G) and fusion (F) glycoproteins were analyzed and compared to those reported regionally and globally. 16% (83/519) of the nasopharyngeal swabs collected during the 2016/17 season tested positive for RSV; 50% (27/54) were RSV-A and 50% (27/54) were RSV-B. Phylogenetic analysis of the G glycoprotein revealed predominance of the RSVA ON1 genotype, in addition to two novel Lebanese genotype variants, hereby named LBA1 and LBA2, which descended from the ON1 and NA2 RSV-A genotypes, respectively. RSV-B strains belonged to BA9 genotype except for one BA10. Deduced amino acid sequences depicted several unique substitutions, alteration of glycosylation patterns and the emergence of palivizumab resistance among the Lebanese viruses. The emergence of ON1 and other novel genotypes that are resistant to palivizumab highlights the importance of monitoring RSV globally.

Prevalence and characteristics of acute respiratory virus infections in pediatric cancer patients.

BACKGROUND: Patients with pediatric cancer have a higher risk of morbidity and mortality because of respiratory viral infections than other patient populations. OBJECTIVES: To investigate the causative viruses of respiratory infections and their burden among patients with pediatric cancer in Lebanon. STUDY DESIGN: Nasopharyngeal swabs along with clinical and demographic data were collected from patients with pediatric cancer presenting febrile episodes with upper respiratory tract symptoms. Total nucleic acid was extracted from specimens followed by the real-time PCR analysis targeting 14 respiratory viruses to estimate the frequency of infections. RESULTS: We obtained 89 nasopharyngeal swabs from patients with pediatric cancer (mean age, 5.8 ± 4.2 years). Real-time PCR confirmed viral infection in 77 swabs (86.5%). Among these, 151 respiratory viruses were detected. Several viruses cocirculated within the same period; respiratory syncytial virus (RSV) being the most common (45.45%), followed by parainfluenza virus (PIV; 26%), influenza type B (26%), human metapneumovirus (24.6%), and human coronavirus (HCoV; 24.6%). Coinfections were detected in 55% of the subjects, and most of them involved RSV with one or more other viruses. A strong correlation was found between PIV, Flu (influenza of any type), RSV, and HCoV with the incidence of coinfections. RSV was associated with lower respiratory tract infections, nasal congestion, bronchitis, and bacteremia. HCoV was associated with bronchiolitis; rhinovirus was associated with hospital admission. CONCLUSION: Patients with pediatric cancer have a high burden of respiratory viral infections and a high incidence of coinfections. Molecular diagnostics can improve management of febrile episodes and reduce antibiotic use.

Challenges and opportunities for meningococcal vaccination in the developing world.

Meningococcal disease continues to be a life threatening infection with high morbidity and mortality even in appropriately treated patients. Meningococcal vaccination plays a major role in the control of the disease; however, implementing vaccination remains problematic in the developing world. The objective of this review is to identify the challenges facing the use of meningococcal vaccines in the developing world in order to discuss the opportunities and available solutions to improve immunization in these countries. Inadequate epidemiologic information necessary to implement vaccination and financial challenges predominate. Multiple measures are needed to achieve the successful implementation of meningococcal conjugate vaccination programs that protect against circulating serogroups in developing countries including enhanced surveillance systems, financial support and aid through grants, product development partnerships that are the end result of effective collaboration and communication between different interdependent stakeholders to develop affordable vaccines, and demonstration of the cost-effectiveness of new meningococcal vaccines.

Epidemiology and characteristics of urinary tract infections in children and adolescents.

BACKGROUND: Urinary tract infections (UTIs) are among the most common infections in the pediatric population. Over the last two decades, antibiotic resistance is increasing significantly as extended spectrum beta lactamase (ESBL) producing organisms are emerging. The aim of this study is to provide a comprehensive view of the epidemiologic characteristics of UTIs in hospitalized children, examine the risk factors of UTIs caused by ESBL-producing organisms, and determine the resistance patterns in the isolated organisms over the last 10 years. METHODS: Retrospective chart review was conducted at two Lebanese medical centers. Subjects were identified by looking at the following ICD-9 discharge codes: "Urinary tract infection," "UTI," "Cystitis," and/or "Pyelonephritis." Children less than 18 years of age admitted for UTI between January 1st, 2001 and December 31st, 2011 were included. Cases whose urine culture result did not meet our definition for UTI were excluded. Chi-square, Fisher's exact test, and multivariate logistic regression were used to determine risk factors for ESBL. Linear regression analysis was used to determine resistance patterns. RESULTS: The study included 675 cases with a median age of 16 months and female predominance of 77.7% (525 cases). Of the 584 cases caused by Escherichia coli or Klebsiella spp, 91 cases (15.5%) were found to be ESBL-producing organisms. Vesico-ureteral reflux and previous antibiotics use were found to be independent risk factors for ESBL-producing E. coli and Klebsiella spp. (p < 0.05). A significant linear increase in resistance to all generations of Cephalosporins (r (2) = 0.442) and Fluoroquinolones (r (2) = 0.698) was found. CONCLUSION: The recognition of risk factors for infection with ESBL-producing organisms and the observation of increasing overall resistance to antibiotics warrant further studies that might probably lead to new recommendations to guide management of UTIs and antibiotic use in children and adolescents.