Comparing single versus multiple virus detection in pediatric acute gastroenteritis postimplementation of routine multiplex RT-PCR diagnostic testing.

Utilizing multiplex real time polymerase chain reaction (RT-PCR) for rapid diagnosis of gastroenteritis, enables simultaneous detection of multiple pathogens. A comparative analysis of disease characteristics was conducted between cases with single and multiple viruses. Rotavirus vaccine was introduced in 2010, reaching a 70% coverage in 2 years. All rectal swabs collected from diarrheic children (<5 years) between December 2017 and March 2022 were included. Detection of the same viruses within 2 months was considered a single episode. Episodes with positive stool bacterial PCR were excluded. A total of 5879 samples were collected, revealing 86.9% (1509) with single virus detection and 13.1% (227) with multiple viruses. The most frequent combination was rotavirus and norovirus (27.8%), these infections followed a winter-spring seasonality akin to rotavirus. Children with multivirus infections exhibited higher immunodeficiency (OR 2.06) rates, but lower food allergy (OR 0.45) and prematurity rates (OR 0.55) compared to single infections. Greater disease severity, evaluated by the Vesikari score, was observed in multivirus episodes (p < 0.001, OR 1.12). Multivirus infections accounted for 13.1% of symptomatic cases in hospitalized young children. Despite vaccination efforts, rotavirus remained prominent, frequently in co-infections with norovirus. Overall, multivirus infections were linked to more severe diseases than single virus cases.

Implementing a multiplex-PCR test for the diagnosis of acute gastroenteritis in hospitalized children: Are all enteric viruses the same?

BACKGROUND: Multiplex-PCR is a valuable tool for diagnosing viral acute gastroenteritis (AGE), enabling the detection of multiple pathogens. However, distinguishing between active disease and shedding poses challenges. This study aimed to evaluate viral AGE epidemiology and compare clinical characteristics among the five most common viruses. METHODS: Rotavirus vaccine was introduced in 2010, with 70% coverage achieved in southern Israel in two years. All rectal swabs for multiplex-PCR targeting rotavirus, norovirus, adenovirus, astrovirus and sapovirus from hospitalized diarrheic children <5 years were included, from December 2017 through March 2022. Detection of the same virus within two months was considered a single episode. Clinical analysis included episodes with single-virus detection and negative bacterial PCR. RESULTS: Among 5,879 rectal swabs, 2,662 (45.3%) tested positive for at least one virus, with 245 (9.2%) showing multiple virus detection. Rotavirus was the most prevalent. While rotavirus exhibited typical winter-spring seasonality in 2018-19, an unusual off-season surge was observed during the second year of the COVID-19 pandemic. Among negative bacterial PCR episodes, 34.6% had mucus stool, 5.9% had bloody stool, and 29.3% received antibiotics. Astrovirus or sapovirus infections were associated with higher rates of hospital-acquired AGE and immunodeficiency (P<0.05), whereas rotavirus infections had higher rates of dehydration severity and acute kidney injury (P<0.05). DISCUSSION: Enteric viruses were detected in 45.3% of rectal swabs from hospitalized children with diarrhea. Despite vaccination efforts, rotavirus remained prevalent and caused more severe disease. Continuous surveillance using multiplex-PCR is crucial for accurate management and future prevention strategies for viral AGE.

Dynamics of Pediatric Antibiotic Use Differ between High- and Low-Prescribing Clinics after Pneumococcal Conjugate Vaccines.

OBJECTIVE: To compare dispensed oral antibiotic prescription rates (DAPRs) after implementation of pneumococcal conjugate vaccine (PCV) in high antibiotic-prescribing clinics (HPC) with low antibiotic-prescribing clinics (LPC) in 2 distinct ethnic groups of children (Jewish and Bedouin children) <5 years of age. METHODS: Clinics with ≥50 insured children, active both pre-PCV (2005-2009) and post-PCV (2010-2018) implementation, were included. HPC and LPC were defined by DAPRs above or below the median in each age and ethnic group. Monthly dispensed antibiotic prescription rate (DAPR) trends (adjusted for age and ethnicity) were calculated using interrupted time series. Mean yearly incidence rate-ratios (late PCV13 vs pre-PCV) were calculated. RESULTS: Bedouin HPC had the highest pre-PCV overall-DAPR per 1000 child-years ± SD (2520.4 ± 121.2), followed by Jewish HPC (1885.5 ± 47.6), Bedouin LPC (1314.8 ± 81.6), and Jewish LPC (996.0 ± 19.6). Shortly after PCV implementation, all DAPRs and amoxicillin/amoxicillin-clavulanate DAPRs declined in all groups except Jewish LPC, stabilizing within 4-5 years post-PCV. The rates and magnitudes of declines were directly proportional to the pre-PCV DAPR magnitudes, achieving near-complete closure of the pre-PCV DAPR gaps between the 4 groups (rates during late-PCV13 ranging from 1649.4 ± 23.5 [Bedouin HPC] to 1200.3 ± 72.4 [Jewish LPC]). CONCLUSIONS: PCVs are a powerful tool in reducing outpatient antibiotic consumption among young children, especially in HPC, resulting in partial closure of DAPR gap between HPC and LPC. The higher impact on HPC suggests that PCV-associated declines of respiratory disease may strongly contribute to a judicious antibiotic approach in clinics with high antibiotic consumption.

Effectiveness of BNT162b2 Vaccination During Pregnancy in Preventing Hospitalization for Severe Acute Respiratory Syndrome Coronavirus 2 in Infants.

OBJECTIVE: To assess the clinical effectiveness of the BNT162b2 vaccine during pregnancy in preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) hospitalizations of infants. STUDY DESIGN: A retrospective, multicenter, 1:3 case-control (test-negative) study. Symptomatic hospitalized infants less than 6 months of age, with a positive SARS-CoV-2 polymerase chain reaction test between January 3, 2021, and March 11, 2021, were matched by age and time to negative controls, hospitalized with symptoms compatible with SARS-CoV-2 infection. Mothers were defined as fully vaccinated who received 2 doses of BNT162b2 with the second given 2 weeks to 6 months before delivery; or partially vaccinated, if they received only 1 dose or 2 doses with the second given more than 6 months or less than 2 weeks before delivery. Severe SARS-CoV-2 was defined as a need for assisted ventilation. RESULTS: We matched 116 SARS-CoV-2 positive infants with 348 negative controls with symptoms compatible with SARS-CoV-2 infection. The effectiveness of fully vaccinated mothers was 61.6% (95% CI, 31.9-78.4) and the effectiveness of partially vaccinated mothers was not significant. Effectiveness was higher in infants 0-2 vs 3-6 months of age. The effectiveness (57.1%; 95% CI, 22.8-76.4) was similar when excluding mothers who were infected with SARS-CoV-2 during pregnancy. The OR of severe infection in infants born to unvaccinated vs fully vaccinated mothers was 5.8. CONCLUSIONS: At least 2 doses of BNT162b2 vaccine administered during the second or third trimester of pregnancy had an effectiveness of 61.6% in decreasing hospitalization for SARS-CoV-2 infection in infants less than 6 months of age.

Remote Versus In-person Outpatient Clinic Visits and Antibiotic Use Among Children During the COVID-19 Pandemic.

BACKGROUND: The proportion of remote clinic visits was expected to increase among children during the COVID-19 pandemic which might result in antibiotic overuse. METHODS: In southern Israel, 2 ethnic groups, Jewish and Bedouin, live side-by-side. Computerized data on visits for children <18 years were examined from clinics with ≥50 insured children, active both pre-COVID-19 and during the COVID-19 pandemic. Visits were divided into in-person and remote. Monthly infectious diagnoses and dispensed antibiotic prescription rates were calculated by age (<5, 5-17 years) and ethnic groups. Mean monthly rates of 2 parallel seasons (pre-COVID-19 and COVID-19 periods) were compared. RESULTS: Overall 2,120,253 outpatient clinic visits were recorded. Remote clinic visit rates (per 1000 children) increased from 97.04 and 33.86 in the pre-COVID-19 to 179.75 and 50.05 in the COVID-19 period in Jewish and Bedouin children, respectively ( P < 0.01) along with a reduction of in-person visit rates in both populations. Comparing pre-COVID-19 and COVID-19 periods, the rates of overall infectious diagnoses in remote visits increased. Nevertheless, dispensed antibiotic prescription rates in remote visits (per 1000 visits) remained unchanged (9.84 vs. 8.67, P = 0.70, in the Jewish population and 14.32 vs. 14.17, P = 1.00, in the Bedouin population in the pre-COVID-19 and COVID-19 periods, respectively) with a similar distribution of antibiotic categories. CONCLUSIONS: COVID-19 pandemic resulted in an expansion of remote visits of children <18 years with an increase in infectious diagnoses. However, remote dispensed antibiotic prescription rates remained unchanged. These dynamics were more accentuated in Jewish children, characterized by higher socio-economic conditions, compared to Bedouin children.

Disproportionate reduction in respiratory vs. non-respiratory outpatient clinic visits and antibiotic use in children during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic led to improved hygiene and reduced social encounters. Near elimination of the activity of respiratory syncytial virus and influenza viruses were observed, worldwide. Therefore, we assessed the rates of pediatric outpatient clinic visits and medications prescribed at those visits during the coronavirus disease 2019 (COVID-19) pandemic and pre-COVID-19 period (2016-2019). METHODS: Monthly and annual incidence rates for respiratory and non-respiratory diagnoses and dispensed prescription rates were calculated. Acute gastroenteritis (AGE) visits were analyzed separately since the mode of transmission is influenced by hygiene and social distancing. RESULTS: Overall, 5,588,702 visits were recorded. Respiratory and AGE visits declined by 49.9% and 47.3% comparing the COVID-19 and pre-COVID-19 periods. The respective rate reductions for urinary tract infections, trauma, and skin and soft tissue infections were 18.2%, 19.9%, and 21.8%. Epilepsy visits increased by 8.2%. Overall visits rates declined by 21.6%. Dispensed prescription rates of antibiotics and non-antibiotics respiratory medications declined by 49.3% and 44.4%, respectively. The respective declines for non-respiratory antibiotics and non-antibiotics were 15.1% and 0.2%. Clinic visits and prescription rates reductions were highest in April-May, following the first lockdown in Israel. CONCLUSIONS: COVID-19 pandemic resulted in a substantial reduction in respiratory outpatient clinic visits and dispensed respiratory drugs, with only a mild reduction seen for non-respiratory visits. These trends were probably driven by COVID-19 mitigation measures and by the profound disruption to non-SARS COV-2 respiratory virus activity.

COVID-19 Booster Vaccination Among Individuals With Schizophrenia in Israel.

Importance: Individuals with schizophrenia are at higher risk for severe COVID-19 illness and mortality. Previous reports have demonstrated vaccination gaps among this high-risk population; however, it is unclear whether these gaps have continued to manifest with the booster dose. Objective: To assess gaps in first, second, and booster vaccinations among individuals with schizophrenia. Design, Setting, and Participants: This was a matched, controlled, retrospective cohort study conducted in November 2021, and included follow-up data from March 2020, to November 2021. The study used the databases of Clalit Health Services, the largest health care management organization in Israel. Individuals with a diagnosis of schizophrenia at the onset of the pandemic and matched controls were included in the analysis. Main Outcomes and Measures: Rates of first, second, and booster vaccinations and time to reach vaccination. Results: The study included 34 797 individuals (mean [SD] age, 50.8 [16.4] years; 20 851 men [59.9%]) with schizophrenia and 34 797 matched controls (mean [SD] age, 50.7 [16.4] years; 20 851 men [59.9]) for a total of 69 594 individuals. A total of 6845 of 33 045 individuals (20.7%) with schizophrenia were completely unvaccinated, compared with 4986 of 34 366 (14.5%) in the control group (odds ratio [OR], 0.65; 95% CI, 0.62-0.67, P < .001). Once vaccinated, no significant differences were observed in the uptake of the second vaccine. Gaps emerged again with the booster vaccine, with 18 469 individuals (74.7%) with schizophrenia completing the booster, compared with 21 563 (77.9%) in the control group (OR, 0.83; 95% CI, 0.80-0.87, P < .001). Kaplan-Meier analyses indicated significant differences in time to reach vaccination, although gaps were lower compared with those reported in the first vaccination (log-rank test, 601.99 days; P < .001 for the first vaccination, compared with log-rank test, 81.48 days, P < .001 for the booster). Multivariate Cox regression analyses indicated that gaps in the first and booster vaccine were sustained even after controlling for demographic and clinical variables (first vaccine: hazard ratio [HR], 0.80; 95% CI, 0.78-0.81; P < .001 and booster: HR, 0.88; 95% CI, 0.87-0.90; P < .001) but were not significant for the second vaccine. Conclusions and Relevance: Results of this cohort study of Israeli adults found lower rates of COVID-19 vaccination among individuals with schizophrenia compared with a control group without schizophrenia, especially during the vaccine initiation phase. Countries worldwide should adopt strategies to mitigate the persistence of vaccination gaps to improve health care for this vulnerable population.

The impact of the pneumococcal conjugate vaccines on the incidence of community-acquired alveolar pneumonia in premature compared with in term-born infants.

BACKGROUND: Preterm-born children are prone to respiratory infections and complications during infancy and early childhood. In Israel, pneumococcal conjugated vaccines (PCVs) were introduced in 2009-2010, with high vaccination coverage. We assessed the impact of PCV implementation on community-acquired alveolar pneumonia (CAAP) in children < 2 years old born prematurely, in comparison with term born infants. METHODS: We conducted a prospective, active, population-based surveillance of children < 2 years old with radiologically-proven CAAP, visiting the only regional medical center. CAAP incidence in the pre-PCV and post-PCV eras were compared in early premature (29-32 weeks gestational age [WGA]), late premature (33-36 WGA) and term-born infants (>36 WGA). RESULTS: Of 214,947 births during the study period, 6'791 CAAP episodes were diagnosed; 211, 653 and 5,806 were in early premature, late premature and term infants, respectively. After PCV implementation, overall CAAP visits were reduced by 44% (95% CI 36-51): 60%, 21% and 45% among those born early preterm, late preterm and at term, respectively (statistically significant for children born early preterm and at term). For outpatients, the respective rate reductions were 79%, 40% and 65% (statistically significant for the children born at term). Importantly, the mean annual rates in the post-PCV period became similar in all 3 groups. The rate reductions among the hospitalized children were lower those that among the non-hospitalized children, with reductions of 56%, 16% and 33% for the three groups, respectively (statistically significant for early preterm and at term children). CONCLUSIONS: CAAP reduction trends after PCV implementation for preterm-born infants were similar to those for term-born infants. Whether this was because of similar direct PCV- protection, because of indirect (herd) protection or both, is unclear. Post-PCV implementation, the gaps in CAAP rates between infants born prematurely and at term were reduced.

Dynamics of Invasive Pneumococcal Disease in Israel in Children and Adults in the 13-Valent Pneumococcal Conjugate Vaccine (PCV13) Era: A Nationwide Prospective Surveillance.

BACKGROUND: Following 13-valent pneumococcal conjugate vaccine (PCV13) implementation in infants worldwide, overall and vaccine-type invasive pneumococcal disease (IPD) rates declined in children, with variable indirect impact on adults. METHODS: A population-based, prospective, nationwide active surveillance of IPD in Israel, 2004-2019 (for adults ≥18 years, 2009-2019). The 7-valent PCV (PCV7)/PCV13 were implemented in Israel in July 2009/November 2010, respectively, with >90% uptake in children <2 years. The 23-valent pneumococcal polysaccharide vaccine (PPV-23) uptake among those >65 years was ~75%. For pre-PCV episodes with missing serotype, extrapolations were applied. Overall, PCV13 serotypes (VT13) and non-VT13 (NVT) incidence rate ratios (IRRs) comparing pre-PCV (2004-2008), early-PCV (2009-2011), and late-PCV13 (2016-2019) periods were calculated for different age groups. RESULTS: Overall, 8614 IPD cases were recorded. IPD rates declined by 67% in children <5 and 5-17 years, comparing late-PCV13 versus pre-PCV periods (IRR [95% CI]: .33 [.27-.40] and .33 [.21-.50], respectively). For adults, comparing late-PCV13 with early-PCV periods, rates significantly declined by 53% in those aged 18-44, while rates did not decline significantly in other age groups. VT13 rates significantly declined in all ages, with decline rates ranging between 94% in children <5 years and 60% in adults ≥85 years. NVT rates significantly increased in <5-, 50-64-, and ≥65-year age groups. In the late-PCV13 period, serotypes 3, 14, and 19A remained the predominant VT13, while serotypes 8 and 12F emerged as predominant NVTs. CONCLUSIONS: Continuous monitoring of circulating serotypes in all ages demonstrated direct and indirect PCV effects, which are essential for the development of new vaccination strategies.

Decline in Pneumococcal Disease in Young Children During the Coronavirus Disease 2019 (COVID-19) Pandemic in Israel Associated With Suppression of Seasonal Respiratory Viruses, Despite Persistent Pneumococcal Carriage: A Prospective Cohort Study.

BACKGROUND: The incidence of invasive pneumococcal disease (IPD) declined during the COVID-19 pandemic. Previous studies hypothesized that this was due to reduced pneumococcal transmission resulting from nonpharmaceutical interventions. We used multiple ongoing cohort surveillance projects in children <5 years to test this hypothesis. METHODS: The first SARS-CoV-2 cases were detected in February 2020, resulting in a full lockdown, followed by several partial restrictions. Data from ongoing surveillance projects captured the incidence dynamics of community-acquired alveolar pneumonia (CAAP), nonalveolar lower respiratory infections necessitating chest X-rays (NA-LRIs), nasopharyngeal pneumococcal carriage in nonrespiratory visits, nasopharyngeal respiratory virus detection (by polymerase chain reaction), and nationwide IPD. Monthly rates (January 2020 through February 2021 vs mean monthly rates 2016-2019 [expected rates]) adjusted for age and ethnicity were compared. RESULTS: CAAP and bacteremic pneumococcal pneumonia were strongly reduced (incidence rate ratios [IRRs]: .07 and .19, respectively); NA-LRIs and nonpneumonia IPD were also reduced by a lesser magnitude (IRRs: .46 and .42, respectively). In contrast, pneumococcal carriage prevalence was only slightly reduced, and density of colonization and pneumococcal serotype distributions were similar to previous years. The decline in pneumococcus-associated disease was temporally associated with a full suppression of respiratory syncytial virus, influenza viruses, and human metapneumovirus, often implicated as co-pathogens with pneumococcus. In contrast, adenovirus, rhinovirus, and parainfluenza activities were within or above expected levels. CONCLUSIONS: Reductions in pneumococcal and pneumococcus-associated diseases occurring during the COVID-19 pandemic in Israel were not predominantly related to reduced pneumococcal carriage and density but were strongly associated with the disappearance of specific respiratory viruses.

Decline in pneumococcal nasopharyngeal carriage in children 6-23 months with respiratory illnesses following pneumococcal conjugate vaccine implementation.

BACKGROUND: Following pneumococcal conjugate vaccines (PCVs) implementation, worldwide, pneumococcal carriage rates remained stable, indicating full replacement of vaccine-serotypes (VT) with non-VT. However, data are scarce regarding PCV impact on pneumococcal carriage rates in healthy vs. sick children. We assessed pneumococcal carriage rates dynamics in healthy and sick children 6-23 months, following PCV introduction. METHODS: This is a prospective, population-based surveillance conducted during the years 2009-2017, in southern Israel. Three groups were defined as follows: Children without respiratory infection signs (the healthy/non-respiratory group); Children who had a chest radiography at the hospital (the Hosp-CXR group); and children with community-acquired alveolar pneumonia (CAAP). Rate ratios (RRs; 95% CI) were calculated, comparing between late-13-valent PCV (PCV13) period (2016-2017) and early-PCV period (2009-2010). Rate ratios were adjusted for antibiotic administration, seasonality and ethnicity, and separate calculations were performed for 6-11 and 12-23 month old children. RESULTS: Overall, 51% of 8627 nasopharyngeal cultures were positive. In 2009-2010 (early-PCV period), the overall carriage rate was 55%; serotypes included in the PCV13 carriage rates were 28%, 31% and 38% in the healthy/non-respiratory, Hosp-CXR, and CAAP groups, respectively. Overall carriage rates in healthy/non-respiratory episodes were stable (~54%) when comparing between 2016 and 17 and 2009-10 (RR = 0.98; 0.84-1.15). In contrast, rates significantly declined for Hosp-CXR (RR = 0.78; 0.63-0.98) and CAAP (RR = 0.65; 0.47-0.89). These trends were driven by ~ 80% VT reductions, coupled with non-VT increase. CONCLUSIONS: Following 7-valent PCV/ PCV13 introduction, pneumococcal carriage rates declined in respiratory diseases, but not in healthy children and children without respiratory infections. These trends suggest that a reduction in pneumococcal carriage rates during respiratory infections indicates a decline in respiratory infections caused by VT, while carriage rates in non-respiratory cases reflect non-VT predominance, that have low disease potential for respiratory disease.

COVID-19 in a Subset of Hospitalized Children in Israel.

BACKGROUND: Most pediatric coronavirus disease 2019 (COVID-19) is mild. We assessed nationally severe COVID-19, including pediatric inflammatory multisystem syndrome (PIMS), in hospitalized children. METHODS: An ongoing, prospective, national surveillance was conducted from March 2020 through March 2021, at 20 hospitals treating children <18 years across Israel (~75% of Israeli hospitals). RESULTS: Overall, 1007 cases (439 outpatients and 568 hospitalized) identified represent 0.35% of pediatric COVID-19 nationwide (n = 291 628). Of hospitalized cases, 464 (82%), 48 (8%), and 56 (10%) had mild, moderate/severe, and PIMS disease, respectively. The mean ± SD age was 5.6 ± 6.4 years. In mild, moderate/severe, and PIMS disease, 55%, 23%, and 4% of patients were <1 year old, respectively. Obesity was reported in 1%, 4%, and 13% of patients, respectively (P < .001). The most common symptom was fever in 67%, 60%, and 100%, respectively, whereas respiratory symptoms were documented in 33%, 41%, and 38% of patients, respectively. Lymphopenia was recorded in 25%, 60%, and 86% of cases, respectively. PIMS diagnosis was mainly serology-based (in 59%). Gastrointestinal symptoms, cardiovascular involvement, rash, and conjunctivitis were noted in 82%, 61%, 57%, and 34% of PIMS episodes, respectively. Elevated C-reactive protein (100%), ferritin, troponin, D-dimer, low albumin, and thrombocytopenia were common in PIMS. Echocardiography revealed pathological findings in 33% of patients. PIMS mainstay treatment included corticosteroids (77%) and intravenous immunoglobulin (53%). No mortality was recorded. CONCLUSIONS: At a national level, pediatric COVID-19 is mild, even in hospitalized cases, with only a third presenting with respiratory involvement. PIMS is rare, but necessitates a high index of suspicion, and with suitable treatment prognosis is favorable.

Unraveling the Impact of Pneumococcal Conjugate Vaccines on Ambulatory Antibiotic Drug Consumption in Young Children: An Interrupted Time-Series Analysis.

BACKGROUND: Pneumococcal conjugate vaccines (PCVs) reduce respiratory infections in young children, the main antibiotic consumers. Following PCV implementation, dispensed antibiotic prescription (DAP) rates in young children were expected to decline. METHODS: Computerized data on DAP for children <5 years were examined during a 13-year period (including 4 pre-PCV years). All DAPs from clinics with ≥50 insured children, active both pre- and post-PCV implementation were included. Interrupted time-series with segmented regression was applied to analyze monthly DAP rate trends, adjusted for age, ethnicity, and season. Incidence rate ratios (IRRs) of DAPs during the late PCV13 period versus 4 years pre-PCV were calculated both as absolute rate ratios (aIRRs) and relative to expected rates (rIRRs). RESULTS: Of 1 090 870 DAPs, 57% were in children <2 years. All-DAP rates peaked in the cold season. Post-PCV7/PCV13 implementation, all DAP rates abruptly and significantly declined, reaching a plateau within 5 years. This was largely driven by amoxicillin/amoxicillin-clavulanate (75% of DAPs). Age <2 years and Bedouin ethnicity were significantly associated with higher pre-PCV DAP rates but with faster and greater decline post-PCV, achieving near elimination of gaps between ages and ethnic groups. Overall reduction (95% CIs) in DAP rates per 1000 was estimated between aIRR (344.7 [370.9-358.4]) and rIRR (110.4 [96.9-123.7]) values. CONCLUSIONS: Shortly following PCV implementation, overall DAP rates showed an abrupt, steep decline, stabilizing within 5 years, in parallel to post-PCV respiratory infection trends previously described in this population, suggesting causality. The variable patterns of certain drug categories suggest additional influences beyond PCV.

Effectiveness of the 7- and 13-Valent Pneumococcal Conjugate Vaccines Against Vaccine-Serotype Otitis Media.

BACKGROUND: Despite the demonstrated impact of pneumococcal vaccine (PCV) implementation on otitis media (OM), demonstration of real-life serotype-specific effectiveness of the 7-valent and 13-valent PCVs (PCV7 and PCV13) is lacking owing to the paucity of culture-positive cases. Furthermore, prelicensure PCV13 efficacy against OM was not studied. METHODS: The study was conducted from October 2009 to July 2013. Case patients were children aged 5-35 months with OM (mostly complex OM [recurrent/nonresponsive, spontaneously draining, chronic with effusion]) from whom middle-ear fluid culture was obtained; controls were contemporary children with rotavirus-negative gastroenteritis in a prospective population-based rotavirus surveillance, from the same age group with similar ethnic distribution and geographic location. Vaccine effectiveness (VE) was estimated as 1 minus the odds ratio using unconditional logistic regression, adjusting for time since PCV implementation, age, and ethnicity. RESULTS: A total of 223 case patients and 1370 controls were studied. Serotypes 19F and 19A together caused 56.1% of all vaccine-type (VT) OM. VE of ≥2 PCV doses in children aged 5-35 months was demonstrated as follows: PCV7 against OM due to PCV7 serotypes, 57.2% (95% confidence interval, 6.0%-80.5%); PCV13 against OM due to PCV13 serotypes, 77.4% (53.3%-92.1%); PCV13 against OM due to the 6 additional non-PCV7 serotypes 67.4% (17.6%-87.1%); PCV13 against OM due to serotype 19F, 91.3% (1.4%-99.2%); and PCV13 against OM due to serotype 3, 85.2% (23.9%-98.4%). PCV7 and PCV13 VE against OM due to serotype 19A in children aged 12-35 months was 72.4% (95% confidence interval, 6.2%-91.9%) and 94.6% (33.9%-99.6%), respectively. CONCLUSIONS: PCV7 and PCV13 were effective against complex OM caused by the targeted serotypes.

Post-13-Valent Pneumococcal Conjugate Vaccine Dynamics in Young Children of Serotypes Included in Candidate Extended-Spectrum Conjugate Vaccines.

After worldwide implementation of 10-valent and 13-valent pneumococcal conjugate vaccines (PCV10/PCV13), a 20-valent PCV (PCV20) was developed. We assessed dynamics of non-PCV13 additional PCV20 serotypes (VT20-13), compared with all other non-VT20 serotypes, in children <2 years of age in late PCV13 (2015-2017) and early PCV (2009-2011) periods. Our prospective population-based multifaceted surveillance included isolates from carriage in healthy children, children requiring chest radiography for lower respiratory tract infections (LRTIs), and children with non-LRTI illness, as well as isolates from acute conjunctivitis, otitis media (OM), and invasive pneumococcal disease (IPD). After PCV13 implementation, VT20-13 increased disproportionally in OM, IPD, and carriage in LRTI. VT20-13/non-VT20 prevalence ratio range was 0.26-1.40. VT20-13 serotypes were more frequently antimicrobial-nonsusceptible than non-VT20 serotypes. The disproportionate increase of VT20-13 in respiratory infections and IPD points to their higher disease potential compared with all other non-VT20 as a group.

Effectiveness of Pneumococcal Conjugate Vaccines Against Community-acquired Alveolar Pneumonia Attributable to Vaccine-serotype Streptococcus pneumoniae Among Children.

INTRODUCTION: Streptococcus pneumoniae is a leading cause of pneumonia among children. However, owing to diagnostic limitations, the protection conferred by pneumococcal conjugate vaccines (PCVs) against pediatric pneumonia attributable to vaccine-serotype pneumococci remains unknown. METHODS: We analyzed data on vaccination and nasopharyngeal pneumococcal detection among children <5 years old with community-acquired alveolar pneumonia (CAAP; "cases") and those without respiratory symptoms ("controls"), who were enrolled in population-based prospective surveillance studies in southern Israel between 2009 and 2018. We measured PCV-conferred protection against carriage of vaccine-serotype pneumococci via the relative risk of detecting these serotypes among vaccinated versus unvaccinated controls. We measured protection against progression of vaccine serotypes from carriage to CAAP via the relative association of vaccine-serotype detection in the nasopharynx with CAAP case status, among vaccinated and unvaccinated children. We measured PCV-conferred protection against CAAP attributable to vaccine-serotype pneumococci via the joint reduction in risks of carriage and disease progression. RESULTS: Our analyses included 1032 CAAP cases and 7743 controls. At ages 12-35 months, a PCV13 schedule containing 2 primary doses and 1 booster dose provided 87.2% (95% confidence interval: 8.1-100.0%) protection against CAAP attributable to PCV13-serotype pneumococci, and 92.3% (-0.9%, 100.0%) protection against CAAP attributable to PCV7-serotype pneumococci. Protection against PCV13-serotype and PCV7-serotype CAAP was 67.0% (-424.3%, 100.0%) and 67.7% (-1962.9%, 100.0%), respectively, at ages 36-59 months. At ages 4-11 months, 2 PCV13 doses provided 98.9% (-309.8%, 100.0%) and 91.4% (-191.4%, 100.0%) against PCV13-serotype and PCV7-serotype CAAP. CONCLUSIONS: Among children, PCV-conferred protection against CAAP attributable to vaccine-targeted pneumococcal serotypes resembles protection against vaccine-serotype invasive pneumococcal disease.

A Prospective, Population-based Study to Determine the Incidence and Bacteriology of Bacterial Conjunctivitis in Children <2 Years of Age Following 7-Valent and 13-Valent Pneumococcal Conjugate Vaccine Sequential Implementation.

BACKGROUND: Bacterial conjunctivitis is most commonly caused by nontypeable Haemophilus influenzae (NTHi), followed by Streptococcus pneumoniae. No population-based data on the impact of pneumococcal conjugate vaccines (PCVs) on the incidence of bacterial conjunctivitis have been published. We assessed rate dynamics of overall, pneumococcal, and NTHi conjunctivitis in children aged 2-23 months in southern Israel before and after PCV implementation. METHODS: This is a 12-year prospective, population-based surveillance, from July 2004 through June 2017. Our medical center serves a captive population of approximately 30 000 children < 2 years of age, and its clinical microbiology laboratory processes > 80% of all community-derived cultures, enabling incidence calculation. The 7-valent and 13-valent PCVs (PCV7 and PCV13, respectively) were implemented in the national immunization program in July 2009 and November 2010, respectively. Pneumococci, NTHi, Moraxella catarrhalis, and Streptococcus pyogenes were considered pathogens. Continuous annual incidences and incidence rate ratios comparing the PCV13 period (2015-2017) to the pre-PCV period (2004-2008) were calculated. RESULTS: Disease caused by PCV13 serotypes declined by 93%, without significant replacement with non-PCV13 serotypes. Rates of pneumococcal, NTHi, and overall culture-positive episodes declined by 59%, 41%, and 42%, respectively, while rates of culture-negative and other pathogens episodes did not change significantly. An overall reduction in all submitted culture rates of 35% was observed. This pattern was seen across all ages, including infants aged 2-5 months. CONCLUSIONS: PCV7/PCV13 implementation resulted in a marked and significant decline in pneumococcal, NTHi, and overall conjunctivitis rates in children < 2 years of age. The impact on NTHi episodes alludes to the role of pneumococcus-NTHi interaction in conjunctivitis. The impact in infants aged < 6 months suggests herd protection.

Serotype Patterns of Pneumococcal Disease in Adults Are Correlated With Carriage Patterns in Older Children.

BACKGROUND: The importance of specific serotypes causing invasive pneumococcal disease (IPD) differs by age. Data on pneumococcal carriage in different age groups, along with data on serotype-specific invasiveness, could help explain these age-related patterns and their implications for vaccination. METHODS: Using pneumococcal carriage and disease data from Israel, we evaluated the association between serotype-specific IPD in adults and serotype-specific carriage prevalence among children in different age categories, while adjusting for serotype-specific invasiveness. We estimated carriage prevalence using different age groupings that were selected a priori. The Deviance Information Criterion was used to determine which age groupings of carriage data best fit the adult IPD data. Serotype-specific disease patterns were further evaluated by stratifying IPD data by comorbidity status. RESULTS: The relative frequency of serotypes causing IPD differed between adults and children, and also differed between older and younger adults and between adults with and without comorbidities. Serotypes overrepresented as causes of IPD in adults were more commonly carried in older children compared with younger children. In line with this, the serotype-specific frequency of carriage in older children, rather than infants, best correlated with serotype-specific IPD in adults. CONCLUSIONS: These analyses demonstrate that the serotype patterns in carriage in older children, rather than infants, are best correlated with disease patterns in adults. This might suggest these older children are more influential for disease patterns in adults. These insights could help in optimizing vaccination strategies to reduce disease burden across all ages.