Impact of Nirsevimab on Pediatric RSV-Related Lower Respiratory Tract Infections: A Retrospective Pre–Post Observational Study in Tuscany, Italy Francesco Nieddu, Marta Verzieri, Marina Vignoli, Valeria Astorino, Silvia Boscia, Laura Pisano, Silvia Ricci, Lorenzo Lodi, Valentina Guarnieri, Francesca Di Berardino, Francesca Figlioli, Stefano Masi, Giuseppe Indolfi, Chiara Azzari, Maria Moriondo Infectious Diseases and Therapy, 2026 Respiratory syncytial virus (RSV) is the leading cause of respiratory infections and hospitalization among infants and a major burden on pediatric emergency department (EDs). Nirsevimab has recently been introduced for universal use in all infants entering their first RSV season. However, real-world data on its public health impact are still limited, particularly regarding attendances at pediatric ED. We conducted a retrospective, observational, pre–post intervention study at the Meyer Children’s Hospital (Tuscany, Italy). The 2024–25 RSV season, when nirsevimab was firstly implemented, was compared with the three preceding seasons. ED attendances, hospitalization, and pediatric intensive care unit (PICU) admissions for lower respiratory tract infections (LRTIs) of any etiology were analyzed. During the 2024–25 season, overall ED attendances for LRTIs, regardless of etiology, decreased by 67.3%. Hospital admissions for LRTIs dropped by 64.7%, and PICU admissions by 86.2%. RSV-confirmed LRTIs declined by 96.5%. Universal nirsevimab prophylaxis markedly reduced the burden of respiratory infections in eligible infants, leading to a significant reduction in the use of healthcare resources, including ED visits, hospitalization, and PICU admissions. Respiratory syncytial virus is a common virus that infects the lungs and airways. It is the main cause of serious breathing problems and hospital admissions in babies. These infections also create a heavy workload for pediatric emergency departments. Respiratory syncytial virus infection season may commonly run from October to April. Nirsevimab is a long-acting preventive antibody that helps protect babies from severe respiratory syncytial virus disease. In Italy, healthcare services started giving nirsevimab to babies entering their first respiratory syncytial virus season during the 2024–25 season. We studied the real-world impact of this prevention strategy at Meyer Children’s Hospital in Tuscany, Italy. We compared the 2024–25 respiratory syncytial virus season with the three previous seasons. We analyzed visits to the pediatric emergency department, hospital admissions, and intensive care admissions for lower respiratory tract infections, both when respiratory syncytial virus was confirmed and when the cause of infection was not confirmed. After the introduction of nirsevimab, visits to the emergency department for lower respiratory tract infections dropped by more than two-thirds. Hospital admissions for these infections fell sharply, and intensive care admissions decreased by more than 80%. Confirmed respiratory syncytial virus lower respiratory tract infections almost disappeared. These findings show that protecting eligible babies with nirsevimab greatly reduced serious respiratory infections and eased pressure on hospitals and emergency departments.
Pediatric Intracranial Abscesses in a Tertiary Care Center: Antimicrobial Management, Diagnostic Yield of Molecular Testing and Radiologic Follow-Up Roberto Privato, Federica Attaianese, Carlotta Montagnani, Agnese Tamborino, Elena Chiappini, Francesco Nieddu, Maria Moriondo, Angelo Galano, Flavio Giordano, Federico Mussa, Giuseppe Indolfi, Sandra Trapani, Luisa Galli, Elisabetta Venturini Pediatric Infectious Disease Journal, 2026 Background: Brain abscesses and intracranial empyemas are rare but serious infections associated with substantial morbidity and long-term neurologic sequelae. Microbiologic confirmation is often limited by prior empirical therapy, and the diagnostic yield of real-time polymerase chain reaction in real-world settings remains uncertain. Evidence guiding antimicrobial duration, microbiologic work-up and radiologic follow-up in children is limited. We aimed to describe a pediatric cohort, focusing on management strategies, molecular diagnostics and radiologic follow-up. Methods: In this single-center study, we reviewed the clinical charts of a tertiary care pediatric hospital in Italy from 2017 to 2025. Children younger than 18 years diagnosed with brain abscess or subdural/epidural empyema were included. Clinical, radiologic, microbiologic, and immunologic treatment and outcome data were collected. Comparisons were performed using the Mann–Whitney U test and Fisher exact test. Results: The study cohort included 26 children (17 brain abscesses, 7 subdural empyemas and 2 epidural empyemas). Pathogens were identified in 21 patients (81%), with 23 isolates. Real-time polymerase chain reaction exclusively detected 43% of isolates (10/23). Half of patients received <6 weeks of intravenous therapy without recurrence, including 35% of brain abscesses. Children undergoing drainage/craniotomy had larger lesions ( P = 0.04) and required longer intravenous treatments than those managed conservatively (42 vs. 20 days, P = 0.022). Radiologic follow-up showed residual findings in most cases (60%). One child died; neurologic sequelae occurred in 15% of cases. Conclusions: Pediatric intracranial abscesses require intensive multidisciplinary care, with marked heterogeneity in current treatment strategies. Molecular testing substantially enhances diagnostic yield and pathogen identification. Radiologic structural sequelae are common, but their prognostic significance remains unclear. Standardized pediatric protocols and well-designed prospective studies are needed to optimize antimicrobial stewardship, define which candidates may safely receive shorter intravenous courses, and harmonize follow-up imaging.
Blood And Pharyngeal Swab Polymerase Chain Reaction Testing: Diagnostic and Therapeutic Implications in Children With Acute Nonbacterial Encephalitis Roberto Privato, Sandra Trapani, Elisabetta Venturini, Maria Moriondo, Francesco Nieddu, Chiara Azzari, Luisa Galli, Giuseppe Indolfi Pediatric Infectious Disease Journal, 2025 Background: Children with acute nonbacterial encephalitis are often treated with extended antimicrobial therapies. Negative results from cerebrospinal fluid (CSF) examinations frequently lead to unnecessary prolongation of empirical treatments due to uncertain etiology. To enhance the identification rate of infectious causative agents, additional tests are increasingly performed on non-CSF specimens, including viral polymerase chain reaction (PCR) testing on blood or pharyngeal swabs. This study aimed to evaluate the impact of blood and pharyngeal swab PCR testing on the duration of empirical intravenous (IV) therapy in children with acute nonbacterial encephalitis, as well as its usefulness in identifying viral etiologies. Methods: A single-center, retrospective observational study was conducted on children aged 28 days to 18 years hospitalized with acute, nonbacterial encephalitis from January 2019 to August 2024. Data on age, sex, clinical presentation, laboratory features, instrumental investigations, administered therapy, results of PCR testing on different specimens and identified etiology were collected. Results: Among 52 encephalitis cases, viruses were detected via PCR in CSF in 9 cases (17%), pharyngeal swabs in 8 (15%) and blood in 5 (10%). Herpetic infections were more frequently found on CSF (P < 0.001), while nonherpetic viruses were detected in non-CSF specimens in most cases. The duration of IV antibiotics was shorter in patients with positive viral PCR results from blood or pharyngeal swabs (P = 0.009). Prolonged antibiotic therapy despite negative bacterial CSF tests was inversely associated with positive PCR in blood/pharyngeal swabs [adjusted odds ratio (aOR), 0.14; P = 0.031) and directly associated with sepsis-like presentation (aOR, 5.08; P = 0.028). No difference in IV acyclovir duration was found between those with nonherpetic viral infections and those with unidentified etiology (P = 0.12). Conclusions: Performing viral PCR on both CSF and non-CSF specimens is associated with a higher detection rate of viral etiology and may positively impact the duration of empirical antimicrobial therapy in children with nonbacterial encephalitis.
Public health impact of nirsevimab and reduction of RSV hospitalisation in all infants: early real-world data from Tuscany (Italy) in the 2024–25 RSV season Francesco Nieddu, Marina Vignoli, Emanuela Ferraro, Silvia Boscia, Valeria Astorino, Caterina Pelosi, Valentina Guarnieri, Francesca Quaranta, Vanessa Perone, Paolo Biasci, Lorenzo Lodi, Silvia Ricci, Carlo Dani, Giuseppe Indolfi, Pierre Bourron, Salvatore Parisi, Chiara Azzari, Maria Moriondo European Journal of Pediatrics, 2025 Real-world evidence on the public health impact of nirsevimab across a full RSV season in Italy is currently lacking, particularly with respect to hospitalisations and admissions to paediatric intensive care units (PICU), and only limited data are available worldwide. This study aimed to evaluate, in a real-world setting, the public health impact of nirsevimab on RSV-related hospitalisations and PICU admissions in Tuscany. This observational retrospective study included all children under one year of age experiencing their first RSV season, i.e., those born between April and March of the 2021–22, 2022–23, 2023–24, and 2024–25 seasons, who were hospitalised at the Meyer Children’s Hospital, a tertiary regional paediatric hospital in Tuscany, for respiratory symptoms with RSV confirmed via real-time PCR testing. Starting November 1st 2024, Nirsevimab was offered to all infants born between 1 April, 2024, and 31 March, 2025. The percentage reduction in RSV-related hospitalisations was calculated by comparing the number of hospitalisations observed in 2024/25 with the mean number recorded across the three preceding RSV seasons. Immunization coverage reached around 90%. During the 2024–2025 RSV season, RSV-related. hospitalisations decreased by 82.1% among infants eligible for immunization, by 83.2% among those born during the RSV season, and by 81.5% among those born before the season. PICU admissions decreased by 85.2%, 84.0%, and 86.8%, respectively, in the same groups. High coverage of nirsevimab immunization substantially reduced RSV-related hospitalisations among infants in Tuscany during the 2024–2025 season. The consistent benefits observed across both in-season and out-of-season birth cohorts support a universal immunization program for all infants, including those born from April onward, in Italy. What is Known: • RSV is the leading cause of infant hospitalisations for lower respiratory tract infections, especially in those ≤12 months. Real-world data on season-wide nirsevimab public health impact in Italy were lacking.. What is New: • Universal nirsevimab immunisation in Tuscany led to an 82.1% reduction in RSV-related hospitalisations and 85.2% in PICU admissions in infants eligible for immunization. Findings support universal over selective immunisation to protect all infants entering their first RSV season.
Bordetella pertussis in hospitalised children and adolescents: the impact of vaccination delay, Tuscany, Italy, 2016 to 2024 Francesco Nieddu, Francesca Quaranta, Marina Vignoli, Matilde Peri, Valentina Guarnieri, Caterina Pelosi, Emanuela Ferraro, Lorenzo Lodi, Silvia Ricci, Giuseppe Indolfi, Chiara Azzari, Maria Moriondo Eurosurveillance, 2025 BACKGROUND Pertussis is a highly contagious respiratory infection caused by Bordetella pertussis. Vaccination against pertussis is included in the Italian vaccination programme with three doses administered at 3, 5 and 11 months, booster doses at 6 and 12–18 years, and every 10 years. Vaccination coverage in Tuscany is high among infants (97.7% vs 94.7% national average at 24 months) and adolescents (75.8% vs 68.4% national average at 16 years). AIM We aimed to investigate case numbers, vaccination status and time points for vaccination of children and adolescents hospitalised for pertussis. METHODS We collected data on children and adolescents aged ≤ 16 years and hospitalised for laboratory-confirmed pertussis in 2016–2024 at a tertiary hospital in Tuscany. RESULTS A total of 384 children and adolescents were hospitalised in 2016–2024. Annual case numbers increased from an average of 28.2 cases in 2016–2019 to 259 cases in 2024, with 136 (52.5%) cases in adolescents. Of the 107 cases aged 12–16 years, 93 (86.9%) were unvaccinated or had not received the second booster. A considerable time gap between the earliest eligible day for vaccination and hospitalisation was observed. In infants, a median of 31 days (interquartile range (IQR): 10–131 days) was noticed for the first dose, 44 days (IQR: 22–70 days) for the second and 53 days for the third. In 12–16-year-olds, a median of 395 days (IQR: 236–717) was seen for the second booster. CONCLUSION Administering adolescent booster doses earlier, vaccinating at the earliest eligible time points, and promoting timely vaccination through targeted communication campaigns may reduce pertussis-related hospitalisations.
Recent trends in hospitalizations for respiratory syncytial virus after the COVID-19 pandemic and before routine immunization: Seasonality and severity updates from the 2023/2024 season in Tuscany, Italy Vieri Lastrucci, Martina Pacifici, Monia Puglia, Giorgia Alderotti, Elettra Berti, Guglielmo Bonaccorsi, Maria Moriondo, Massimo Resti, Diego Peroni, Marco Martini, Francesco Nieddu, Marina Vignoli, Chiara Azzari, Rosa Gini, Marco Del Riccio, Fabio Voller International Journal of Infectious Diseases, 2025 OBJECTIVES: Respiratory syncytial virus (RSV) epidemiology was disrupted by the COVID-19 pandemic. This study investigates the 2023/2024 RSV season in Tuscany, Italy, to assess trends in seasonality and incidence of RSV-associated hospitalizations compared with pre-pandemic and prior post-pandemic seasons. METHODS: We analyzed RSV-associated hospitalizations in Tuscany during the 2023/2024 season, just before the implementation of routine immunization with nirsevimab, with a dynamic cohort consisting of all resident children aged ≤2 years, using regional registries. Seasonality was assessed using the 60% mean detection threshold method, and incidence rate ratios and risk ratios were used to compare hospitalization incidence and risk of severe hospitalization (intensive care unit, continuous positive airway pressure, or mechanical ventilation) with pre-pandemic seasons, 2017/2018 and 2018/2019, respectively. RESULTS: Among 64,963 children aged <2 years, 724 were hospitalized for RSV. The epidemic began in week 42 of 2023, peaked in week 52, and ended in week 12 of 2024 (18 weeks total). Incidence remained significantly higher than pre-pandemic levels (incidence rate ratio 3.0, 95% confidence interval 2.7-3.4), whereas severity risk was comparable to pre-pandemic seasons. CONCLUSIONS: Seasonality in 2023/2024 aligned more closely with pre-pandemic patterns, but incidence remained elevated, likely due to immunity debt at the population level. Monitoring RSV epidemiology is essential as new preventive measures, such as nirsevimab and vaccines, are introduced.
Childhood invasive pneumococcal disease and acute otitis media in Central Greece during 2005-2024 – A report at the doorstep of the new multivalent PCV era George A. Syrogiannopoulos, Aspasia N. Michoula, Maria Moriondo, Francesco Nieddu, Theoni G. Syrogiannopoulou, Michael B. Anthracopoulos, Efthymia Petinaki, Chiara Azzari, Ioanna N. Grivea Vaccine, 2025 BACKGROUND: In Greece, pneumococcal conjugate vaccines (PCVs) became sequentially available: 7-valent in October 2004, 10-valent in May 2009, 13-valent in June 2010 and 15-valent in March 2023; soon after availability all vaccines were incorporated in the National Ιmmunization Program except for PCV7 which was implemented in January 2006. Since July 2010, PCV13 has been the most commonly used PCV. Surveillance at a regional and a national level is a valuable tool to monitor the impact of PCVs. METHODS: At the University General Hospital of Larissa (single academic tertiary care referral center for Central Greece) we prospectively obtained samples from 0 to 15-year-old children consequently diagnosed with invasive pneumococcal disease (IPD) or acute otitis media (AOM) with spontaneous perforation of the tympanic membrane (SPTM) during three time periods: the PCV7 (2005-2010), the early-mid PCV13 (2011-2016) and the late PCV13 (2017-2024) periods. Pneumococci were serotyped by capsular swelling. PCR was applied on pleural fluid and CSF specimens. RESULTS: A total of 106 (61 IPD and 45 AOM with SPTM) serotype-evaluable samples were obtained. Serotypes 19A and 19F peaked in 2005-2010 and decreased thereafter. Increased number of IPD cases due to serotype 3 were noted in the 2011-2016 and 2017-2024 periods. The emergence of non-PCV13 serotypes in IPD and AOM with SPTM was noted in the late PCV13 period. In 2017-2024 the most common serotypes responsible for IPD were 3 and 12F. The projected additional protection from IPD, beyond that of PCV13, offered by PCV15 and PCV20 during 2017-2024 was 10 % and 30 %, respectively. The respective additional protection from AOM offered by the two vaccines was 0 % and 21.4 %. CONCLUSION: Our findings in Central Greece suggest that PCVs of increasing valency are expected to provide substantial additional coverage for pneumococcal disease as compared to PCV13.
Exploring Risk Factors Associated With Intensive Care Unit Admission in a Retrospective Cohort of 631 Children With Bronchiolitis Valentina Guarnieri, Giordano Palmas, Sandra Trapani, Antonella Mollo, Chiara Macucci, Irene Gambini, Valentina Mottola, Chiara Rubino, Maria Moriondo, Francesco Nieddu, Silvia Ricci, Chiara Azzari, Giuseppe Indolfi Pediatric Pulmonology, 2025 AimExamine the trends and epidemiological features of acute hospitalized bronchiolitis cases among children aged 28 days to 2 years, both before and after the COVID‐19 pandemic. Furthermore, evaluate their need for intensive care unit (ICU) admission and identify primary risk factors associated with severe bronchiolitis.MethodsA retrospective analysis was conducted on the medical records of paediatric patients admitted to Meyer Children's Hospital in Florence (Italy) from September 2019 to March 2023, with the diagnosis of bronchiolitis.ResultsBetween 2019 and 2023, bronchiolitis hospitalizations grew by 76%, going from 131 to 230 cases, after the historical minimum of 14 cases in the 2020–2021 season. Respiratory syncytial virus (RSV) infection emerged as the predominant etiological agent, contributing to 76% of hospitalizations in both 2021–2022 and 2022–2023 seasons. Coinfection cases increased fivefold from 2019 to 2023, accounting for 23% of hospitalizations in 2022–2023. In addition, the ICU admission rate increased from 13% in 2019–2020 to 31% of bronchiolitis hospitalizations in 2022–2023. Univariate and multivariate analysis data show that infants below 2 months of age, preterm births, comorbidities and RSV infections were correlated with a higher risk for ICU admission.ConclusionThe growing trend in ICU admissions for acute bronchiolitis in hospitalized children represents a substantial health challenge. Addressing the bronchiolitis epidemic necessitates a strategic focus on RSV prevention through interventions such as vaccines and monoclonal antibodies. Urgent implementation of preventive initiatives, together with continuous surveillance and the establishment of national databases, is imperative and cannot be further deferred.
Serotype 3 invasive pneumococcal disease in Tuscany across the eras of conjugate vaccines (2005–2024) and anthropic-driven respiratory virus fluctuations Lorenzo Lodi, Francesco Catamerò, Walter Maria Sarli, Maria Moriondo, Francesco Nieddu, Emanuela Ferraro, Francesco Citera, Valeria Astorino, Mattia Giovannini, Marta Voarino, Caterina Pelosi, Francesca Quaranta, Francesca Lippi, Clementina Canessa, Silvia Ricci, Chiara Azzari Human Vaccines and Immunotherapeutics, 2025 = .0019). Ser3 IPD showed a strong temporal association with influenza virus outbreak but not with isolated RSV outbreak. Nearly two decades of molecular surveillance of ser3 in Tuscany suggest that the most severe IPD presentations, such as sepsis and meningitis, are significantly lower in individuals who received PCVser3 immunization. Ser3 IPD incidence is temporally associated with influenza outbreaks but not with RSV.
The impact of nirsevimab prophylaxis on RSV hospitalizations: a real-world cost-benefit analysis in Tuscany, Italy Vieri Lastrucci, Martina Pacifici, Giorgia Alderotti, Monia Puglia, Elettra Berti, Federica Barbati, Lorenzo Lodi, Silvia Boscia, Francesco Nieddu, Giuseppe Indolfi, Diego Peroni, Marco Martini, Chiara Azzari, Fabio Voller, Maria Moriondo, Silvia Ricci Frontiers in Public Health, 2025 BackgroundRespiratory Syncytial Virus (RSV) is the leading cause of hospitalizations in infants. The approval of nirsevimab, a long-acting monoclonal antibody, has extended the potential for RSV prophylaxis to all infants. This study assesses the cost–benefit of various Nirsevimab prophylaxis strategies for infants during their first RSV season in preventing RSV-associated hospitalization in the Tuscany region, Italy.MethodsThe analysis was conducted from the perspective of the healthcare payor. Real-world data from the Tuscany birth cohort (N = 21,017) experiencing their first RSV season in the 2023/2024 season were used to calculate the net benefit and benefit cost ratio (BCR) of three possible nirsevimab prophylaxis strategies compared with prophylaxis practices at the time of the study, which includes the use of palivizumab in eligible infants. RSV-associated hospitalizations and severe hospitalizations were considered as health outcomes. Sensitivity analyses were performed to identify influential variables.ResultsUnder prophylaxis practices at the time of the study, there were a total of 663 hospitalizations associated with RSV, including 102 severe cases, representing €5,247,645 in costs. An extended prophylaxis strategy with nirsevimab, including all infants born both before and during the RSV season, resulted in the highest number of hospitalizations avoided (378), with a BCR close to break-even (0.96). A seasonal-only strategy targeting infants born during the season prevented the fewest hospitalizations (252), showing a positive BCR of 1.15. Finally, a seasonal strategy with targeted catch-up, including also preterm infants born before the season, yielded the highest cost–benefit ratio (1.56), preventing 270 hospitalizations.ConclusionUniversal prophylaxis strategies with nirsevimab, targeting all infants during their first RSV epidemic season, substantially reduce hospitalization burdens without increasing economic pressure on the healthcare system. Although alternative strategies are more cost-effective, they prevent fewer hospitalizations, emphasizing the public health value of broader prophylaxis approaches.
Four-Component Recombinant Protein-Based Vaccine Effectiveness Against Serogroup B Meningococcal Disease in Italy Lorenzo Lodi, Federica Barbati, Daniela Amicizia, Vincenzo Baldo, Anna Maria Barbui, Alessandro Bondi, Claudio Costantino, Liviana Da Dalt, Lorenza Ferrara, Francesca Fortunato, Valentina Guarnieri, Giancarlo Icardi, Giuseppe Indolfi, Domenico Martinelli, Marco Martini, Maria Moriondo, Francesco Nieddu, Diego G. Peroni, Rosa Prato, Silvia Ricci, Francesca Russo, Francesca Tirelli, Francesco Vitale, Shamez N. Ladhani, Chiara Azzari, Mario Palermo, Girolama Bosco, Rosanna Milisenna, Mario Cuccia, Franco Belbruno, Giulia Tarabini Castellani, Claudio D’Angelo, Giuseppe Ferrera, Lia Contrino, Gaspare Canzoneri, Onofrio Mongelli, Nehludoff Albano, Domenico Lagravinese, Riccardo Matera, Stefano Termite, Giovanni Iannucci, Alberto Fedele, Michele Conversano, Irene Amoruso, Tatjana Baldovin, Silvia Cocchio, Nicole Bonaccorso, Martina Sciortino, Arianna Conforto, Susanna Masiero, Daniela Lombardi, Elisa Di Maggio, Martina Meola, Silvia Boscia, Michele Tonon, Marzio Masini, Maria Francesca Piazza, Camilla Sticchi, and JAMA Network Open, 2023
Factors that negatively affect the prognosis of pediatric community-acquired pneumonia in district hospital in Tanzania Serena Caggiano, Nicola Ullmann, Elisa De Vitis, Marzia Trivelli, Chiara Mariani, Maria Podagrosi, Fabiana Ursitti, Chiara Bertolaso, Carolina Putotto, Marta Unolt, Andrea Pietravalle, Paola Pansa, Kajoro Mphayokulela, Maria Lemmo, Michael Mkwambe, Joseph Kazaura, Marzia Duse, Francesco Nieddu, Chiara Azzari, Renato Cutrera International Journal of Molecular Sciences, 2017
Underestimation of invasive meningococcal disease in Italy Chiara Azzari, Francesco Nieddu, Maria Moriondo, Giuseppe Indolfi, Clementina Canessa, Silvia Ricci, Leila Bianchi, Daniele Serranti, Giovanni Maria Poggi, Massimo Resti Emerging Infectious Diseases, 2016
