Human Metapneumovirus Infections during COVID-19 Pandemic, Spain.

We describe an unusual outbreak of respiratory infections caused by human metapneumovirus in children during the sixth wave of COVID-19 in Spain, associated with the Omicron variant. Patients in this outbreak were older than usual and showed more hypoxia and pneumonia, longer length of stay, and greater need for intensive care.

Efficacy of nirsevimab against respiratory syncytial virus lower respiratory tract infections in preterm and term infants, and pharmacokinetic extrapolation to infants with congenital heart disease and chronic lung disease: a pooled analysis of randomised controlled trials.

BACKGROUND: In a phase 2b trial and the phase 3 MELODY trial, nirsevimab, an extended half-life, monoclonal antibody against respiratory syncytial virus (RSV), protected healthy infants born preterm or at full term against medically attended RSV lower respiratory tract infection (LRTI). In the MEDLEY phase 2-3 trial in infants at higher risk for severe RSV infection, nirsevimab showed a similar safety profile to that of palivizumab. The aim of the current analysis was to assess the efficacy of nirsevimab using a weight-banded dosing regimen in infants born between 29 weeks gestational age and full term. METHODS: Infants enrolled in the phase 2b and MELODY trials were randomised (2:1) to receive a single intramuscular injection of nirsevimab (infants weighing <5 kg received 50 mg; those weighing ≥5 kg received 100 mg) or placebo before the RSV season. Infants in MEDLEY were randomised (2:1) to receive one dose of nirsevimab (infants weighing <5 kg received 50 mg; those weighing ≥5 kg received 100 mg) followed by four monthly placebo doses, or five once-a-month intramuscular doses of palivizumab. We report a prespecified pooled efficacy analysis assessing the weight-banded dosing regimen proposed on the basis of the phase 2b and MELODY trials, in addition to extrapolated efficacy in infants with chronic lung disease, congenital heart disease, or extreme preterm birth (<29 weeks' gestational age) based on pharmacokinetic data from the phase 2-3 MEDLEY safety trial. For the pooled efficacy analysis, the primary endpoint was incidence of medically attended RSV LRTI through 150 days post-dose. The secondary efficacy endpoint was number of admissions to hospital for medically attended RSV LRTI. The incidence of very severe RSV LRTI was an exploratory endpoint, defined as cases of hospital admission for medically attended RSV LRTI that required supplemental oxygen or intravenous fluids. We also did a prespecified exploratory analysis of medically attended LRTI of any cause (in the investigator's judgement) and hospital admission for respiratory illness of any cause (defined as any upper respiratory tract infection or LRTI leading to hospital admission). Post hoc exploratory analyses of outpatient visits and antibiotic use were also done. Nirsevimab serum concentrations in MEDLEY were assessed using population pharmacokinetic methods and the pooled data from the phase 2b and MELODY trials. An exposure target was defined on the basis of an exposure-response analysis. To successfully demonstrate extrapolation, more than 80% of infants in MEDLEY had to achieve serum nirsevimab exposures at or above the predicted efficacious target. FINDINGS: Overall, 2350 infants (1564 in the nirsevimab group and 786 in the placebo group) in the phase 2b and MELODY trials were included in the pooled analysis. Nirsevimab showed efficacy versus placebo with respect to the primary endpoint of medically attended RSV LRTI (19 [1%] nirsevimab recipients vs 51 [6%] placebo recipients; relative risk reduction [RRR] 79·5% [95% CI 65·9-87·7]). Consistent efficacy was shown for additional endpoints of RSV LRTI hospital admission (nine [1%] nirsevimab recipients vs 21 [3%] placebo recipients; 77·3% [50·3-89·7]) and very severe RSV (five [<1%] vs 18 [2%]; 86·0% [62·5-94·8]). Nirsevimab recipients had fewer hospital admissions for any-cause respiratory illness (RRR 43·8% [18·8-61·1]), any-cause medically attended LRTI (35·4% [21·5-46·9]), LRTI outpatient visits (41·9% [25·7-54·6]), and antibiotic prescriptions (23·6% [3·8-39·3]). Among infants with chronic lung disease, congenital heart disease, or extreme preterm birth in MEDLEY, nirsevimab serum exposures were similar to those found in the pooled data; exposures were above the target in more than 80% of the overall MEDLEY trial population (94%), including infants with chronic lung disease (94%) or congenital heart disease (80%) and those born extremely preterm (94%). INTERPRETATION: A single dose of nirsevimab protected healthy infants born at term or preterm from medically attended RSV LRTI, associated hospital admission, and severe RSV. Pharmacokinetic data support efficacy extrapolation to infants with chronic lung disease, congenital heart disease, or extreme prematurity. Together, these data suggest that nirsevimab has the potential to change the landscape of infant RSV disease by reducing a major cause of infant morbidity and the consequent burden on caregivers, clinicians, and health-care providers. FUNDING: AstraZeneca and Sanofi.

Respiratory morbidity associated with viral respiratory infections during neonatal stage in premature infants.

BACKGROUND AND OBJECTIVE: Very low birth weight (VLBW) infants are highly susceptible to viral respiratory infections (VRIs), even during admission to the neonatal intensive care unit (NICU). Although the role of VRI in childhood in the development of recurrent wheezing and long-term asthma is well known, information on the impact in later morbidity of VRI in the neonatal period is lacking. We aimed to explore the occurrence of recurrent wheezing over the first 2 years of life according to VRI status during NICU admission. METHODS: During April 2016 and December 2017, infants below 32 weeks of gestation were prospectively studied in VRI surveillance during NICU admission. Families were contacted between September 2018 and May 2019 by a telephone questionnaire. RESULTS: A total of 99 patients were enrolled. The mean gestational age and birth weight were 28.8 (1.9) weeks and 1118 (329) g, respectively. During the first 2 years of life, neither episodes of wheezing nor the respiratory impairment-related hospital admissions differed between positive and negative VRI infants. Episodes of wheezing and respiratory impairment-related hospital admissions, as well as specific respiratory treatment prescription, were more frequent within the first 2 years in infants who had suffered symptomatic VRI during NICU admission. CONCLUSION: Symptomatic VRI in VLBW infants is associated with long-term respiratory morbidity. The early surveillance of VRI in the preterm infant during NICU admission is justified for prognostic counseling and closely monitoring after discharge. Routine instruction on asthma-related risk factors and early prescription of antiasthmatic treatments, when indicated, should be established.

Respiratory outcomes of "new" bronchopulmonary dysplasia in adolescents: A multicenter study.

OBJECTIVE: Long-term respiratory consequences of bronchopulmonary dysplasia (BPD) in preterm infants born in the post-surfactant era ("new" BPD) remain partially unknown. The present study aimed to evaluate the respiratory outcomes of "new" BPD in adolescents who were born preterm. METHODS: This multicenter, cross-sectional study included 286 adolescents born between 2003 and 2005 (mean age: 14.2 years); among them, 184 and 102 were born extremely preterm (EP; <28 weeks' gestation) and moderate-late preterm (32 to <37 weeks' gestation), respectively. Among EP adolescents, 92 had BPD, and 92 did not. All participants underwent lung function tests, skin prick testing, and questionnaires on asthma symptoms and quality of life. RESULTS: EP adolescents with BPD had significantly lower forced expiratory volume in 1 s (FEV1 ), forced vital capacity (FVC), FEV1 /FVC ratio, and forced expiratory flow between 25% and 75% of FVC than other included adolescents. FEV1 /FVC ratios were below the lower limit of normal (z-score <-1.645) in 30.4% of EP adolescents with BPD, 13.0% of EP adolescents without BPD, and 11.8% of adolescents who were born moderate-late preterm. Bronchodilator response and air-trapping were significantly higher in BPD adolescents than in other adolescents. Diffusion capacity was significantly lower in EP adolescents than in moderate-late preterm adolescents. Asthma symptoms and quality-of-life scores were similar among groups. CONCLUSION: EP adolescents with "new" BPD had poorer pulmonary function than EP adolescents without BPD or moderate-late preterm adolescents. Further studies are needed to determine whether "new" BPD is associated with early-onset chronic obstructive pulmonary disease in adulthood.

Prevalence of Celiac Disease in a Long-term Study of a Spanish At-genetic-risk Cohort From the General Population.

OBJECTIVES: To perform long-term celiac disease (CD) screening in an HLA-DQ2 (+) cohort from the general population and to assess the influence of risk genotypes on its development. METHODS: In 2004, an HLA-DQ2 (+) cohort was selected. After the first CD screening at age 2 to 3 years, we performed a follow-up screening 8 to 10 years later. Antitransglutaminase 2 antibodies were determined using a rapid test kit. Results were confirmed by serum IgA antitransglutaminase 2 and IgA endomysial antibody determination. CD diagnosis was carried out by intestinal biopsies. Four HLA-DQ2 genotypic groups were used: G1: DQ2.5/DQ2.5 (G1A) or DQ2.5/ DQ2.2 (G1B); G2: DQ2.2/DQ7.5 (DQ2.5 trans); G3: DQ2.5/ X; G4: DQ2.2/X. RESULTS: CD prevalence after 10 years of follow-up was 5.8% (95% confidence interval 3.8-8.7). One of every 3 HLA-DQ2(+) children carried at least 1 haplotype DQ2.2 or DQ7. The homozygous genotype DQ2.5/DQ2.5 and the HLA-DQ2.5 trans genotype increased CD risk 4- and 3-fold, respectively. The homozygous genotype DQ2.5/ DQ2.2 did not increase the CD risk. Children carrying G1 or G2 genotypes were diagnosed with CD earlier and more frequently during the follow-up compare with those carrying G3 or G4 genotypes. Approximately 81% of children with spontaneous antibody negativization after the first screening maintained negative antibodies. CONCLUSIONS: A repeated screening of at-risk children during their follow-up allowed us to diagnose new CD cases. In our cohort, HLA- DQ2.5 trans genotype conferred a higher risk in the development of CD than HLA- DQ2.5/DQ2.2. The majority of children with potential CD and CD autoimmunity at 10 years of age remained healthy.

Multidrug resistant pulmonary tuberculosis treatment regimens and patient outcomes: an individual patient data meta-analysis of 9,153 patients.

BACKGROUND: Treatment of multidrug resistant tuberculosis (MDR-TB) is lengthy, toxic, expensive, and has generally poor outcomes. We undertook an individual patient data meta-analysis to assess the impact on outcomes of the type, number, and duration of drugs used to treat MDR-TB. METHODS AND FINDINGS: Three recent systematic reviews were used to identify studies reporting treatment outcomes of microbiologically confirmed MDR-TB. Study authors were contacted to solicit individual patient data including clinical characteristics, treatment given, and outcomes. Random effects multivariable logistic meta-regression was used to estimate adjusted odds of treatment success. Adequate treatment and outcome data were provided for 9,153 patients with MDR-TB from 32 observational studies. Treatment success, compared to failure/relapse, was associated with use of: later generation quinolones, (adjusted odds ratio [aOR]: 2.5 [95% CI 1.1-6.0]), ofloxacin (aOR: 2.5 [1.6-3.9]), ethionamide or prothionamide (aOR: 1.7 [1.3-2.3]), use of four or more likely effective drugs in the initial intensive phase (aOR: 2.3 [1.3-3.9]), and three or more likely effective drugs in the continuation phase (aOR: 2.7 [1.7-4.1]). Similar results were seen for the association of treatment success compared to failure/relapse or death: later generation quinolones, (aOR: 2.7 [1.7-4.3]), ofloxacin (aOR: 2.3 [1.3-3.8]), ethionamide or prothionamide (aOR: 1.7 [1.4-2.1]), use of four or more likely effective drugs in the initial intensive phase (aOR: 2.7 [1.9-3.9]), and three or more likely effective drugs in the continuation phase (aOR: 4.5 [3.4-6.0]). CONCLUSIONS: In this individual patient data meta-analysis of observational data, improved MDR-TB treatment success and survival were associated with use of certain fluoroquinolones, ethionamide, or prothionamide, and greater total number of effective drugs. However, randomized trials are urgently needed to optimize MDR-TB treatment. Please see later in the article for the Editors' Summary.

Pandemic H1N1 influenza-associated hospitalizations in children in Madrid, Spain.

OBJECTIVE: To describe the epidemiological and clinical characteristics of children hospitalized with 2009 pandemic influenza (pH1N1) in Madrid, Spain. PATIENTS/METHODS: We included patients less than 14 years of age admitted to one of 18 hospitals in Madrid, Spain, between May 1 and November 30, 2009 and diagnosed with pH1N1 by polymerase chain reaction. A retrospective chart review was conducted and data were compared by age, presence of high-risk medical conditions, and pediatric intensive care unit (PICU) admission. RESULTS: A total of 517 pH1N1 cases were included for final analysis. One hundred and forty-two patients (27·5%) had predisposing underlying illnesses, with immunosuppression (36 children, 7%) and moderate persistent asthma (34, 6·6%) being the most common ones. Patients with underlying medical conditions had longer hospital stays [median 5, interquartile range (IQR) 3-8 days, versus median 4, IQR 3-6, P < 0·001] and required intensive care (20·4% versus 5·9%, P < 0·001) and mechanical ventilation more frequently than previously healthy children. Globally, intensive care was required for 51 patients (10%) and invasive mechanical ventilation for 12 (2%). Pediatric intensive care unit admission was significantly associated with abnormal initial chest X-ray [Odds Ratio (OR) 3·5, 95% confidence interval (CI) 1·5-8·5], underlying neurological condition (OR 3·1, CI 1·2-7·5) and immunosuppression (OR 2·9, 1·2-6·8). Five patients (0·9%) died; two with severe neurological disease, two with leukemia, and one with a malignant solid tumor. CONCLUSIONS: Children with underlying medical conditions experienced more severe pH1N1 disease. Risk factors for admission to the PICU included underlying neurological conditions, immunosuppression and abnormal initial chest X-ray.

Ten years of global evolution of the human respiratory syncytial virus BA genotype with a 60-nucleotide duplication in the G protein gene.

The emergence of natural isolates of human respiratory syncytial virus group B (HRSV-B) with a 60-nucleotide (nt) duplication in the G protein gene in Buenos Aires, Argentina, in 1999 (A. Trento et al., J. Gen. Virol. 84:3115-3120, 2003) and their dissemination worldwide allowed us to use the duplicated segment as a natural tag to examine in detail the evolution of HRSV during propagation in its natural host. Viruses with the duplicated segment were all clustered in a new genotype, named BA (A. Trento et al., J. Virol. 80:975-984, 2006). To obtain information about the prevalence of these viruses in Spain, we tested for the presence of the duplicated segment in positive HRSV-B clinical samples collected at the Severo Ochoa Hospital (Madrid) during 12 consecutive epidemics (1996-1997 to 2007-2008). Viruses with the 60-nt duplication were found in 61 samples, with a high prevalence relative to the rest of B genotypes in the most recent seasons. Global phylogenetic and demographic analysis of all G sequences containing the duplication, collected across five continents up until April 2009, revealed that the prevalence of the BA genotype increased gradually until 2004-2005, despite its rapid dissemination worldwide. After that date and coinciding with a bottleneck effect on the population size, a relatively new BA lineage (BA-IV) replaced all other group B viruses, suggesting further adaptation of the BA genotype to its natural host.

[Respiratory infections due to metapneumovirus in hospitalized infants]. / Infecciones respiratorias por metapneumovirus en lactantes hospitalizados.

BACKGROUND: Human metapneumovirus (hPMV) is a recently identified virus that is recognized as a cause of respiratory tract illness in the pediatric population. OBJECTIVES: To determine the incidence of respiratory tract infections caused by hPMV in hospitalized infants and to describe the clinical characteristics and possible presence of coinfection with other viral agents. PATIENTS AND METHODS: We performed a prospective study from September to June 2003 in all children aged less than 24 months who were admitted to the Severo Ochoa Hospital (Leganés, Madrid) with a respiratory tract infection. Virological diagnosis was made with a direct immunofluorescent assay and/or reverse transcriptase-polymerase chain reaction on specimens obtained from nasopharyngeal washing. Demographic and clinical data from patients with an hPMV respiratory tract infection were analyzed. RESULTS: During the study period, 200 infants were admitted with a respiratory tract infection, of which 18 (9 %) had an hPMV infection. HPMV was the viral agent isolated in 13.8 % of positive nasopharyngeal washings. All patients were admitted between March and April. The mean age was 6.7 +/- 6.1 months. The most common diagnoses were recurrent wheezing (55.5 %) and bronchiolitis (38.8 %). Oxygen therapy was required by 55.5 % of infants during hospitalization. Coinfection with other respiratory viruses was confirmed in 33.3 % of the patients. CONCLUSIONS: Human metapneumovirus is a major cause of respiratory tract illness in hospitalized infants. This virus causes mainly bronchiolitis and recurrent wheezing and is more frequent in spring. Coinfection with other respiratory viruses is frequent.

[Chest radiograph in bronchiolitis: is it always necessary?]. / Radiografía de tórax en la bronquiolitis: es siempre necesaria?

BACKGROUND: The routine use of chest radiograph in infants with bronchiolitis increases health costs and can often unnecessarily expose the patient to radiation. OBJECTIVES: To evaluate the prevalence of infiltrate/atelectasis in infants younger than 2 years who presented to the emergency department with bronchiolitis, to assess whether patient management is changed after viewing the chest radiograph and to determine which clinical variables can accurately identify children with normal radiographs, with a view to reducing unnecessary radiological investigations. PATIENTS AND METHODS: From October 2003 to December 2004, infants aged < 24 months evaluated in the emergency department of the Severo Ochoa Hospital (Madrid) with a diagnosis of bronchiolitis were included in this study. The variables registered were age, sex, time since onset, respiratory rate, temperature, asymmetry on auscultation, oxygen saturation and the virus identified. A chest radiograph was obtained and the need for admission was evaluated before and after obtaining the results. RESULTS: Two hundred fifty-two infants were included, of which 50 % were aged less than 5 months. Infiltrate/atelectasis was identified in 14.3 % (95 % CI: 10.1-18.5; kappa coefficient: 0.64). Patients with infiltrate/atelectasis were 2.5 times more likely to have a temperature of > or = 38 degrees C (p: 0.004), O2 saturation of < 94 % (p: 0,006) and to be admitted before the results of chest radiograph were known. No differences were found between children with and without infiltrate in age at presentation, sex, disease duration, respiratory rate or identified virus. Patient management was modified in 30 % of patients with infiltrate/ atelectasis. Patients with a temperature of < 38 degrees and O2 saturation of > 94 % had a 92 % probability of normal chest radiograph. CONCLUSIONS: Most infants presenting with bronchiolitis had a normal chest radiograph. Temperature >or = 38 degrees and O2 saturation < 94 % were significantly associated with infiltrate/atelectasis. In most infants with bronchiolitis, the absence of fever and hypoxia are good predictors of normal chest radiographs.