IMPORTANCE Excessive antibiotic use has been associated with altered bacterial colonization and may result in antibiotic resistance, fungemia, necrotizing enterocolitis (NEC), and mortality. Exploring the association between antibiotic exposure and neonatal outcomes other than infection-related morbidities may provide insight on the importance of rational antibiotic use, especially in the setting of culture-negative neonatal sepsis. OBJECTIVE To evaluate the trend of antibiotic use among all hospitalized very low-birth-weight (VLBW) infants across Canada and the association between antibiotic use rates (AURs) and mortality and morbidity among neonates without culture-proven sepsis or NEC. DESIGN, SETTING, AND PARTICIPANTS A retrospective cohort study was conducted among VLBW infants (<1500 g) admitted to level III neonatal intensive care units between January 1, 2010, and December 31, 2014, using data obtained from the Canadian Neonatal Network database. EXPOSURE Duration of antibiotic use during the hospitalization period. MAIN OUTCOMES AND MEASURES The AUR was defined as the number of days an infant was exposed to 1 or more antimicrobial agents divided by the total length of hospital stay. The composite primary outcome was defined as mortality or major morbidity, including any of the following: persistent periventricular echogenicity or echolucency on neuroimaging, chronic lung disease, and stage 3 or higher retinopathy of prematurity. Multivariable regression analysis was used to calculate adjusted odds ratios (aORs) and 95% CIs for the association between AURs and outcomes. RESULTS Among 13 738 eligible VLBW infants, 11 669 (84.9%) (mean [SD] gestational age, 27.7 [2.5] weeks; 47.4% female) received antibiotics during their hospital course and were included in the study. The annual AUR decreased from 0.29 in 2010 to 0.25 in 2014 (slope for the best-fit line, −0.011; 95% CI, −0.016 to −0.006; P < .01), which occurred in parallel with a reduction in the rate of late-onset sepsis from 19.0% in 2010 to 13.8% in 2014 during the same period. Of the 11 669 infants who were treated with antibiotics of varying duration during their hospital stay, 2845 were diagnosed as having sepsis-related complications. Among the remaining 8824 infants without early-onset sepsis, late-onset sepsis, or NEC, a 10% increase in the AUR was associated with an increased odds of the primary composite outcome (aOR, 1.18; 95% CI, 1.13-1.23), mortality (aOR, 2.04; 95% CI, 1.87-2.21), and stage 3 or higher retinopathy of prematurity (aOR, 1.18; 95% CI, 1.06-1.32). CONCLUSIONS AND RELEVANCE Antibiotic use in VLBW infants decreased between 2010 and 2014 in Canada. However, among infants without culture-proven sepsis or without NEC, higher AURs were associated with adverse neonatal outcomes.

IMPORTANCEThere are limited high-quality, population-level data about the effect of SARS-CoV-2 infection on pregnancy using contemporaneous comparator cohorts.OBJECTIVES To describe maternal and perinatal outcomes associated with SARS-CoV-2 infection in pregnancy and to assess variables associated with severe disease in the pregnant population.DESIGN, SETTING, AND PARTICIPANTS CANCOVID-Preg is an observational surveillance program for SARS-CoV-2-affected pregnancies in Canada. This analysis presents exploratory, population-level data from 6 Canadian provinces for the period of March 1, 2020, to October 31, 2021. A total of 6012 pregnant persons with a positive SARS-CoV-2 polymerase chain reaction test result at any time in pregnancy (primarily due to symptomatic presentation) were included and compared with 2 contemporaneous groups including age-matched female individuals with SARS-CoV-2 and unaffected pregnant persons from the pandemic time period.EXPOSURE SARS-CoV-2 infection during pregnancy. Incident infections in pregnancy were reported to CANCOVID-Preg by participating provinces/territories. MAIN OUTCOMES AND MEASURESMaternal and perinatal outcomes associated with SARS-CoV-2 infection as well as risk factors for severe disease (ie, disease requiring hospitalization, admission to an intensive care unit/critical care unit, and/or oxygen therapy). RESULTS Among 6012 pregnant individuals with SARS-CoV-2 in Canada (median age, 31 [IQR, 28-35] years), the greatest proportion of cases were diagnosed at 28 to 37 weeks' gestation (35.7%). Non-White individuals were disproportionately represented. Being pregnant was associated with a significantly increased risk of SARS-CoV-2-related hospitalization compared with SARS-CoV-2 cases among all women aged 20 to 49 years in the general population of Canada (7.75% vs 2.93%; relative risk, 2.65 [95% CI, 2.41-2.88]) as well as an increased risk of intensive care unit/critical care unit admission (2.01% vs 0.37%; relative risk, 5.46 [95% CI, 4.50-6.53]). Increasing age, preexisting hypertension, and greater gestational age at diagnosis were significantly associated with worse maternal outcomes. The risk of preterm birth was significantly elevated among SARS-CoV-2-affected pregnancies (11.05% vs 6.76%; relative risk, 1.63 [95% CI, 1.52-1.76]), even in cases of milder disease not requiring hospitalization, compared with unaffected pregnancies during the same time period. CONCLUSIONS AND RELEVANCEIn this exploratory surveillance study conducted in Canada from March 2020 to October 2021, SARS-CoV-2 infection during pregnancy was significantly associated with increased risk of adverse maternal outcomes and preterm birth.

and GBS remain the most common causes of bacterial meningitis in the first 90 days of life. For empirical therapy of suspected bacterial meningitis, one should consider a third-generation cephalosporin (plus ampicillin for at least the first month), potentially substituting a carbapenem for the cephalosporin if there is evidence for Gram-negative meningitis.

on behalf of the Canadian Neonatal Network Investigators abstract BACKGROUND: Overuse of antibiotics can facilitate antibiotic resistance and is associated with adverse neonatal outcomes. We studied the association between duration of antibiotic therapy and short-term outcomes of very low birth weight (VLBW) (,1500 g) infants without cultureproven sepsis.