Developmental Impairment in Children Exposed to Sars-Cov-2 in Utero: A Brazilian Cohort Study. (preprint)

Background The effects of in-utero exposure to maternal SARS-CoV-2 infection on the offspring's neurodevelopment are still unknown.Methods We performed a prospective cohort of babies exposed to SARS-Cov-2 during pregnancy, and a control group of unexposed babies in a low-income area in Northeastern Brazil. All data were prospectively collected from medical records. Children’s neurodevelopment was assessed using the guide for Monitoring Child Development in the IMCI context and the Ages & Stages Questionnaire (ASQ-3), at ages 4, 6, and 12 months. Maternal depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale (EPDS).Results We followed 127 children for one year, 69 children in the COVID-19 exposed Group (EG), and 68 in the control group (CG). All mothers were unvaccinated at the time included in the cohort. Maternal demographics were similar in the two groups, but prematurity was more prevalent in mothers infected with COVID-19 (21.7% vs. 8.8%, p = .036) and EPDS scores were also significantly higher among the EG (M = 11.00, SD = 6.00 vs. M = 8.68, SD = 4.72, p = 0.04). Both groups had similar rates of cesarean delivery, Apgar scores, average birth weight, head circumference and length at birth. 20.3% of EG children and 5.9% of the CG received a diagnosis of neurodevelopmental delay within 12 months of life (p = 0.013, RR = 3.44; 95% CI, 1.19–9.95). 10% of EG children presented abnormalities at the cranial ultrasound.Conclusions COVID-19 exposure was associated with neurodevelopmental impairment. This study highlights the importance of specific guidelines in the follow-up of children exposed to in-utero SARS-CoV-2 in order to mitigate or prevent long-term effects on children’s health.

The role of airborne transmission in a large single source outbreak of SARS-CoV-2 in a Belgian nursing home in 2020.

OBJECTIVES: To better understand the conditions which have led to one of the largest COVID-19 outbreaks in Belgian nursing homes in 2020. SETTING: A nursing home in Flanders, Belgium, which experienced a massive outbreak of COVID-19 after a cultural event. An external volunteer who dressed as a legendary figure visited consecutively the 4 living units on December, 4th and tested positive for SARS-CoV-2 the next day. Within days, residents started to display symptoms and the outbreak spread rapidly within the nursing home. METHODS: We interviewed key informants and collected standardized data from all residents retrospectively. A batch of 115 positive samples with a Ct value of < 37 by qRT-PCR were analyzed using whole-genome sequencing. Six months after the outbreak, ventilation assessment of gathering rooms in the nursing home was done using a tracer gas test with calibrated CO2 sensors. RESULTS: Timeline of diagnoses and symptom onsets clearly pointed to the cultural event as the start of the outbreak, with the volunteer as index case. The genotyping of positive samples depicted the presence of one large cluster, suggesting a single source outbreak. By the end of December, a total of 127 residents and 40 staff were diagnosed with SARS-CoV-2 since the beginning of the outbreak. The attack rate among residents was 77 % and significantly associated with presence at the event but not with close contact or mask wearing. The ventilation assessment showed a high background average CO2 level in four main rooms varying from 657 ppm to 846 ppm. CONCLUSIONS: Our investigation shows a rapid and widespread single source outbreak of SARS-CoV-2 in a nursing home, in which airborne transmission was the most plausible explanation for the massive intra-facility spread. Our results underscore the importance of ventilation and air quality for the prevention of future outbreaks in closed facilities.

The role of airborne transmission in a large single source outbreak of SARS-CoV-2 in a Belgian nursing home in 2020 (preprint)

Abstract Objectives: To better understand the conditions which have led to one of the largest COVID-19 outbreaks in Belgian nursing homes in 2020. Setting: A nursing home in Flanders, Belgium, which experienced a massive outbreak of COVID-19 after a cultural event. An external volunteer who dressed as a legendary figure visited consecutively the 4 living units and tested positive for SARS-CoV-2 the next day. Within days, residents started to display symptoms and the outbreak spread rapidly within the nursing home. Methods: We interviewed key informants and collected standardized data from all residents retrospectively. A batch of 115 positive samples with a Ct value of <37 by qRT-PCR were analysed using whole-genome sequencing. Six months after the outbreak, ventilation assessment of gathering rooms in the nursing home was done using a tracer gas test with calibrated CO2 sensors. Results: Timeline of diagnoses and symptom onsets clearly pointed to the cultural event as the start of the outbreak, with the volunteer as index case. The genotyping of positive samples depicted the presence of one large cluster, suggesting a single source outbreak. The global attack rate among residents was 77% with a significant association between infection and presence at the event. Known risk factors such as short distance to or physical contact with the volunteer, and wearing of a mask during the event were not associated with early infection. The ventilation assessment showed a high background average CO2 level in four main rooms varying from 657 ppm to 846 ppm. Conclusions: Our investigation shows a rapid and widespread single source outbreak of SARS-CoV-2 in a nursing home, in which airborne transmission was the most plausible explanation for the massive intra-facility spread. Our results underscore the importance of ventilation and air quality for the prevention of future outbreaks in closed facilities.