Backgrounds:

We aim to describe outcomes (focusing on hearing and neurological findings) and transfer of maternal antibodies in infants born from mothers with SARS-CoV-2 infection during pregnancy.

Methods:

Observational prospective study performed in a tertiary hospital in Madrid (Spain). Infants born from mothers with SARS CoV-2 infection during pregnancy from March to September 2020 were included. SARS-CoV-2 RT-PCT on nasopharyngeal swab (NPS) was performed at birth to infants born from mother with acute infection at delivery. A follow-up visit with physical and neurological examination, SARS-CoV-2 RT-PCR on NPS, SARS-CoV-2 serology, and a cranial ultrasound (cUS) was performed within 3 months of life. Automated auditory brainstem response (A-ABR) exams were performed at birth, and auditory steady-state response (ASSR) at six months of life.

Results:

95 infants born from 94 mothers were included. Median gestational age was 39+3 (IQR 38-40) and 10 (10.5%) were preterm. Thirteen (13.7%) newborns required hospital admission after birth, none of them with a COVID-19 infection. Rates of vertical (1/28; 3.6%) and horizontal (1/93; 1.1%) transmitted infections were low, with mild symptoms. In follow-up visit, neurological examination was normal in all infants. Cranial ultrasound was normal in 81/85 (95.3%) infants, with mild abnormalities in four infants. 47/ 95 (50%) infants had a positive serology. Serology result was not related to the severity of the maternal infection, skin-to-skin care at birth or breastfeeding. There was a progressive decrease in SARS-CoV-2 antibody titers with the age (figure 1). No hearing loss was detected.

Conclusions/Learning Points:

In this cohort, most infants born from mothers with SARS-CoV-2 infection during pregnancy had normal cUS, hearing screening and neurological examinations in the follow-up. There is a rapid decrease in transferred maternal antibodies in the first months of life.

Backgrounds:

Multisystem inflammatory syndrome in children (MIS-C) is a condition characterized by a dysregulated response of the immune system 2-6 weeks after a SARS-CoV-2 infection. Some authors hypothesized that the COVID-19 vaccine could trigger a new exaggerated response in these children.

Our aim was to assess the proportion of vaccinated children and the incidence of new MIS-C or myocarditis after vaccination in adolescents with previous MIS-C.

Methods

From the Epidemiological Study of COVID-19 in Children of the Spanish Pediatric Association, we contacted researchers from centers with ≥3 MIS-C patients aged 12-18 years old by October 31, 2021, hospitalized from March 2020, through October 2021 and fulfilling WHO criteria for MIS-C.

We performed a semi-structured telephonic interview with the caregivers and/or the adolescents, about vaccination acceptance and adverse events after vaccination.

Results:

An interview was possible in 42/48 (87.5%) selected adolescents, being mainly male (30/42, 71.4%) and, at MIS-C diagnosis, their median age was 13.1 years old. 32/42 (76.2%) patients had received COVID-19 vaccine. The median time between MIS-C diagnosis and vaccination was 42 weeks and the telephonic interview took place after a median of 10.0 weeks (range 5.3-19.7) post-vaccination. After vaccination, 22/32 (68.8%) patients reported adverse events, being 86.7% mild and 3.3% moderate (Table1). No new MIS-C or myocarditis or pericarditis episodes were reported.

Conclusions/Learning Points:

In this study, we describe a high acceptance and low incidence of relevant adverse events after COVID-19 vaccines in a population of adolescents with a previous MIS-C diagnosis. No new MIS-C episodes or myocarditis occurred after a median of 10 weeks post-vaccination. The results of this study are reassuring and may help to decide for patients with previous MIS-C who are considering COVID-19 vaccination.