Third trimester placentitis: an underreported complication of SARS-CoV-2 infection.

SARS-CoV-2-related placentitis shows distinctive histologic characteristics, and its impact on perinatal outcomes is increasingly under scrutiny. We present two such cases in the third trimester displaying mild maternal clinical symptoms and associated with maternal coagulopathy, reduced fetal movements, and nonreassuring fetal heart rate tracing. Both cases resulted in emergency cesarean deliveries. Our cases and a review of the literature highlight that SARS-CoV-2 undermines placental function and thus greatly impacts late-term pregnancies, even in the absence of severe systemic disease.

Saliva for molecular detection of SARS-CoV-2 in pre-school and school-age children.

SARS-CoV-2 diagnosis is a cornerstone for the management of coronavirus disease 2019 (COVID-19). Numerous studies have assessed saliva performance over nasopharyngeal sampling (NPS), but data in young children are still rare. We explored saliva performance for SARS-CoV-2 detection by RT-PCR according to the time interval from initial symptoms or patient serological status. We collected 509 NPS and saliva paired samples at initial diagnosis from 166 children under 12 years of age (including 57 children under 6), 106 between 12 and 17, and 237 adults. In children under 12, overall detection rate for SARS-CoV-2 was comparable in saliva and NPS, with an overall agreement of 89.8%. Saliva sensitivity was significantly lower than that of NPS (77.1% compared to 95.8%) in pre-school and school-age children but regained 96% when considering seronegative children only. This pattern was also observed to a lesser degree in adolescents but not in adults. Sensitivity of saliva was independent of symptoms, in contrary to NPS, whose sensitivity decreased significantly in asymptomatic subjects. Performance of saliva is excellent in children under 12 at early stages of infection. This reinforces saliva as a collection method for early and unbiased SARS-CoV-2 detection and a less invasive alternative for young children.

Neuroinflammatory Disease following Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Children.

OBJECTIVE: To describe neurologic, radiologic and laboratory features in children with central nervous system (CNS) inflammatory disease complicating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. STUDY DESIGN: We focused on CNS inflammatory diseases in children referred from 12 hospitals in the Paris area to Necker-Sick Children Reference Centre. RESULTS: We identified 19 children who had a history of SARS-CoV-2 infection and manifest a variety of CNS inflammatory diseases: encephalopathy, cerebellar ataxia, acute disseminated encephalomyelitis, neuromyelitis optica spectrum disorder, or optic neuritis. All patients had a history of SARS-CoV-2 exposure, and all tested positive for circulating antibodies against SARS-CoV-2. At the onset of the neurologic disease, SARS-CoV-2 PCR results (nasopharyngeal swabs) were positive in 8 children. Cerebrospinal fluid was abnormal in 58% (11/19) and magnetic resonance imaging was abnormal in 74% (14/19). We identified an autoantibody co-trigger in 4 children (myelin-oligodendrocyte and aquaporin 4 antibodies), representing 21% of the cases. No autoantibody was found in the 6 children whose CNS inflammation was accompanied by a multisystem inflammatory syndrome in children. Overall, 89% of patients (17/19) received anti-inflammatory treatment, primarily high-pulse methylprednisolone. All patients had a complete long-term recovery and, to date, no patient with autoantibodies presented with a relapse. CONCLUSIONS: SARS2-CoV-2 represents a new trigger of postinfectious CNS inflammatory diseases in children.

The Coris BioConcept COVID 19 Ag Respi-Strip, a field experience feedback.

This communication described how the Coris BioConcept COVID-19 Ag Respi-Strip test (Coris-Ag) was implemented in the workflow of our clinical microbiology laboratory for COVID-19 diagnosis. The diagnostic performance statistics (sensitivity, specificity) of the Coris-Ag were evaluated against a gold standard, the RealStar SARS-CoV-2 RT-PCR kit 1.0. Additionally, the effect of reading the Coris-Ag results at 30 min was compared to reading at 15 min. The Coris-Ag was performed on a total of 294 patients during two periods; 158 patients were tested during period 1 at the peak of the pandemic (April 6th to April 10th 2020) which returned a positivity rate of 17.1 %, and 136 patients during period 2 (April 12th to April 16th 2020) which returned a positivity rate of 11 %. Compared to the RT-PCR, the 15-minute Coris-Ag readings resulted in a sensitivity of 59.3 % with a 100 % specificity for the period 1 patients (n = 158) while the sensitivity decreased to 20 % for the period 2 patients (n = 136). The overall sensitivity was 38.1 % for both periods (n = 294). The corresponding 30-minute readings produced a 7 % increase in sensitivity with a specificity of 100 % (n = 294). The sensitivity of the strip test (15-min reading) for high viral loads (Ct <25) was 84.6 %.

Weak antibody response to three doses of mRNA vaccine in kidney transplant recipients treated with belatacept.

Poor responses to mRNA COVID-19 vaccine have been reported after 2 vaccine injections in kidney transplant recipients (KTRs) treated with belatacept. We analyzed the humoral response in belatacept-treated KTRs without a history of SARS-CoV-2 infection who received three injections of BNT162b2-mRNA COVID-19 vaccine. We also investigated vaccine immunogenicity in belatacept-treated KTRs with prior COVID-19 and characterized symptomatic COVID-19 infections after the vaccine in belatacept-treated KTRs. Among the 62 belatacept-treated KTRs (36 [58%] males), the median age (63.5 years IQR [51-72]), without COVID-19 history, only four patients (6.4%) developed anti-SARS-CoV-2 IgG with low antibody titers (median 209, IQR [20-409] AU/ml). 71% were treated with mycophenolic acid and 100% with steroids in association with belatacept. In contrast, in all the 5 KTRs with prior COVID-19 history, mRNA vaccine induced a strong antibody response with high antibody titers (median 10 769 AU/ml, IQR [6410-20 069]) after two injections. Seroprevalence after three-vaccine doses in 35 non-belatacept-treated KTRs was 37.1%. Twelve KTRs developed symptomatic COVID-19 after vaccination, including severe forms (50% of mortality). Breakthrough COVID-19 occurred in 5% of fully vaccinated patients. Administration of a third dose of BNT162b2 mRNA COVID-19 vaccine did not improve immunogenicity in KTRs treated with belatacept without prior COVID-19. Other strategies aiming to improve patient protection are needed.

Impact of public health measures on the post-COVID-19 respiratory syncytial virus epidemics in France.

Since the beginning of the COVID-19 pandemic, other respiratory illnesses decreased worldwide. This study described the consequences of public health measures on respiratory syncytial virus (RSV) severe infections in France, where an interseasonal resurgence of RSV occurred recently. All patients admitted to Necker Hospital (Paris) between August 2018 and April 2021 with a diagnosis of RSV-associated acute lung respiratory infection (ALRI) were enrolled. Characteristics of subjects with RSV-associated ALRI in 2020/2021 were compared to those infected during the two previous outbreaks. Overall, 664 inpatients were diagnosed with RSV-associated ALRI: 229, 183, and 252 during the 2018/2019, 2019/2020, and 2020/2021 outbreaks, respectively. During autumn 2020, a national lockdown began in France but schools remained open. A 3-month delayed RSV epidemic occurred at the end of this lockdown. Compared to previous outbreaks, the 2020/2021 epidemics involved more children aged 6 to 11 months (25.8% versus 13.1%, p < 0.0001), but less infants aged < 6 months (41.3% versus 56.6%, p < 0.0001) and less adults (0.0 versus 2.7%, p < 0.0001). Shorter length of stay at hospital, less frequent requirement of admission to intensive care unit, use of non-invasive ventilation, and/or high-flow nasal oxygen were observed in 2020/2021 than during previous epidemics (p < 0.0001). Delayed RSV outbreak was associated with more hospitalizations for ALRI, higher age of pediatric inpatients, but milder median clinical phenotype. Reinforced public health measures (even while keeping nurseries and schools open with mandatory face masks since six years of age) could impact, at least transiently, the burden of RSV-related hospitalizations.

Prior infection by seasonal coronaviruses, as assessed by serology, does not prevent SARS-CoV-2 infection and disease in children, France, April to June 2020.

BackgroundChildren have a low rate of COVID-19 and secondary severe multisystem inflammatory syndrome (MIS) but present a high prevalence of symptomatic seasonal coronavirus infections.AimWe tested if prior infections by seasonal coronaviruses (HCoV) NL63, HKU1, 229E or OC43 as assessed by serology, provide cross-protective immunity against SARS-CoV-2 infection.MethodsWe set a cross-sectional observational multicentric study in pauci- or asymptomatic children hospitalised in Paris during the first wave for reasons other than COVID (hospitalised children (HOS), n = 739) plus children presenting with MIS (n = 36). SARS-CoV-2 antibodies directed against the nucleoprotein (N) and S1 and S2 domains of the spike (S) proteins were monitored by an in-house luciferase immunoprecipitation system assay. We randomly selected 69 SARS-CoV-2-seropositive patients (including 15 with MIS) and 115 matched SARS-CoV-2-seronegative patients (controls (CTL)). We measured antibodies against SARS-CoV-2 and HCoV as evidence for prior corresponding infections and assessed if SARS-CoV-2 prevalence of infection and levels of antibody responses were shaped by prior seasonal coronavirus infections.ResultsPrevalence of HCoV infections were similar in HOS, MIS and CTL groups. Antibody levels against HCoV were not significantly different in the three groups and were not related to the level of SARS-CoV-2 antibodies in the HOS and MIS groups. SARS-CoV-2 antibody profiles were different between HOS and MIS children.ConclusionPrior infection by seasonal coronaviruses, as assessed by serology, does not interfere with SARS-CoV-2 infection and related MIS in children.

Performance of 30 commercial SARS-CoV-2 serology assays in testing symptomatic COVID-19 patients.

We report evaluation of 30 assays' (17 rapid tests (RDTs) and 13 automated/manual ELISA/CLIA assay (IAs)) clinical performances with 2594 sera collected from symptomatic patients with positive SARS-CoV-2 rRT-PCR on a respiratory sample, and 1996 pre-epidemic serum samples expected to be negative. Only 4 RDT and 3 IAs fitted both specificity (> 98%) and sensitivity (> 90%) criteria according to French recommendations. Serology may offer valuable information during COVID-19 pandemic, but inconsistent performances observed among the 30 commercial assays evaluated, which underlines the importance of independent evaluation before clinical implementation.

Transmission Routes of Severe Acute Respiratory Syndrome Coronavirus 2 Among Healthcare Workers of a French University Hospital in Paris, France.

In this case-control study on 564 healthcare workers of a university hospital in Paris (France), contacts without protection with coronavirus disease 2019 (COVID-19) patients or with colleagues were associated with infection with severe acute respiratory syndrome coronavirus 2, whereas working in a COVID-dedicated unit and having children kept in childcare facilities were not.

SARS-COV-2 IgG antibody response in pregnant women at delivery.

BACKGROUND: The prevalence of COVID-19 infection during pregnancy is not known. COVIPREG is a prospective French multicenter study to assess the seroprevalence at the time of delivery and the maternal and neonatal impact of COVID-19 infection during pregnancy. In order to study factors associated with poor outcomes after COVID-19 Infection during pregnancy and adapt the sample size of the study, a preliminary assessment of the prevalence of SARS-CoV-2 IgG was planned after 500 inclusions in a one perinatal center of Paris area. OBJECTIVES: To assess the prevalence of SARS-CoV-2 IgG antibody response in pregnant women at the time of delivery during the COVID-19 pandemia. STUDY DESIGN: A prospective observational study at Cochin hospital (Level III maternity). Patients admitted for delivery were offered to participate to the study. Each patient participating to the study was tested for anti-SARS-CoV-2-IgG antibodies using a commercially available ELISA. RESULTS: Among the 529 patients included in the COVIPREG study between April 29 and June 26, 529 were assessed for SARS-CoV-2 IgG antibody response and 25 had a positive test, ie 4.7 % with a confidence interval at 95 % [3.0 %-6.9 %]). CONCLUSIONS: Four months after the beginning of the infection in Paris, the seroprevalence of SARS-CoV-2 IgG in pregnant women at the time of delivery is low. Studies evaluating the impact of COVID-19 infection during pregnancy should take this information in account in order to adapt the sample size.

Comparing Dynamics and Determinants of Severe Acute Respiratory Syndrome Coronavirus 2 Transmissions Among Healthcare Workers of Adult and Pediatric Settings in Central Paris.

BACKGROUND: Healthcare workers (HCWs) have paid a heavy toll during the coronavirus disease 2019 (COVID-19) outbreak. Routes of transmission remain to be fully understood. METHODS: This prospective study compared a 1500-bed adult and 600-bed pediatric setting of a tertiary-care university hospital located in central Paris. From 24 February until 10 April 2020, all symptomatic HCWs were screened for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on a nasopharyngeal swab. HCWs screened positive were questioned on their profession, symptoms, and occupational and nonoccupational exposures to SARS-CoV-2. RESULTS: Among 1344 HCWs tested, 373 were positive (28%) and 336 (90%) corresponding questionnaires were completed. Three hospitalizations and no deaths were reported. Most HCWs (70%) had patient-facing occupational activities (22% in COVID-19 dedicated units). The total number of HCW cases peaked on 23 March, then decreased slowly, concomitantly with a continuous increase of compliance to preventive measures (including universal medical masking and personal protective equipment [PPE] for direct care to COVID-19 patients). Attack rates were of 3.2% and 2.3% in the adult and pediatric settings, respectively (P = .0022). In the adult setting, HCWs more frequently reported exposure to COVID-19 patients without PPE (25% vs 15%, P = .046). Report of contacts with children attending out-of-home care facilities dramatically decreased over the study period. CONCLUSIONS: Universal masking, reinforcement of hand hygiene, and PPE with medical masks for patients' care allowed protection of HCWs and containment of the outbreak. Residual transmissions were related to persistent exposures with undiagnosed patients or colleagues and not to contacts with children attending out-of-home care facilities.

Arterial abnormalities identified in kidneys transplanted into children during the COVID-19 pandemic.

Graft artery stenosis can have a significant short- and long-term negative impact on renal graft function. From the beginning of the COVID-19 pandemic, we noticed an unusual number of graft arterial anomalies following kidney transplant (KTx) in children. Nine children received a KTx at our center between February and July 2020, eight boys and one girl, of median age of 10 years. Seven presented Doppler features suggesting arterial stenosis, with an unusual extensive pattern. For comparison, over the previous 5-year period, persistent spectral Doppler arterial anomalies (focal anastomotic stenoses) following KTx were seen in 5% of children at our center. We retrospectively evidenced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in five of seven children with arterial stenosis. The remaining two patients had received a graft from a deceased adolescent donor with a positive serology at D0. These data led us to suspect immune postviral graft vasculitis, triggered by SARS-CoV-2. Because the diagnosis of COVID-19 is challenging in children, we recommend pretransplant monitoring of graft recipients and their parents by monthly RT-PCR and serology. We suggest balancing the risk of postviral graft vasculitis against the risk of prolonged dialysis when considering transplantation in a child during the pandemic.