Enhancing SARS-CoV-2 Surveillance through Regular Genomic Sequencing in Spain: The RELECOV Network.

Millions of SARS-CoV-2 whole genome sequences have been generated to date. However, good quality data and adequate surveillance systems are required to contribute to meaningful surveillance in public health. In this context, the network of Spanish laboratories for coronavirus (RELECOV) was created with the main goal of promoting actions to speed up the detection, analyses, and evaluation of SARS-CoV-2 at a national level, partially structured and financed by an ECDC-HERA-Incubator action (ECDC/GRANT/2021/024). A SARS-CoV-2 sequencing quality control assessment (QCA) was developed to evaluate the network's technical capacity. QCA full panel results showed a lower hit rate for lineage assignment compared to that obtained for variants. Genomic data comprising 48,578 viral genomes were studied and evaluated to monitor SARS-CoV-2. The developed network actions showed a 36% increase in sharing viral sequences. In addition, analysis of lineage/sublineage-defining mutations to track the virus showed characteristic mutation profiles for the Delta and Omicron variants. Further, phylogenetic analyses strongly correlated with different variant clusters, obtaining a robust reference tree. The RELECOV network has made it possible to improve and enhance the genomic surveillance of SARS-CoV-2 in Spain. It has provided and evaluated genomic tools for viral genome monitoring and characterization that make it possible to increase knowledge efficiently and quickly, promoting the genomic surveillance of SARS-CoV-2 in Spain.

Frequent Placental SARS-CoV-2 in Patients with COVID-19-Associated Hypertensive Disorders of Pregnancy.

INTRODUCTION: Studies described an increased frequency of hypertensive disorders of pregnancy (HDP) after a COVID-19 episode. There is limited evidence about SARS-CoV-2 viral load in placenta. This study aimed to investigate the relationship between SARS-CoV-2 viral load in the placenta and clinical development of HDP after COVID-19 throughout different periods of gestation. METHODS: This is a case-control study in women with and without gestational hypertensive disorders after SARS-CoV-2 infection diagnosed by RT-PCR during pregnancy. Patients were matched by gestational age at the moment of COVID-19 diagnosis. We performed an analysis of SARS-CoV-2 RNA levels in placenta. RESULTS: A total of 28 women were enrolled. Sixteen patients were diagnosed with COVID-19 during the third trimester and the remaining 12 patients in the other trimesters. Ten placentas (35.7%) were positive for SARS-CoV-2, 9 of them (9/14, 64.3%) belonged to the HDP group versus 1 (1/14, 7.2%) in the control group (p = 0.009). Those cases with the highest loads of viral RNA developed severe preeclampsia (PE). CONCLUSION: Among women diagnosed with COVID-19 during pregnancy, the presence of SARS-CoV-2 in the placenta was more frequent among women suffering from PE or gestational hypertension. Furthermore, the most severe cases of HDP were associated with high placental viral load, not necessarily associated with a positive nasopharyngeal RT-PCR at delivery. Our data suggest that SARS-CoV-2 infection during pregnancy could trigger gestational hypertensive disorders through persistent placental infection and resulting placental damage.

No antibody response in cutaneous manifestations associated with COVID-19: An observational study of 64 cases with microbiological and clinical characterization.

BACKGROUND: The microbiological diagnosis of skin lesions related to COVID-19 is not well known. OBJECTIVE: Perform a microbiological diagnosis in COVID19-related cutaneous manifestations. METHODS: A cross-sectional study was performed with 64 patients with cutaneous manifestations associated with COVID-19 who underwent serological and nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2. RESULTS: Out of the 64 patients, 6 patients had positive RT-PCR, with all of them developing SARS-CoV-2 IgG and 4 of them had positive IgM + IgA. Of the 58 patients with negative RT-PCR, 8 cases had positive IgM + IgA and only one of them had IgG seroconversion. Therefore, the infection was demonstrated in 7 cases (10.9%) and was doubtful in 7 other cases (10.9%) who presented negative RT-PCR and presence of IgA + IgM without subsequent seroconversion of IgG. Fifty patients (78.1%) had negative serological tests. The most frequent cutaneous pattern was pseudo-chilblain (48.4%) followed by maculo-papular pattern (26.6%), urticarial lesions (10.9%), vesicular eruptions (6.3%) and livedoid pattern (4.7%). The maculo-papular pattern showed the highest positivity in RT-PCR (3 cases; 17.6%) and serologies (4 cases; 23.5%). Skin lesions developed after the systemic symptoms in most patients (19 cases; 61.3%). CONCLUSIONS: Microbiological confirmation tests may not be an effective diagnostic technique for COVID-related cutaneous manifestations or that attributed lesions are not related to COVID-19. Confounding factors such as adverse drug reaction, serological cross-reactions with other viruses, the low production of antibodies in asymptomatic or mild forms of COVID-19 or its rapid disappearance, increase diagnostic uncertainty.

Antibody response in patients admitted to the hospital with suspected SARS-CoV-2 infection: results from a multicenter study across Spain.

AIM: To evaluate the serological response against SARS-CoV-2 in a multicenter study representative of the Spanish COVID pandemic. METHODS: IgG and IgM + IgA responses were measured on 1466 samples from 1236 Spanish COVID-19 patients admitted to the hospital, two commercial ELISA kits (Vircell SL, Spain) based on the detection of antibodies against the viral spike protein and nucleoprotein, were used. RESULTS: Approximately half of the patients presented antibodies (56.8% were IgM + IgA positive and 43.0% were IgG positive) as soon as 2 days after the first positive PCR result. Serological test positivity increased with time from the PCR test, and 10 days after the first PCR result, 91.5% and 88.0% of the patients presented IgM + IgA and IgG antibodies, respectively. CONCLUSION: The high values of sensitivity attained in the present study from a relatively early period of time after hospitalization support the use of the evaluated serological assays as supplementary diagnostic tests for the clinical management of COVID-19.