High titers of infectious SARS-CoV-2 in corpses of patients with COVID-19.

OBJECTIVES: The prolonged presence of infectious SARS-CoV-2 in deceased patients with COVID-19 has been reported. However, infectious virus titers have not been determined. Such information is important for public health, death investigation, and handling corpses. The aim of this study was to assess the level of SARS-CoV-2 infectivity in the corpses of patients with COVID-19. METHODS: We collected 11 nasopharyngeal swabs and 19 lung tissue specimens from 11 autopsy cases with COVID-19 in 2021. We then investigated the viral genomic copy number by real-time reverse transcription-polymerase chain reaction and infectious titers by cell culture and virus isolation. RESULTS: Infectious virus was present in six of 11 (55%) cases, four of 11 (36%) nasopharyngeal swabs, and nine of 19 (47%) lung specimens. The virus titers ranged from 6.00E + 01 plaque-forming units/ml to 2.09E + 06 plaque-forming units/g. In all cases in which an infectious virus was found, the time from death to discovery was within 1 day and the longest postmortem interval was 13 days. CONCLUSION: The corpses of patients with COVID-19 may have high titers of infectious virus after a long postmortem interval (up to 13 days). Therefore, appropriate infection control measures must be taken when handling corpses.

COVID-19-associated myocardial injury: A case report.

Coronavirus disease 2019 (COVID-19) is often accompanied by pneumonia and can be fatal. We report a case of COVID-19-associated myocardial injury mimicking fulminant myocarditis. Endomyocardial biopsy revealed numerous von Willebrand factor-rich microthrombi with small myocardial necrotic areas, complement deposits in small vessels/microthrombi, and macrophage-predominant interstitial infiltration. These findings, distinct from those of typical lymphocytic myocarditis, show diffuse endothelial injury, complement activation, and activated macrophages as characteristic features of COVID-19-associated pathogenesis. Dysregulated serum cytokine profiles predicting severe/critical COVID-19-associated myocardial injury were also determined. This case emphasizes the occurrence of fatal cardiac manifestation with microthrombotic injury in the early stage of COVID-19.

Non-Omicron breakthrough infection with higher viral load and longer vaccination-infection interval improves SARS-CoV-2 BA.4/5 neutralization.

The immune responses to SARS-CoV-2 variants in COVID-19 cases are influenced by various factors including pre-existing immunity via vaccination and prior infection. Elucidating the drivers for upgrading neutralizing activity to SARS-CoV-2 in COVID-19 cases with pre-existing immunity will aid in improving COVID-19 booster vaccines with enhanced cross-protection against antigenically distinct variants, including the Omicron sub-lineage BA.4/5. This study revealed that the magnitude and breadth of neutralization activity to SARS-CoV-2 variants after breakthrough infections are determined primarily by upper respiratory viral load and vaccination-infection time interval. Extensive neutralizing breadth, covering even the most antigenically distant BA.4/5, was observed in cases with higher viral load and longer time intervals. Antigenic cartography depicted a critical role of the time interval in expanding the breadth of neutralization to SARS-CoV-2 variants. Our results illustrate the importance of dosing interval optimization as well as antigen design in developing variant-proof booster vaccines.

SARS-CoV-2 is localized in cardiomyocytes: a postmortem biopsy case.

A 72-year-old patient was admitted to the intensive care unit due to acute respiratory distress syndrome caused by COVID-19. On day 20, the patient experienced shock. The electrocardiogram showed ST segment elevation in leads V3-V6 and severe left ventricular dysfunction with an ejection fraction of 35%-40%. The left ventricle showed basal hypokinesis and apical akinesis, while the creatine kinase level was normal, indicating Takotsubo cardiomyopathy. On day 24, the patient died of multiple organ failure. In post-mortem biopsy, SARS-CoV-2 antigen was detected in cardiomyocytes by immunostaining. Moreover, SARS-CoV-2 RNA was detected in heart tissue. We need to further analyse the direct link between SARS-CoV-2 and cardiomyocytes.

An Autopsy Report of a Case with Cerebral Infarction Complicated by Coronavirus Disease 2019 Infection.

We herein report a case of cerebral infarct in a patient with coronavirus disease 2019 (COVID-19) infection who died of aspiration pneumonia. The postmortem examination of the brain revealed embolic infarct with negative findings on quantitative reverse transcription polymerase chain reaction (qRT-PCR) as well as immunohistochemistry to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The systemic examination only revealed low copy numbers of SARS-CoV-2 in the bronchus. This is the first and so far only autopsy case of COVID-19 infection with pathologic and virologic findings of the postmortem brain in Japan.

An autopsy case of fulminant myocarditis after severe acute respiratory syndrome coronavirus 2 vaccine inoculation.

A 61-year-old woman without significant medical history developed fever 3 days after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and went into shock the next day. She was negative for SARS-CoV-2 mRNA in real-time polymerase chain reaction (PCR). Finally, she died 10 days after vaccination. At autopsy, the heart showed moderate dilatation of both ventricles, and the myocardium showed an uneven color change and decreased elasticity. Histologically, severe myocarditis with extensive myocytolysis was observed. The myocarditis showed severe inflammatory cell infiltration with T-lymphocyte and macrophage predominance, and in addition to the inflammatory cells described above, vast nuclear dust accompanying neutrophilic infiltration was observed. In the bone marrow and lymph nodes, hemophagocytosis was observed. In postmortem examination, nucleic acids of any cardiotropic viruses including SARS-CoV-2 were not detected using multivirus real-time PCR system. We discussed the relationship between the possible immune reaction after vaccination and the myocarditis observed in this case from immunopathological viewpoints. This mRNA vaccine is the first applied nucleic acid vaccine for humans, and its mechanism of efficacy and immune acquisition remain unclear. We hope the accumulation of more detailed analyses of the similar cases to reveal the mechanism of this kind of adverse reaction.

Microthrombosis as a cause of fulminant myocarditis-like presentation with COVID-19 proven by endomyocardial biopsy.

Myocardial injury has been reported as a complication of COVID-19. Although several mechanisms have been proposed as its cause, they are mostly based on autopsy studies, We report a 49-year-old male with COVID-19-associated myocardial injury presented like fulminant myocarditis. We performed endomyocardial biopsy on day 2 and we confirmed the presence of microthrombosis histologically. He died on day 5 due to cardiogenic shock.

Vaccination-infection interval determines cross-neutralization potency to SARS-CoV-2 Omicron after breakthrough infection by other variants.

Background: The immune profile against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has dramatically diversified due to a complex combination of exposure to vaccines and infection by various lineages/variants, likely generating a heterogeneity in protective immunity in a given population. To further complicate this, the Omicron variant, with numerous spike mutations, has emerged. These circumstances have created the need to assess the potential of immune evasion by Omicron in individuals with various immune histories. Methods: The neutralization susceptibility of the variants, including Omicron and their ancestors, was comparably assessed using a panel of plasma/serum derived from individuals with divergent immune histories. Blood samples were collected from either mRNA vaccinees or from those who suffered from breakthrough infections of Alpha/Delta with multiple time intervals following vaccination. Findings: Omicron was highly resistant to neutralization in fully vaccinated individuals without a history of breakthrough infections. In contrast, robust cross-neutralization against Omicron was induced in vaccinees that experienced breakthrough infections. The time interval between vaccination and infection, rather than the variant types of infection, was significantly correlated with the magnitude and potency of Omicron-neutralizing antibodies. Conclusions: Immune histories with breakthrough infections can overcome the resistance to infection by Omicron, with the vaccination-infection interval being the key determinant of the magnitude and breadth of neutralization. The diverse exposure history in each individual warrants a tailored and cautious approach to understanding population immunity against Omicron and future variants. Funding: This study was supported by grants from the Japan Agency for Medical Research and Development (AMED).

Pathologic and Neuropathologic Study of a Case of COVID-19.

A 68-year-old woman with a history of schizophrenia developed coronavirus disease (COVID)-19 and was transferred to our hospital. Despite treatment, she died of respiratory failure 16 days after the onset. At the time of autopsy, polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using swabs from the nasopharynx and the lung was positive; however, the cerebrospinal fluid was negative. An autopsy showed diffuse alveolar damage and recent multiple cerebral infarcts. Acute splenitis was observed with thrombi adhering to the vascular endothelium in areas of severe neutrophilic infiltration. Immunohistochemistry using an antibody against the SARS-CoV-2 nucleocapsid showed immunoreactivity along the hyaline membrane of the lung; however, the antibody showed no immunoreactivity in the medulla, the thalamus, the frontal lobe, and the pituitary. Future pathologic studies should clarify the mechanisms involved in a variety of clinical and pathological changes related to COVID-19.

A case of varicella zoster virus meningitis following BNT162b2 mRNA COVID-19 vaccination in an immunocompetent patient.

We report a case of varicella zoster virus (VZV) meningitis following BNT162b2 mRNA COVID-19 vaccination in an immunocompetent patient. A final diagnosis was made based on identification of VZV via positive polymerase chain reaction of cerebrospinal fluid along with characteristic symptoms such as fever, headache, and stiff neck. This phenomenon has been reported elsewhere; this is the 13th such case reported worldwide and the 7th case in immunocompetent patients, indicating the need for careful monitoring after COVID-19 vaccines.

Subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques.

SARS-CoV-2 infection presents clinical manifestations ranging from asymptomatic to fatal respiratory failure. Despite the induction of functional SARS-CoV-2-specific CD8+ T-cell responses in convalescent individuals, the role of virus-specific CD8+ T-cell responses in the control of SARS-CoV-2 replication remains unknown. In the present study, we show that subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques. Eight macaques were intranasally inoculated with 105 or 106 TCID50 of SARS-CoV-2, and three of the eight macaques were treated with a monoclonal anti-CD8 antibody on days 5 and 7 post-infection. In these three macaques, CD8+ T cells were undetectable on day 7 and thereafter, while virus-specific CD8+ T-cell responses were induced in the remaining five untreated animals. Viral RNA was detected in nasopharyngeal swabs for 10-17 days post-infection in all macaques, and the kinetics of viral RNA levels in pharyngeal swabs and plasma neutralizing antibody titers were comparable between the anti-CD8 antibody treated and untreated animals. SARS-CoV-2 RNA was detected in the pharyngeal mucosa and/or retropharyngeal lymph node obtained at necropsy on day 21 in two of the untreated group but undetectable in all macaques treated with anti-CD8 antibody. CD8+ T-cell responses may contribute to viral control in SARS-CoV-2 infection, but our results indicate possible containment of subacute viral replication in the absence of CD8+ T cells, implying that CD8+ T-cell dysfunction may not solely lead to viral control failure.

Coronavirus disease (COVID-19) associated delayed-onset fulminant myocarditis in patient with a history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

A healthy 35-year-old man was admitted to a rural hospital with coronavirus disease (COVID-19). During 14 days of hospitalization, he had no symptoms and was not given supplemental oxygen. About 3 weeks after discharge, he was re-admitted to the same hospital with new-onset continuous fever and general weakness. At the time of his second admission, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RT-PCR was performed on a retro-nasal swab and the result was negative. Four days after admission, the patient was transferred to our intensive care unit (ICU) following deterioration of his respiratory and haemodynamic conditions, where he received mechanical ventilation, intra-aortic balloon pumping, and veno-arterial extracorporeal membrane oxygenation. A nasopharyngeal swab was obtained again at ICU admission, but RT-PCR was negative for SARS-CoV-2. All antibody titres measured against other viruses were low. Blood cultures were negative, and no bacteria were observed in sputum samples. However, SARS-CoV-2 RNA was detected by RT-PCR from sections obtained by myocardial biopsy. The patient's final diagnosis was delayed-onset SARS-CoV-2-induced fulminant myocarditis (FM). We strongly suggested that one of the proposed mechanisms of COVID-19-related myocardial injury will be the direct invasion of SARS-CoV-2 into cardiomyocytes even if delayed-onset. And this is the first case of delayed-onset FM in which diagnosis of active myocarditis was proven by pathological examination following endomyocardial biopsy and SARS-CoV-2 was detected in the myocardium by RT-PCR.

SARS-CoV-2 Leakage From the Gas Outlet Port During Extracorporeal Membrane Oxygenation for COVID-19.

Patients with the coronavirus disease 2019 (COVID-19) sometimes develop refractory respiratory failure and may require venovenous extracorporeal membrane oxygenation (VV-ECMO). It is known that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is sometimes present in the blood of COVID-19 patients. VV-ECMO is often used for several weeks, and plasma leaks can occur, albeit rarely. Hence, in terms of infection control, a concern is that SARS-CoV-2 may leak from the gas outlet port of the oxygenator during ECMO support of critically ill COVID-19 patients. The aim of this study was to clarify whether SARS-CoV-2 leaks from the oxygenator during ECMO support. Five patients with critical COVID-19 pneumonia were placed on VV-ECMO. Silicone-coated polypropylene membrane oxygenators were used in the ECMO circuits for these patients. SARS-CoV-2 ribonucleic acid (RNA) was measured by quantitative reverse transcription polymerase chain reaction in serum and at the gas outlet port of the ECMO circuit at the time of circuit replacement or liberation from ECMO. SARS-CoV-2 RNA was detected in the gas outlet port of the ECMO circuit for three of the five patients. None of the medical staff involved in the care of these five patients has been infected with COVID-19. In conclusion, SARS-CoV-2 could leak to the gas outlet port of the ECMO circuit through silicone-coated polypropylene membranes during ECMO support of critically ill COVID-19 patients.

Lung Pathology of Mutually Exclusive Co-infection with SARS-CoV-2 and Streptococcus pneumoniae.

Postmortem lung pathology of a patient in Japan with severe acute respiratory syndrome coronavirus 2 infection showed diffuse alveolar damage as well as bronchopneumonia caused by Streptococcus pneumoniae infection. The distribution of each pathogen and the accompanying histopathology suggested the infections progressed in a mutually exclusive manner within the lung, resulting in fatal respiratory failure.

Successful Recovery from COVID-19-associated Acute Respiratory Failure with Polymyxin B-immobilized Fiber Column-direct Hemoperfusion.

An 83-year-old man was hospitalized for coronavirus disease 2019 (COVID-19) after a 10-day history of a persistent fever. Chest computed tomography showed extensive non-segmental ground glass opacity. Despite the initiation of lopinavir and ritonavir, respiratory failure progressed. Two days of polymyxin B-immobilized fiber column-direct hemoperfusion (PMX-DHP) with adjunctive corticosteroid prevented his respiratory condition from worsening. For rapidly progressive COVID-19 cases, the early use of PMX-DHP may avoid the need for mechanical ventilation by suppressing local inflammation of the lung.

Detection of SARS-CoV-2 in Hemodialysis Effluent of Patient with COVID-19 Pneumonia, Japan.

We report detection of severe acute respiratory syndrome coronavirus 2 RNA in hemodialysis effluent from a patient in Japan with coronavirus disease and prolonged inflammation. Healthcare workers should observe strict standard and contact precautions and use appropriate personal protective equipment when handling hemodialysis circuitry from patients with diagnosed coronavirus disease.

Development of Genetic Diagnostic Methods for Detection for Novel Coronavirus 2019(nCoV-2019) in Japan.

During the emergence of novel coronavirus 2019 (nCoV) outbreak in Wuhan city, China at the end of 2019, there was movement of many airline travelers between Wuhan and Japan, suggesting that the Japanese population was at high risk of infection by the virus. Hence, we urgently developed diagnostic systems for detection of 2019 nCoV. Two nested RT-PCR and two real-time RT-PCR assays were adapted for use in Japan. As of February 8, 2020, these assays have successfully detected 25 positive cases of infection in Japan.