Plasma UCHL1, GFAP, Tau, and NfL Are Not Different in Young Healthy Persons With Mild COVID-19 Symptoms Early in the Pandemic: A Pilot Study.

Elevated levels of brain injury biomarkers have been found primarily in middle-aged or older persons experiencing moderate-to-severe COVID-19 symptoms. However, there is little research in young adults, and there is concern that COVID-19 causes brain injury even in the absence of moderate-to-severe symptoms. Therefore, the purpose of our study was to investigate whether neurofilament light (NfL), glial fibrillary acidic protein (GFAP), tau, or ubiquitin carboxyl-terminal esterase L1 (UCHL1) are elevated in the plasma of young adults with mild COVID-19 symptoms. Twelve participants diagnosed with COVID-19 had plasma collected 1, 2, 3, and 4 months after diagnosis to determine whether NfL, GFAP, tau, and UCHL1 concentrations increased over time or whether plasma concentrations were elevated compared with COVID-19-naïve participants. We also compared plasma NfL, GFAP, tau, and UCHL1 concentrations between sexes. Our results showed no difference between NfL, GFAP, tau, and UCHL1 concentrations in COVID-19-naïve participants and COVID-19-positive participants at any of the four time points (p = 0.771). Within the COVID-19-positive participants, UCHL1 levels were higher at month 3 after diagnosis compared to month 1 or month 2 (p = 0.027). Between sexes, females were found to have higher UCHL1 (p = 0.003) and NfL (p = 0.037) plasma concentrations compared to males, whereas males had higher plasma tau concentrations than females (p = 0.024). Based on our data, it appears that mild COVID-19 in young adults does not increase plasma NfL, GFAP, tau, or UCHL1.

Differential regulatory T cell signature after recovery from mild COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by a range of symptoms in which host immune response have been associated with disease progression. However, the putative role of regulatory T cells (Tregs) in determining COVID-19 outcomes has not been thoroughly investigated. Here, we compared peripheral Tregs between volunteers not previously infected with SARS-CoV-2 (healthy control [HC]) and volunteers who recovered from mild (Mild Recovered) and severe (Severe Recovered) COVID-19. Peripheral blood mononuclear cells (PBMC) were stimulated with SARS-CoV-2 synthetic peptides (Pool Spike CoV-2 and Pool CoV-2) or staphylococcal enterotoxin B (SEB). Results of a multicolor flow cytometric assay showed higher Treg frequency and expression of IL-10, IL-17, perforin, granzyme B, PD-1, and CD39/CD73 co-expression in Treg among the PBMC from the Mild Recovered group than in the Severe Recovered or HC groups for certain SARS-CoV-2 related stimulus. Moreover, Mild Recovered unstimulated samples presented a higher Tregs frequency and expression of IL-10 and granzyme B than did that of HC. Compared with Pool CoV-2 stimuli, Pool Spike CoV-2 reduced IL-10 expression and improved PD-1 expression in Tregs from volunteers in the Mild Recovered group. Interestingly, Pool Spike CoV-2 elicited a decrease in Treg IL-17+ frequency in the Severe Recovered group. In HC, the expression of latency-associated peptide (LAP) and cytotoxic granule co-expression by Tregs was higher in Pool CoV-2 stimulated samples. While Pool Spike CoV-2 stimulation reduced the frequency of IL-10+ and CTLA-4+ Tregs in PBMC from volunteers in the Mild Recovered group who had not experienced certain symptoms, higher levels of perforin and perforin+granzyme B+ co-expression by Tregs were found in the Mild Recovered group in volunteers who had experienced dyspnea. Finally, we found differential expression of CD39 and CD73 among volunteers in the Mild Recovered group between those who had and had not experienced musculoskeletal pain. Collectively, our study suggests that changes in the immunosuppressive repertoire of Tregs can influence the development of a distinct COVID-19 clinical profile, revealing that a possible modulation of Tregs exists among volunteers of the Mild Recovered group between those who did and did not develop certain symptoms, leading to mild disease.

Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response up to 10 Months.

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to considerable morbidity/mortality worldwide, but most infections, especially among children, have a mild course. However, it remains largely unknown whether infected children develop cellular immune memory. Methods: To determine whether a memory T cell response is being developed, we performed a longitudinal assessment of the SARS-CoV-2-specific T cell response by IFN-γ ELISPOT and activation marker analyses of peripheral blood samples from unvaccinated children and adults with mild-to-moderate COVID-19. Results: Upon stimulation of PBMCs with heat-inactivated SARS-CoV-2 or overlapping peptides of spike (S-SARS-CoV-2) and nucleocapsid proteins, we found S-SARS-CoV-2-specific IFN-γ T cell responses in infected children (83%) and adults (100%) that were absent in unexposed controls. Frequencies of SARS-CoV-2-specific T cells were higher in infected adults, especially several cases with moderate symptoms, compared to infected children. The S-SARS-CoV-2 IFN-γ T cell response correlated with S1-SARS-CoV-2-specific serum antibody concentrations. Predominantly, effector memory CD4+ T cells of a Th1 phenotype were activated upon exposure to SARS-CoV-2 antigens. Frequencies of SARS-CoV-2-specific T cells were significantly reduced at 10 months after symptom onset, while S1-SARS-CoV-2-specific IgG concentrations were still detectable in 90% of all children and adults. Conclusions: Our data indicate that an antigen-specific T cell and antibody response is developed after mild SARS-CoV-2 infection in children and adults. It remains to be elucidated to what extent this SARS-CoV-2-specific response can contribute to an effective recall response after reinfection.

Corrigendum: Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response Up to 10 Months.

[This corrects the article DOI: 10.3389/fimmu.2022.817876.].

Manifestations and risk factors of post COVID syndrome among COVID-19 patients presented with minimal symptoms - A study from Kerala, India.

BACKGROUND: COVID 19 is associated with the development of post COVID syndrome usually manifested as fatigue, anxiety, joint pain, headache, chest pain, dementia, depression, and dyspnea. Documented evidence of post COVID syndrome among patients with asymptomatic or mild infections, especially from India is less. METHODOLOGY: A community based prospective cohort study was conducted among 154 patients admitted in CFLTCs of coastal Thiruvananthapuram, Kerala during May-August 2020. They were enrolled at the time of their admission to CFLTCs and were followed up for three months after discharge. The discharged patients were followed up at regular intervals of three weeks and three months by telephonic interview using a structured proforma. RESULTS: Out of the 154 patients followed up, 57 (37%) were men and 97 (63%) were women. The mean (SD) age of study participants was 31.49 (18.4) years. At least one symptom was present in 120 (78.0%) patients at the time of admission. Cough (29, 18.8%), fever (26, 16.8%), headache (25, 16.2%), rhinitis (23,14.9%) and sore throat (18, 11.7%) were the major symptoms reported at the time of admission. At the end of three weeks, 11 (7.1%) patients and at the end of three months 18 (11.7%) patients reported to have symptoms. Fatigue (5.8%), headache (5.8%) myalgia (3.2%) joint pain (2.5%) and exertional dyspnea (2.5%) were the predominant symptoms. Presence of fatigue, cough and breathlessness at the time of admission, and presence of another COVID positive family member were significantly associated with the appearance of post COVID symptoms. CONCLUSION: Post COVID syndrome is not uncommon in COVID 19 patients with minimal symptoms. Understanding long term consequences of COVID 19 is as important as management of acute COVID 19 due to its multisystem involvement and its implications on health and well-being.

Review on Home Care Recommendations for Patients with Suspected COVID-19 Presenting with Mild Symptoms

Caring for COVID-19 patients at home is a global challenge. This study aimed to review recommendations put forward on home care for patients with suspected COVID-19 presenting with mild clinical features. This is a review of the scientific literature covering COVID-19 and home care from the medical electronic databases such as PubMed, ProQuest, Google Scholar, and CINAHL. The electronic databases were searched from the beginning of 2019 to the end of August 2020. The search terms included home care, COVID-19, coronavirus disease 2019, caring, and nursing care. Articles were included if they reported on aspects of home care for managing patients with mild clinical features of COVID-19. Articles were excluded if they reported on management within healthcare facilities, were about therapeutic management not possible in home care, and non-study type articles. Reference lists of retrieved journals were also reviewed. There was a total of 1,970 identified articles;950 studies were duplicates and were removed, after which 500 titles and s remained for review. Review of the title and s found 60 articles which met the inclusion criteria. After analysis of the full text articles, 12 articles were included in this study. The main areas covering home care can be summarized as home-based quarantine, management of contacts, early diagnosis at home, control of clinical features (i.e. fever and cough), appropriate nutrition and adequate fluid intake, establishment of a monitoring center, psychological support, and telemedicine. The use of home quarantine for people with mild clinical features of COVID-19 is possible with support services and will assist in reducing the demand on hospitals.

Influence of isolation measures for patients with mild symptoms on the spread of COVID-19.

During the transmission of COVID-19, the hospital isolation of patients with mild symptoms has been a concern. In this paper, we use a differential equation model to describe the propagation of COVID-19, and discuss the effects of intensity of hospital isolation and moment of taking measures on development of the epidemic. The results show that isolation measures can significantly reduce the epidemic final size and the number of dead, and the greater the intensity of measures, the better, but duration of the epidemic will be prolonged. Whenever isolation measures are taken, the epidemic final size and the number of dead can be reduced. In early stage of the epidemic, taking measures one day later has little impact, but after a certain period, if taking measures one day later, the epidemic final size and the number of dead increase sharply. Taking measures as early as possible makes the maximum number of patients appear later, which is conducive to expanding medical bed resources and reducing the pressure on medical resource demand. As long as possible, high-intensity isolation measures should be taken in time for patients with mild symptoms.

COVID-19: Clinical aspects and therapeutics responses.

COVID-19 has created havoc in the world by causing thousands of demises in a short period of time. Up till now, several attempts have been made for potential therapeutics against SARS-COV2. In this retrospective, single-center study, we extracted data from 122 COVID-19, RT-PCR confirmed patients. who were treated with a new treatment strategy of lianhuaqingwen with Arbidol Hydrochloride. The patients were either asymptomatic or had mild symptoms for COVID-19 disease. Of 122 patients 21 (17.21%) patients developed severe conditions of COVID-19, while total 111 (90.9%) experienced mild symptoms such as fever in 93 (76.22%) patients, cough in 23 (20.17%) and muscle pain were observed in total 8 (7%) patients. Furthermore our newly applied drugs combination (Lianhuaqingwen and Arbidol Hydrochloride) showed therapeutic effects in 5-7 days in patients with mild symptoms with 98% recovery rate. These results indicate that COVID-19 patients with mild symptoms can be treated with Lianhuaqingwen and Arbidol Hydrochloride. However, extensive clinical investigations are required to confirm the effectiveness of these drugs.