ALTERED FEATURES of B and T CELL RESPONSES to BNT162 VACCINE in HEMODIALYSIS PATIENTS

Background: People receiving hemodialysis (HD) are highly vulnerable to SARS-CoV-2 infection and develop lower antibody responses to SARS-CoV-2 mRNA vaccines. However, the underlying immune defects are poorly understood. We compared immune responses of 27 HD patients with 22 health care workers (HCW) before and up to 4 months after 2 doses of BNT162 SARS-CoV-2 vaccination. All participants were confirmed to be SARS-CoV-2 naïve. Methods: We profiled B cells, CD4 T cells, CD8 T cells and humoral responses and examined associations between these arms of immunity. We used high-parameter flow cytometry to study: i) receptor binding domain (RBD)-specific B cells;ii) the phenotype of Spike (S)-specific CD4 and CD8 T cells identified by an activation-induced marker (AIM) assay;iii) effector functions of S-specific CD4 and CD8 T cells by intracellular staining (ICS). We measured humoral responses by ELISA RBD. Results: In each cohort, two vaccine doses enhanced RBD-specific B cell responses, with a significantly greater increase after the second dose (V2 than after the first dose (V1). Their magnitude was significantly lower in HD than in HCW at V1 (p=0.002) and V2 (p=0.002), which was consistent with the detection of lower anti-RBD IgG antibody levels at the same time points (V1: p<0.001;V2: p<0.001). The subsequent rates of B cell decline were similar in HD and HCW. As CD4 help is critical for B cell and CD8 T cell immunity, we compared Spike (S)-specific T cells responses between cohorts. While we observed no significant quantitative difference in the magnitude of vaccine-specific CD4 T cells between HD and HCW at V2, phenotypic and functional Thelper profiles differed significantly. The frequency of vaccine-specific CXCR3+ Th1 CD4 T cells was significantly increased in HD compared to HCW (p=0.008), and TNFα+ CD4 T cell responses were elevated in HD (p=0.01). In contrast to CD4 T cells, S-specific CD8 T cell responses were quantitatively reduced in HD compared to HCW after each dose (V1: p<0.001;V2: p<0.001). Conclusion: People on HD develop poor B cell and CD8 T cell responses after SARS-CoV-2 mRNA vaccination. These defects are associated with a skewed differentiation of vaccine-specific CD4 T cells toward CXCR3+ and TNFα+ Th1-like profiles, and probable altered crosstalk between Thelper and B cells. Further study is needed to determine if impaired B and T cell vaccine immunity in addition to defective antibody responses increases vulnerability of HD patients to breakthrough COVID-19 infection.

Dengue- COVID 19 co-infection: An uphill battle

Background: COVID-19 and dengue infection both are caused by single-stranded RNA viruses of the families' coronaviridae and flaviviridae respectively. Both diseases share various clinical and laboratory parameters, making them difficult to distinguish from one another. In these times of covid-19 where dengue is already a public health concern, this co-infection poses great threat to already burdened healthcare system. Case Study: So, here we report a case of 76 year old male with complaints of high grade fever and dyspnea for 2 days diagnosed with COVID-19 who was simultaneously diagnosed with dengue infection and later died of ARDS and sepsis delineating the rarity and severity of this coinfection. Discussion: In the tropical counties, there is an emerging threat of dengue-covid co-infection. They have overlapping clinical presentations, also share several laboratory parameters like elevated liver enzymes, leukopenia and thrombocytopenia. Aggressive fluid resuscitation has a key role in dengue which may worsen oxygenation in COVID-19 patients. Also, the use of LMWH in COVID-19 settings can have a devastating effect in the setting of thrombocytopenia in case of dual infection. Conclusion: As we wait for more data, it is emphasized the need for early detection of the dual infection by testing all covid 19 patients for dengue in endemic areas as the disease can be more severe or one pathology can be misdiagnosed for the other.

Smart Artificial Intelligence Based Online Proctoring System

Since COVID 19, there have been significant advancements in the field of teaching and learning. Academic institutions are going digital to provide their students more resources. Due to technology, students now have more alternatives to study and improve skills at their own pace. In terms of assessments, there has been a shift toward online tests. The absence of a physical invigilator is perhaps the most significant impediment in online mode. Henceforth, online proctoring services are becoming more popular, and AI-powered proctoring solutions are becoming demanding. In this project, we describe a strategy for avoiding the physical presence of a proctor during the test by developing a multi-modal system. We captured video using a webcam along active window capture. The face of the test taker is identified and analyzed to forecast his emotions. To identify his head pose, his feature points are identified. Furthermore, aspects including a phone, a book, or the presence of another person are detected. This combination of models creates an intelligent rule-based inference system which is capable of determining if any malpractice took place during the examination. © 2022 IEEE.

Neurological Presentations of COVID-19

The plethora of neurological manifestations encountered in severe COVID-19 has been observed since the early days of the pandemic. The understanding that this is a novel condition, the magnitude of symptoms and signs of which is still being unraveled, cannot be overemphasized. This chapter offers a prelude to the rest of the book in which each category of neurological disorders will be discussed individually. © 2021 Elsevier Inc. All rights reserved.

N95 Masks: Advantages, need of Automatic Production Units and Regulatory Perspectives

The global outbreak of COVID-19 has posed one of the greatest challenges to both lives and livelihoods. Countries affected by this pandemic have adopted different approaches like hand hygiene, social distancing, quarantines, limitations to travel and large gatherings etc., and use of masks is one of them. With respect to this, different types of masks are available like surgical and N95 respirators, N95 being more efficient as compared to other face masks. Safe and quality production of these masks is yet another challenge faced by India as the country is not a major producer of Personal Protective Equipments. This article thus summarizes about the different types of masks and the need of automatic masks production units in order to avoid contamination due to human intervention. In addition, this article also highlights the importance of regulating the production of mask by Indian Regulatory Authorities as regulated by US FDA. © 2020, Indian Pharmaceutical Association. All rights reserved.

Nosocomial infections: Increased risks for immuno-compromised and COVID-19 patients

Nosocomial infections (hospital-acquired), especially Surgical Site Infections (SSIs), that lead to post-operative complications and hence increased length of stay and hospital costs are one of the primary causes of hospital deaths globally. It has been reported that operating theatres and surgical wards including fomites are contaminated with microorganisms like Pseudomonas aeruginosa and Staphylococcus aureus. Some of the potential sources identified for most life-threatening nosocomial infections include contamination of operating theatres via unfiltered air, ventilation, exogenous medical staff and personnel movements. The estimation of the quantity and types of airborne microorganisms relates to the environment cleanliness, human health risk and potential source of infections. For example, the presence of fungi indicates that outside air enters the theatre. Consequently, a linear relationship has been established between air counts of microbes in operating rooms and surgical site infection/sepsis rate. Furthermore, nosocomial skin flora of patients and staff (microbial shedding) provides yet another source. Bacteria on skin layers, lint and other dusts enter the operating theatre and might deposit on the surface. Owing to its heavy economic burden on the patient and health-care system, it is indispensable to strategize the reduction of SSI. This review thus attempts to draw the attention of the readers towards the seriousness and need to combat the hospital-acquired infections, which is often neglected. © 2021, Indian Pharmaceutical Association. All rights reserved.

When and whom should retailers offer price reductions in times of crisis?

Purpose With a decrease in consumer spending during the coronavirus disease 2019 (COVID-19) pandemic, many retailers are offering price reductions to stimulate demand. However, little is known about how consumers perceive such price reductions executed during turbulent times. The authors examine whether the timing of price reductions and individual differences impact consumers' evaluations of the retailers offering such reductions. Design/methodology/approach Using a longitudinal design, the authors inquire into four retailers' motives that consumers may infer from a price decrease at two different times during the COVID-19 crisis. Findings The authors find that the timing of price reductions plays a key role in shaping consumers' inference of retailers' motives. The authors also uncover individual characteristics that affect consumers' inferences. Originality/value This research advances the literature by demonstrating the critical role of timing and individual characteristics in consumers' perceptions of price reductions during times of crisis. The authors findings also provide retailers with actionable insights for their pricing strategies. The findings may be generalizable to other types of crises that may arise in the future.

Temporal trends in mortality and hospitalization related to SARSCOV-2 in dialysis patients in Québec (Canada)

Background: In Canada, Quebec province was the most severely hit region during the first year of the SARS-CoV-2 pandemic. We aimed to compare characteristics and outcomes of dialysis patients during the first and second SARS-CoV-2 transmission surges in this province. Methods: The QRN-COVID-HD study included adult dialysis patients from 13 units in Quebec, with SARS-CoV-2 PCR tests performed between Mar-Sept 2020 (1st wave) and Oct 2020-Feb 2021 (2nd wave). Crude and stratified rates of mortality, hospitalization and intensive care unit (ICU) admission within 90-day of SARS-CoV-2 positivity were calculated with mixed effect Poisson regressions. Adjusted predictors of 90-day outcomes were evaluated using mixed effect logistic regressions and negative binomial regressions (as appropriate). Results: Over this 12-month period, 431 patients were infected with SARS-CoV-2 (211 1st wave;220 2nd wave). Most characteristics (including age) were similar in the two waves although 2nd wave patients were less frequently living in long-term care facilities and had more diabetic nephropathy. Overall, 214 (50%) patients were hospitalized at least once and 214 (26%) died within 90-day of SARS-CoV-2 positivity, with 78% of hospitalizations and 84% of deaths directly attributed to SARS-CoV-2. Mortality and hospitalization rates were lower for 2nd compared to 1st wave patients. Figure In contrast, ICU admissions were similar in both waves (0.14, 95% CI 0.10-0.19 [1st] vs. 0.13, 95% CI 0.09-0.18 [2nd] per 100 pt-yrs). When adjusted for case-mixed differences, the 2nd wave remained associated with lower risk of mortality (OR 0.55, 95% CI 0.32-0.95), hospitalization (OR 0.45, 95%CI 0.28-0.71) and days in hospital (IRR 0.49, 95% CI 0.46-0.53), but similar risk of ICU (OR 0.73;95% CI 0.39-1.37). Conclusions: Dialysis patients with SARS-CoV-2 infections had more favorable clinical outcomes during the 2nd wave, which is consistent with observations in the general population and may be related to improved clinical care.

Feasibility of infection control measures in hemodialysis units to prevent outbreaks of COVID-19: A descriptive study from quebec

Background: In-center hemodialysis (HD) units pose the perfect conditions for COVID-19 transmission yet limited space and resources are obstacles to infection prevention and control (IPAC) measures. We aimed to describe IPAC measures implemented and document the infection rates within HD units during the first year of the pandemic. Methods: We invited leaders of Quebec's HD units to collect information on IPAC measures from March 1st to June 30th 2020 and HD unit characteristics. Participating units were contacted again in March 2021 to collect information about the total number of cases. The cumulative infection rate of each unit was compared to the regional cumulative infection rate using a standardized infection ratio (SIR). Results: Data was obtained from 38 units, representing 90% of Quebec's HD patients. 30% of units were perceived as crowded, and this was associated with objective distance measures between stations, which was much more likely to be <2m in units considered crowded (83.3% vs 19.2% p<0.001). IPAC measures regarding general prevention, screening procedures, physical distancing, and PPE use were implemented in 50% of units by 3 weeks and the remainder by 6 weeks. Data on cumulative infection rate was obtained in 26 units providing care to 3942 patients. The cumulative infection rate was disproportionally elevated in HD units compared to regional rates (Median SIR:2.68 IQR:1.58;4.45)(Figure 1). No difference was noted in the SIR related to specific IPAC measures or to the physical characteristics of the units. Conclusions: Hemodialysis units throughout Quebec were able to rapidly implement modified IPAC measures. Despite this, infection rates were disproportionally elevated.

Case series of myasthenia gravis patients with COVID-19 infection

Objective: To report the clinical course and outcome of six patients with known diagnosis of Myasthenia Gravis (MG) who developed COVID-19 infection. Background: It is hypothesized that patients with MG with COVID-19 infection may have a worse outcome given their known respiratory muscle weakness and immuno-compromised condition. There is scarce data available about their prognosis and outcomes. Design/Methods: Electronic medical records of patients with MG who developed COVID-19 were reviewed. Results: Charts of six patients with known MG who were diagnosed with COVID-19 were reviewed. Five of the patients were females, age range 36-80 years, with 4 being Caucasian. 50% were Acetylcholine receptor antibody positive. Duration for MG was between 1-5 years for most, except one patient who had the diagnosis for > 20 years. Majority of the patients presented with shortness of breath, cough, fever and myalgia except for one patient who presented with chest pain. Three were diagnosed with COVID-19 pneumonia, and 1 with subsegmental PE. Most patients were treated with IV solumedrol, plaquenil, broad spectrum antibiotics and vitamins. One patient was treated with tocilizumab. All patients were continued on their home regimen of MG treatment, with prednisone and mestinon. Imuran was also continued in one patient and Intravenous Immunoglobulin (IVIG) for another. One patient suffered an MG exacerbation and received IVIG for 5 days. Two patients were intubated for respiratory failure and suffered from other systemic complications related to COVID-19. They also had other medical co-morbidities compared to others. The length of stay ranged from 1-33 days. All patients recovered and were discharged home except for two who were discharged to rehabilitation facility. Conclusions: The prognosis of patients with MG and COVID-19 infection was favorable based on the results of these patients. The baseline immuno-suppressive therapy was not associated with worse outcomes and hence maintenance doses should be continued.

Case series of neurological complications in patients with COVID-19 infection in a tertiary care hospital

Objective: To report the clinical course, neurological complications and outcomes of thirty one patients admitted with diagnosis of COVID-19 in a tertiary care hospital. Background: There have been several case reports of various neurological manifestations of COVID-19. Patients can present with focal and or generalized neurological deficits including stroke, seizures, encephalopathy and meningitis. Design/Methods: Electronic medical records of patients who presented with or developed neurological symptoms and were diagnosed with COVID-19 were reviewed. Results: Charts of 31 patients were reviewed. Majority of the patients were male with only 7 female patients. The presenting age group varied between 35-80 years with majority of patients above the age of 60. About 50% of the patients were African American. The most common presenting neurological symptoms were acute change in mental status, followed by focal deficits including right or left hemiparesis, speech impairment (aphasia), headache and loss of sense of taste. During admission, 18 patients were diagnosed with acute stroke, 1 patient suffered from intracerebral and intraventricular hemorrhage, 2 were diagnosed with encephalitis and the rest were diagnosed with acute encephalopathy. Two patients developed seizures during their hospital course and another two patients were diagnosed with status epilepticus. All patients were treated with hydroxychloroquine, broad spectrum antibiotics, vitamins but only 50% were treated with prednisone. Two patients underwent thrombectomy, 2 received Intravenous alteplase and 2 patients received Intravenous Immunoglobulin. 20 patients required Intensive Care Unit stay and suffered from systemic complications - sepsis, respiratory failure, hypoxia and kidney failure. Majority of the patients were discharged to subacute rehabilitation, 6 were discharged home and 10 patients died. Length of stay varied between 2-45 days. Conclusions: COVID-19 can manifest with acute focal and or generalized neurological symptoms. In our experience, a third of patients presenting with/developing neurological symptoms passed away and two-thirds of patients recovered though most required rehabilitation.

Accuracy of lower temperature thresholds in detecting COVID-19 in hemodialysis patients

Background: Patients receiving in-center hemodialysis (HD) are uniquely vulnerable to COVID-19 yet identifying infected individuals may be challenging. They may not present with typical symptoms and low basal body temperature may impair detection of fever. We studied the accuracy of temperature thresholds in detecting COVID-19 in HD patients. Methods: We retrospectively studied all patients between March 24-May 14, 2020 from a single HD unit (Hôpital du Sacré-Coeur) in Montreal, Canada, where COVID-19 is highly prevalent. All patients who presented with symptoms or contact exposure were tested by nasopharyngeal swab. Prompted by an outbreak, systematic testing of all HD patients was started on April 18th. Basal temperature was defined as the average predialysis temperature from weeks -1 to -3 before testing. Diagnostic performance was determined for various temperature thresholds defined a priori. Results: Of 205 in-center HD patients, 34 developed COVID-19 during the study period. Of these, 21 (61%) were hospitalised, 4 (11%) required intensive care and 9 (26%) died. Baseline characteristics are presented in Table 1. Less than a third had typical symptoms. Thresholds of ≥ 37.3 oC and 'basal temperature +0.5 °C' had similar moderate sensitivity and high specificity in predicting COVID-19 (Table 2). Combining symptoms and either of these thresholds improved sensitivity to 85%. Conclusions: Less than one third of HD patients have typical symptoms of COVID-19 or fever >;38.0°C. Pre-dialysis temperature >;37.3°C or 0.5°C above basal temperature markedly improves sensitivity for detection of COVID-19 in asymptomatic HD patients. A screening strategy combining symptom questionnaires and pre-dialysis temperature monitoring should be used in HD units in regions of high COVID-19 prevalence.