Perspective Chapter: SARS-CoV-2 Variants - Two Years Post-Onset of the Pandemic

Since the pandemic began in China in December 2019, thousands of variants of SARS-CoV-2 have emerged globally since late 2020. The World Health Organization (WHO) defined the SARS-CoV-2 variant of concern (VOC) as a variant with increased transmissibility, virulence, and decreased response to available diagnostics, vaccines, and therapeutics. Areas of the emerging variant of concern arise from countries like the United Kingdom, South Africa, Brazil, and India. These mutations carry a lineage from N501Y, D614G, N439K, Y453F, and others, which are globally dominated by clades 20A, 20B, and 20C. SARS-CoV-2 VOC emerged after 11 months of evolution since the onset through massive human-to-human transmission with five major VOCs recognized by the WHO, namely Alpha, Beta, Gamma, Delta, and Omicron. Their emergence could be attributed to changing immunological dynamics in the human population, which has resulted in resistance or escape from neutralizing antibodies, or to mutations and/or recombinations that increase transmission or pathogenicity. This literature review intends to identify and report on SARS-CoV-2 variants that have evolved two years post-onset of the pandemic and their disease implications.

Candida auris: An Overview of the Emerging Drug-Resistant Fungal Infection

Candida auris is an invasive fungal pathogen that has been recognized globally as a serious health threat due to its extensive innate and acquired resistance to antifungal drugs. A growing number of emerging cases of C. auris have been reported with resistance to the standard antifungal treatments including azoles, echinocandins, and polyenes, making it difficult to treat. Unlike other Candida species, C. auris is challenging to diagnose using the standard laboratory methods and are typically prone to misidentification, resulting in inappropriate management. Consequently, C. auris infections have spread globally. The Centers for Disease Control and Prevention data showed that clinical cases of C. auris increased from 329 in 2018 to 1,012 in 2021. The incidence and prevalence of this invasive fungal infection are high in immunocompromised and hospitalized patients. Patients who had an organ transplant, are on immunosuppressive agents, are diabetic, recent antibiotic use, catheter use, and prolonged hospital or nursing homestays are vulnerable to C. auris infections. C. auris is rapidly spreading across healthcare settings globally and monitoring of its virulence as well as devising appropriate treatment approaches are thus highly required.

Current advancements and future prospects of COVID-19 vaccines and therapeutics: a narrative review

Coronavirus disease 2019 (COVID-19) has made a global impact on the daily lives of humanity, devastating health systems, and cataclysmically affecting the world’s economy. Currently, the Standard Public Health Protective practices consist of but are not limited to wearing masks, social distancing, isolating sick and exposed people, and contact tracing. Scientists around the globe undertook swift scientific efforts to develop safe and effective therapeutics and vaccines to combat COVID-19. Presently, as of mid-March 2022, 57.05% of the world population have been fully vaccinated, and 65.3% of the United States of America’s (USA) total population have been fully vaccinated while 76.7% have received at least one dose of the vaccine. This article explores the various vaccines created through modern science and technology, including their safety, efficacy, and mechanism of action. Although the vaccines produced are up to 95.0% efficacious, their efficacy wanes over time, underscoring the need for booster doses. Also, vaccination has not been able to prevent “breakthrough” infections. The limitations of the SARS-CoV-2 vaccines indicate that further measures are required to ensure a firm control of the COVID-19 pandemic. Therefore, the Food and Drug Administration (FDA) has issued an Emergency Use Authorization (EUA) for the use of certain therapeutic agents because they have shown remarkable clinical outcomes. Several therapeutic agents for the treatment of mild-to-moderate COVID-19 include Gilead’s remdesivir, Regeneron’s casirivimab and imdevimab combination, Eli Lilly’s baricitinib and remdesivir combination, Pfizer’s co-packaged nirmatrelvir tablets and ritonavir tablets, and Merck’s molnupiravir capsules. Hence concerted efforts in early and accurate diagnosis, education on the COVID-19 virulence, transmission and preventive measures, global vaccination, and therapeutic agents could bring this COVID-19 pandemic under control across the globe.

Cambridge hybrid closed-loop algorithm in children and adolescents with type 1 diabetes: a multicentre 6-month randomised controlled trial

BACKGROUND

Closed-loop insulin delivery systems have the potential to address suboptimal glucose control in children and adolescents with type 1 diabetes. We compared safety and efficacy of the Cambridge hybrid closed-loop algorithm with usual care over 6 months in this population.

METHODS

In a multicentre, multinational, parallel randomised controlled trial, participants aged 6-18 years using insulin pump therapy were recruited at seven UK and five US paediatric diabetes centres. Key inclusion criteria were diagnosis of type 1 diabetes for at least 12 months, insulin pump therapy for at least 3 months, and screening HbA1c levels between 53 and 86 mmol/mol (7·0-10·0%). Using block randomisation and central randomisation software, we randomly assigned participants to either closed-loop insulin delivery (closed-loop group) or to usual care with insulin pump therapy (control group) for 6 months. Randomisation was stratified at each centre by local baseline HbA1c. The Cambridge closed-loop algorithm running on a smartphone was used with either (1) a modified Medtronic 640G pump, Medtronic Guardian 3 sensor, and Medtronic prototype phone enclosure (FlorenceM configuration), or (2) a Sooil Dana RS pump and Dexcom G6 sensor (CamAPS FX configuration). The primary endpoint was change in HbA1c at 6 months combining data from both configurations. The primary analysis was done in all randomised patients (intention to treat). Trial registration ClinicalTrials.gov, NCT02925299.

FINDINGS

Of 147 people initially screened, 133 participants (mean age 13·0 years [SD 2·8]; 57% female, 43% male) were randomly assigned to either the closed-loop group (n=65) or the control group (n=68). Mean baseline HbA1c was 8·2% (SD 0·7) in the closed-loop group and 8·3% (0·7) in the control group. At 6 months, HbA1c was lower in the closed-loop group than in the control group (between-group difference -3·5 mmol/mol (95% CI -6·5 to -0·5 [-0·32 percentage points, -0·59 to -0·04]; p=0·023). Closed-loop usage was low with FlorenceM due to failing phone enclosures (median 40% [IQR 26-53]), but consistently high with CamAPS FX (93% [88-96]), impacting efficacy. A total of 155 adverse events occurred after randomisation (67 in the closed-loop group, 88 in the control group), including seven severe hypoglycaemia events (four in the closed-loop group, three in the control group), two diabetic ketoacidosis events (both in the closed-loop group), and two non-treatment-related serious adverse events. There were 23 reportable hyperglycaemia events (11 in the closed-loop group, 12 in the control group), which did not meet criteria for diabetic ketoacidosis.

INTERPRETATION

The Cambridge hybrid closed-loop algorithm had an acceptable safety profile, and improved glycaemic control in children and adolescents with type 1 diabetes. To ensure optimal efficacy of the closed-loop system, usage needs to be consistently high, as demonstrated with CamAPS FX.

FUNDING

National Institute of Diabetes and Digestive and Kidney Diseases.

Global Pandemicity of COVID-19: Situation Report as of June 9, 2020

A novel coronavirus was identified as the cause of a cluster of pneumonia cases in Wuhan, China in December 2019. This cluster quickly spread across the globe and led the World Health Organization (WHO) to declare severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) a pandemic on March 11, 2020. It's sudden emergence, ceaseless human-to-human transmission, and rapid spread has led to continuous pandemicity. As of June 9, 2020, there were 7 039 918 confirmed cases and 404 396 deaths globally. The rate of spread of COVID-19 is affected through respiratory droplets, most commonly when infected individuals cough or talk. The virus is released through respiratory secretions that infect individuals once contact with mucous membranes is made directly or indirectly. Our research was conducted via an electronic literature review on PubMed, Google Scholar, and MedLine Plus. Data were then collected from peer-reviewed articles that included applicable keywords and published between January 1, 2020, and June 9, 2020. This article highlights the rapid spread of SARS-CoV-2 worldwide and indicates a higher number of mortalities in the elderly and those with comorbidities. As the number of cases increases, an immediate need to "flatten the curve" is essential to avoid catastrophic overwhelming of hospital systems across the affected countries. To do so, there is an emphasis on detection, testing, isolating the infected, and organizing the healthcare response to the virus. The rapid spread of infection has impacted over 200 countries and territories to date. This report takes a closer look at the cases, fatalities, and recoveries in different regions of the world with details regarding the geographic scale of SARS-CoV-2 spread, risks, and the subsequent impact on the countries affected. Also, this report discusses some effective measures that were carried out by some countries that helped them to mitigate the pandemic and flatten the curve of COVID-19 spread as early as possible.

446. COVID 19 Pandemicity: a global situation report as of June 9, 2020

Background

The World Health Organization (WHO) declared severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) a pandemic on March 11, 2020. This report takes a closer look at the cases, fatalities, and recoveries in different regions of the world with details regarding the geographic scale of SARS-CoV-2 spread, risks, and the subsequent impact on the countries affected. Also, this report discusses some effective measures that were carried out by some countries that helped them to mitigate the pandemic and flatten the curve of COVID-19 spread as early as possible.

Methods

Our research was conducted via an electronic literature review on PubMed, Google Scholar, and MedLine Plus. Data were then collected from peer-reviewed articles that included applicable keywords and published between January 1, 2020, and June 9, 2020

Results

The rapid spread of infection has impacted over 200 countries and territories to date. As of June 9, 2020, there were 7,039,918 confirmed cases and 404,396 deaths globally. The USA is the North American country with the highest number of confirmed COVID 19 cases with 1,993,560. In South America, total confirmed cases in Brazil are 691,758. The most affected country in the African region is South Africa with 50,879. In Europe, the Russian Federation top with 485,253 confirmed cases. China with 84,638 is still the Western Pacific country with the most confirmed COVID 19 cases. India had 266,598 total confirmed cases and Australia reported 7,265 confirmed cases. Fatalities recorded similar patterns regionally except in Europe where the UK recorded the highest number of fatalities with 40,597 deaths and Iran had the highest number of fatalities with 5,957 cases in Asia. The goal of the practice “slowing the spread” is to prevent hospital systems from being strained beyond their capacity, thus resulting in less mortality. Countries yet to see the peak would benefit substantially by implementing aggressive social distancing, self-isolation, closure of schools and other institutions, encouraging working from home, and/or placing hard limits on the size of crowds at events.

Confirmed cases of COVID-19 globally, as of June 9, 2020.

Confirmed fatalities due to COVID-19 globally, as of June 9, 2020.

Conclusion

As the number of cases increases, an immediate need to “flatten the curve” is essential to avoid catastrophic overwhelming of hospital systems across the affected countries.

Disclosures

All Authors: No reported disclosures

Comorbidity and its Impact on Patients with COVID-19

A novel human coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in Wuhan, China, in December 2019. Since then, the virus has made its way across the globe to affect over 180 countries. SARS-CoV-2 has infected humans in all age groups, of all ethnicities, both males and females while spreading through communities at an alarming rate. Given the nature of this virus, there is much still to be learned; however, we know that the clinical manifestations range from a common cold to more severe diseases such as bronchitis, pneumonia, severe acute respiratory distress syndrome (ARDS), multi-organ failure, and even death. It is believed that COVID-19, in those with underlying health conditions or comorbidities, has an increasingly rapid and severe progression, often leading to death. This paper examined the comorbid conditions, the progression of the disease, and mortality rates in patients of all ages, infected with the ongoing COVID-19 disease. An electronic literature review search was performed, and applicable data was then collected from peer-reviewed articles published from January to April 20, 2020. From what is known at the moment, patients with COVID-19 disease who have comorbidities, such as hypertension or diabetes mellitus, are more likely to develop a more severe course and progression of the disease. Furthermore, older patients, especially those 65 years old and above who have comorbidities and are infected, have an increased admission rate into the intensive care unit (ICU) and mortality from the COVID-19 disease. Patients with comorbidities should take all necessary precautions to avoid getting infected with SARS CoV-2, as they usually have the worst prognosis.

Measles Outbreak in Unvaccinated and Partially Vaccinated Children and Adults in the United States and Canada (2018-2019): A Narrative Review of Cases

Since 2018 and currently in 2019, the United States and Canada experienced a rapidly spreading measles virus outbreak. The developing outbreak may be due to a lack of vaccination, an inadequate dosage of measles (MMR) vaccine, clusters of intentionally under-vaccinated children, imported measles from global travel, and from those who are immunocompromised or have other life-threatening diseases. The infection originated mainly from travelers who acquired measles abroad and has thus led to a major outbreak and health concern not only in the United States and Canada but also in other parts of the world. According to World Health Organization, from January 2019 through September 2019, 1234 cases of measles have been reported in the United States and 91 reported cases in Canada, while in 2018, 372 and 28 cases were reported in the United States and Canada, respectively. A potential driving factor to the increased cases maybe because fewer children have been vaccinated over the last number of years in both countries. This article is a narrative review of cases discussing the measles outbreak among partially vaccinated and unvaccinated children and adults in the United States and Canada in 2018 and 2019.

A STUDY OF THE IMAGE QUALITY OF COMPUTED TOMOGRAPHY ADAPTIVE STATISTICAL ITERATIVE RECONSTRUCTED BRAIN IMAGES USING SUBJECTIVE AND OBJECTIVE METHODS

The recent reintroduction of iterative reconstruction in computed tomography has facilitated the realisation of major dose saving. The aim of this article was to investigate the possibility of achieving further savings at a site with well-established Adaptive Statistical iterative Reconstruction (ASiR™) (GE Healthcare) brain protocols. An adult patient study was conducted with observers making visual grading assessments using image quality criteria, which were compared with the frequency domain metrics, noise power spectrum and modulation transfer function. Subjective image quality equivalency was found in the 40-70% ASiR™ range, leading to the proposal of ranges for the objective metrics defining acceptable image quality. Based on the findings of both the patient-based and objective studies of the ASiR™/tube-current combinations tested, 60%/305 mA was found to fall within all, but one, of these ranges. Therefore, it is recommended that an ASiR™ level of 60%, with a noise index of 12.20, is a viable alternative to the currently used protocol featuring a 40% ASiR™ level and a noise index of 11.20, potentially representing a 16% dose saving.

Clinical implications of machine-probe combinations on obstetric ultrasound measurements used in pregnancy dating

OBJECTIVE

To investigate the effect of use of different machine-probe combinations on measurement variability and to assess how this variability impacts on accuracy of pregnancy dating.

METHODS

Sixteen different ultrasound machine-probe combinations were used for lateral measurement of targets spaced 10 and 40 mm apart and axial measurement of targets spaced 10 and 50 mm apart in an ultrasound phantom, and differences between the measured and true values were determined. The mean of the 40-mm lateral measurements was used to estimate gestational age using standard obstetric dating tables for crown-rump length (CRL) and femur length (FL) and the mean of the 50-mm axial measurements was used to estimate gestational age using the obstetric dating tables for biparietal diameter (BPD).

RESULTS

As absolute measurements became larger, differences observed using different machine-probe combinations exceeded those due to intraobserver variability. Maximum dating differences for first-trimester CRL of 2 days (based on a measured CRL range of 39-42 mm), second-trimester BPD of 4 days (based on a measured BPD range of 49-52 mm) and FL of 9 days (based on a measured FL range of 39-42 mm) were observed when measurements were transposed to the equivalent gestational age using standard charts.

CONCLUSION

Differences between measured and true values of biometric measurements reflect both machine-probe and intraobserver variability. Incremental first-trimester CRL growth with time is rapid, but second-trimester FL growth is much less so, leaving this lateral measurement more prone to both observer and machine-probe errors. The only axial growth measurement commonly performed is BPD where the measurement differences were intermediate between those of CRL and FL. The differences that can be ascribed to different equipment combinations are in many cases greater than those expected in clinical practice and are of potential importance in determining how fetal biometry is used for dating pregnancies.

Thermographic imaging during nasal peanut challenge may be useful in the diagnosis of peanut allergy

BACKGROUND

Double-blinded challenges are widely used for diagnosing food allergy but are time-consuming and cause severe reactions. Outcome relies on subjective interpretation of symptoms, which leads to variations in outcome between observers. Facial thermography combined with nasal peanut challenge was evaluated as a novel objective indicator of clinical allergy.

METHODS

Sixteen children with positive blinded peanut challenge underwent nasal challenge with 10 μg peanut protein or placebo. Mean skin temperatures were recorded from the mouth and nose using infrared thermography over 18 min.

RESULTS

The area under curve of nasal skin temperature was significantly elevated after peanut vs placebo (18.2 vs 4.8°Cmin). The maximum increase in temperature was also significantly greater after peanut: mean difference +0.9°C.

CONCLUSION

This feasibility study shows thermography can detect inflammation caused by nasal challenges whilst employing one thousand-fold less peanut than an oral challenge. This novel technique could be developed to provide a rapid, safe and objective clinical allergy test.

Heat distribution and heat transport in bone during radiofrequency catheter ablation

BACKGROUND

To assess the feasibility of percutaneous radiofrequency ablation in large bone tumours, the heat distribution in cortical bone and marrow around inserted electrodes was measured.

METHODS

Fresh bovine cadaver tibial bones were locally heated through drill holes for a maximum of half an hour using water-cooled single radiofrequency electrodes (Radionics Instruments Inc) by pulsed energy. Temperatures were measured in the marrow canal as well as in cortical bone by thermocouples at various distances from the inserted probes.

RESULTS

Perpendicular to the probe, hyperthermia of more than 50 degrees C could be created in bone marrow in a sphere of approximately 3 cm, and of approximately 1 cm in cortical bone.

CONCLUSION

As irreversible cellular damage can be expected when increasing the temperature to 50 degrees C for a duration of 6 min, this method may be effective for the minimal invasive ablation of neoplasms within human bone in cigar-shaped regions of approximately 3-cm diameter.