Omicron variant of SARS-CoV-2: a review of existing literature.

On November 24th, 2021 a case of a new viral variant of SARS-CoV-2 was reported by South Africa and Botswana to WHO, which later was designated as the variant of concern on 26th November 2021. It has around 60 mutations (50 non synonymous, 8 synonymous, and 2 non coding) as compared to the original parent strain of Wuhan. Different hypotheses have been put forward as an explanation for the origin like reverse zoonosis i.e. animal to human transmission, origin from an immune compromised patient or use of highly mutagenic drug like molnupiravir as treatment. A huge spike in cases around the globe is suggestive of a high rate of infectivity and transmissivity as compared to the previous known variants. With whatever cases have been documented so far, it is said that omicron causes mostly mild clinical illnesses and there is a less chance of hospitalization according to the clinicians. Among the reported cases, there were already vaccinated patients also. So there is a possibility that omicron might be able to evade the vaccine induced immunity due to a huge number of mutations (especially in the spike protein sequences). Until new vaccines specific to the pathogen are being developed, the coverage of the currently acceptable vaccines should be increased so that none is deprived of the mandatory doses and a third booster dose might help to reduce the chances of serious complications of this new strain beforehand. So an equal focus on the host and environment is required along with the pathogen.

COVID-19: a viewpoint from hepatic perspective.

Coronaviruses as such are known since last century. The name is derived from their shape which has crown (corona) like radiating spikes. The recent one however is a different one from the Coronavirus involved in SARS (2002-2004) and MERS (2012) in being highly infectious. Initially COVID 19 had a high case fatality rate which has now decreased to a significant extent. Many cases of COVID 19 are asymptomatic with a significant number of positive cases developing a triad of fever, breathlessness and GI symptoms. Recent travel increases the probability of infection. The pathogenesis involves ACE 2 receptors. So, it has been found that there are more cases and mortality among hypertensive individuals. Even higher among the people who use ACE inhibitor in comparison to those who use other anti-hypertensive drugs. Treatment is usually symptomatic. Antiviral drugs and vaccines against COVID-19 are being used. Deranged liver enzymes are common in COVID-19, however, serious liver injury is not much documented. Liver injury is either due to disease itself or due to antiviral drugs. Extra care like strict social distancing, avoiding unnecessary contact is needed for those with autoimmune hepatitis, liver cancer and those who are in immunosuppression because of a scheduled or already liver transplant. Further research is definitely needed in this field. The upcoming researches should also focus on liver injuries associated with disease course and derangements arising as side effects of treatment of COVID-19.

Association of vitamin D with the severity of disease and mortality in COVID-19: Prospective study in central India.

Background: Many factors have been proposed to be associated with the severity of disease and mortality in COVID-19. Vitamin D had recently been reviewed as one of these factors. Aim and Objectives: To evaluate the association between Vitamin D and the disease severity and mortality in COVID-19. Materials and Methods: After approval from Institutional Ethics Committee, this prospective cohort study was carried out in selected tertiary care teaching medical institutes of Central India. Participants were COVID-19 patients of the age group of 18 years and above admitted during the study period. They were categorized into four groups as asymptomatic (Group A), mild (Group B), moderate (Group C), and severe (Group D) based on clinical symptoms, respiratory rate, oxygen saturation, and chest imaging. Serum level of Vitamin 25(OH) D was measured using chemiluminescent immunoassay. The outcome of the disease was classified as recovery and death during hospitalization. The association of sociodemographic and medical characteristics with treatment outcome was studied using an appropriate statistical test. A full logistic regression model was built for the assessment of the relationship between treatment outcomes with Vitamin D level. Further, one receiver operating characteristic curve was developed to examine the prognostic significance of Vitamin D levels in COVID-19 patients. Results: Out of 748 enrolled patients, 44 (5.88%), had severe disease (Group D). A total of 721 cases (96.39%) recovered and were discharged, whereas 27 (3.61%) died during hospitalization. Mean Vitamin D level was found to be significantly different in discharged patients compared to those who were deceased. Increasing age-adjusted odds ratio (AOR) (95% confidence interval [CI]=1.07 [1.02-1.12]), known hypertension AOR (95%CI) = 3.38 (1.13-10.08), and diabetes mellitus AOR (95%CI) =28.5 (6.04-134.13) were found to be significant predictors of death among COVID-19 patients. Increasing Vitamin D level was found to be protective against COVID-19-related death (AOR (95% CI = 0.87 [0.80-0.94]). Conclusion: Vitamin D was significantly associated with the disease severity and mortality in COVID-19.

Résumé Contexte: Il a été proposé que de nombreux facteurs soient associés à la gravité de la maladie et de la mortalité dans le Covid - 19. La vitamine D avait récemment été examinée comme l'un de ces facteurs. Objectif et objectifs: évaluer l'association entre la vitamine D et la gravité de la maladie et la mortalité dans le Covid-19. Matériel et méthodes: Après l'approbation du comité d'éthique institutionnel, cette étude de cohorte prospective a été réalisée dans des instituts médicaux d'enseignement des soins tertiaires de l'Inde centrale. Les participants étaient des patients Covid-19 du groupe d'âge de 18 ans et plus admis au cours de la période d'étude. Ils ont été classés en quatre groupes comme asymptomatiques (groupe A), légers (groupe B), modérés (groupe C) et sévères (groupe D) sur la base des symptômes cliniques, de la fréquence respiratoire, de la saturation en oxygène et de l'imagerie thoracique. Niveau sérique de la vitamine 25 (OH) DWAS mesuré en utilisant l'immunodosage chimioluminescent. L'issue de la maladie a été classée comme récupération et décès pendant l'hospitalisation. L'association des caractéristiques sociodémographiques et médicales avec les résultats du traitement a été étudiée à l'aide d'un test statistique approprié. Un modèle de régression logistique complet a été construit pour l'évaluation de la relation entre les résultats du traitement au niveau de la vitamine D. De plus, une courbe caractéristique de fonctionnement du récepteur a été développée pour examiner la signification pronostique des niveaux de vitamine D chez les patients COVID-19. Résultats: Sur 748 patients inscrits, 44 (5,88%), avaient une maladie grave (groupe D). Un total de 721 cas (96,39%) ont récupéré et ont été libérés, tandis que 27 (3,61%) sont décédés pendant l'hospitalisation. Le niveau moyen de la vitamine D s'est révélé significativement différent chez les patients libérés par rapport à ceux qui ont été décédés. Augmentation du rapport de cotes ajusté à l'âge (AOR) (intervalle de confiance à 95% [IC] = 1,07 [1,02­1,12]), hypertension connue AOR (IC à 95%) = 3,38 (1,13­10,08) et diabète mellite aor (IC 95% ) = 28,5 (6,04­134.13) se sont révélés être des prédicteurs significatifs de la mort chez les patients COVID-19. L'augmentation du niveau de vitamine D s'est avérée protectrice contre la mort liée au Covid - 19 (AOR (IC à 95% = 0,87 [0,80­0,94]). Conclusion: La vitamine D était significativement associée à la gravité de la maladie et à la mortalité dans le Covid - 19. Mots clés: Covid - 19, tempête de cytokines, mortalité, gravité, vitamine D.

COVID-19: Origin, epidemiology, virology, pathogenesis, and treatment

COVID-19 (or Coronavirus Disease) originated in China (Hubei provenance, Wuhan city). The first recorded illness occurred in December 2019. It has affected all parts of the world, and the WHO designated the COVID-19 disease, caused by the new Coronavirus SARS-CoV-2, a pandemic on March 11, 2020. Some debatable speculations indicate that it is a man-made virus, intentionally synthesized in the laboratory but was unintentionally emancipated from a laboratory of Wuhan, China. The primitive theory suggested the spread from the Hunan seafood market of China probably from an animal source. However, this theory is not fully supported. COVID-19 infection has a varying range of signs and symptoms from low fever, dry cough to lower respiratory tract infection, breathing difficulties, pulmonary edema, acute respiratory distress syndrome (ARDS), metabolic acidosis, sepsis, coagulation, lymphopenia, hypoxemia, multiorgan failure, and eventually, mortality. In patients with comorbidity such as diabetes, cardiovascular disease, high blood pressure, stroke, and kidney disease, fatality rate is higher. Young and elderly people are more likely to experience unfavorable outcomes due to poor immunity. There have been several treatment methods explored to tackle the COVID-19 pandemic, including medications, interferon, vaccines, oligonucleotides, peptides, and monoclonal and immunomodulatory antibodies, among other things. The World Health Organization has recommended preventive measures like washing hands, using face masks, sanitizers, and maintaining a safe distance to prevent the spread of the pandemic. One of the promising alternatives is the vaccine. One must take all preventive measures in the pandemic until it becomes feeble.

The study of serum hsCRP, ferritin, IL-6 and plasma D-dimer in COVID-19: a retrospective study.

OBJECTIVES: The cut off values for serum high sensitivity C-reactive protein (hsCRP), ferritin, interleukin 6 (IL-6) and plasma D-dimer could be of profound help in detecting COVID-19 patients at risk of adverse outcomes. Therefore, the aim of the present study is to determine the cut off values of the serum hsCRP, ferritin, IL-6 and plasma D-dimer in predicting mortality in COVID-19 patients. METHODS: Four hundred RT-PCR confirmed cases of COVID-19 were sub divided into two groups based on their outcome during hospitalisation. Group I consisted of survivors and Group II consisted of non-survivors. The survivors were further divided into three sub-groups: mild, moderate and severe based on the severity of infection. The laboratory data of serum hsCRP, ferritin, IL-6 and plasma D-dimer for all these patients was retrieved from the Medical Record Section of the Hospital. RESULTS: Mean serum hsCRP, ferritin, IL-6 and plasma D-dimer levels were significantly higher in non-survivors as compared to survivors of COVID-19. The levels of these biomarkers correlated with the severity of COVID-19 illness. ROC curve analysis revealed that plasma D-dimer is having a better predictive value as compared to other parameters in predicting mortality in COVID-19. CONCLUSIONS: The serum hsCRP, ferritin, IL-6 and plasma D-dimer levels could be used in risk stratification of COVID-19 patients. The optimum cut off given by the current study could be considered in predicting adverse outcome in these patients. Amongst the many studied biomarkers, plasma D-dimer might be the best early biomarker to predict mortality in COVID-19 patients.

COVID-19 infection in pregnancy: a review of existing knowledge.

The world has been coping up with the grave pandemic of COVID-19 since its inception into the human race in December, 2019. By entering the host through the spike (S) glycoprotein, it paves way for its own survival and multiplication. Respiratory tract being the point of entry causes pulmonary compromise and leads to development of ARDS. Having non-specific clinical features that resemble flu makes the clinical diagnosis much more difficult. Pregnancy being an immunocompromised and a hypercoagulable state is prone to be a high-risk group for COVID-19. This study is an attempt to understand the maternal and fetal outcomes in COVID-19 and the vertical transmissibility of the virus. Evidence suggests that the contribution of COVID-19 is not very significant in maternal morbidity and mortality. However, due to some factors such as the immunological response in the mother, certain complications may arise in the neonate in the post-natal period. No vertical transmission of the virus has been reported yet. However, the management remains crucial as two lives are at stake. Some of the precautionary measures that can be implemented to prevent COVID-19 can be segregation of medical services from that of the general population in settings of outpatient care, inpatient care and labor room care. Also, triaging the patients into low risk, moderate risk and high risk can aid in faster delivery of health-care facilities to the pregnant and the newborn.

The second wave of COVID-19 results in outbreak of mucormycosis: diabetes and immunological perspective.

OBJECTIVES: To evaluate the potential relationship between COVID-19 pandemic and mucormycosis outbreak. METHODS: PubMed, Embase, Cochrane Library and Google Scholar were searched for the term "COVID-19 and mucormycosis" up to May 31, 2021. RESULTS: After the second wave of COVID-19, the mucormycosis outbreak complicates the natural course of COVID-19. COVID-19 patients with uncontrolled diabetes mellitus with diabetic ketoacidosis, excessive glucocorticoid use, prolonged neutropenia, malnutrition and any underlying immunocompromised conditions are at risk of developing mucormycosis. CONCLUSIONS: Hyperglycaemia impairs the motility of phagocytes and also decreases the oxidative and non-oxidative mechanism of killing the causative pathogen. Chronic hyperglycemia also leads to the formation of advanced glycation end-products (AGE), which leads to cross-linking between key proteins of inflammation and connective tissue such as collagen which makes tissue susceptible to immunological dysregulation. The receptor for AGE (RAGE) is expressed on various inflammatory cells including neutrophils and its activation by AGEs leads to activation of many down signaling pathways which ultimately leads to impairment of the inflammatory response. Hyperglycemia also increases serum Nitric Oxide (NO), which decreases neutrophil motility and reduces the synthesis and release of various inflammatory mediators such as TNF-α and IL-1ß, IL-6. It also decreases the expression of adhesion molecules such as LFA-1 and ICAM-2, on neutrophils. Steroids cause immunosuppression majorly by inhibiting the NF-κB pathway which is a transcription factor involved in the synthesis of many immunological mediators such as Interleukins, cytokines, chemokines, etc., and various adhesion molecules.

COVID-19 pandemic and potential of artificial intelligence.

OBJECTIVE: To evaluate the potential of artificial intelligence in combating COVID-19 pandemic. METHODS: PubMed, Embase, Cochrane Library and Google Scholar were searched for the term "Artificial intelligence and COVID-19" up to March 31, 2021. RESULTS: Artificial intelligence (AI) is a potential tool to contain the current pandemic. AI can be used in many fields such as early detection and respective diagnosis, supervision of treatment, projection of cases and mortality, contact tracing of individuals, development of drugs and vaccines, reduces workload on health workers, prevention of disease, analysis of mental health of people amid pandemic. CONCLUSIONS: AI is being updated and being improved, second by second to be able to interpret like actual human minds. This advancement in AI may lead to a completely different future of COVID-19 pandemic where most of the simpler works may be done by AI and only essential works could be done by health workers in order to increase patient care in current scenario of COVID-19 outbreak. But again one of the main constraint is of limited trustworthy and noise free sources of information. So the need for the hour is to make a free data system where most of the analysed data could be available to feed AI, which could effectively halt the current pandemic.

COVID-19 and lung pathologies.

COVID-19 is a global emergency with over 10 million cases and over 500, 000 deaths worldwide. The SARS CoV-2 is a RNA virus belonging to the family coronaviridae. It has high infectivity. The manifestations of the disease range from asymptomatic or mild symptoms to severe pneumonia and ARDS. The CT scan of lung shows consolidation and "Ground Glass Opacities". The persons with other comorbidities are considered to be at a higher rate of acquiring the infection. Asthma and other allergies have not been identified as major risk factors for COVID-19 as the number of asthmatic patients having COVID-19 is not high enough for it to be considered so. The occurrence of COVID-19 in COPD patients can be related with smoking. The ACE-2 expression in such patients was considerably high. The relation between COVID-19 and Tuberculosis can also be reflected in terms of the stigma associated with diagnosis and treatment of such diseases in some communities, eventually increasing the chances of people's reluctance to seek medical help. Cancer patients are usually more susceptible to infections. Lung cancer is no different. Additionally, lung cancer also has strong association with smoking further increasing the risk. The risk of getting infection and its severity is high for autoimmune disorders as well as fungal infections. Currently there is no definite treatment of COVID-19. However, some of the currently used modalities are hydroxychloroquine and antiviral drugs.

COVID-19 and neurology perspective.

COVID-19 caused by SARS CoV2 (The novel corona virus) has already taken lives of many people across the globe even more than anyone could have imagined. This outbreak occurred in China and since then it is expanding its devastating effects by leaps and bounds. Initially it appeared to be an outbreak of pneumonia but soon it was found to be much more than that and the infectivity was found to be very high. This is the reason that it has taken whole globe in its trap and become a pandemic in such a short span of time. Death is occurring because it is a new virus and human body has no specific antibodies for it. Presently there is no approved vaccine so everyone is susceptible but people with co-morbidities appear to be in more risk and the best way for protection is social distancing and increasing one's natural immunity by taking healthy diet and exercise. When a person is infected the clinical presentation ranges from asymptomatic to severe ARDS, sudden onset of anosmia, headache, cough may be the initial symptoms. This review is focused on immunopathology and effect of COVID-19 on neurological disorders and also the neurological manifestations and the treatment.

COVID-19: a review on SARS-CoV-2 origin, epidemiology, virology, clinical manifestations and complications with special emphasis on adverse outcome in Bhopal Gas Tragedy survivor.

After the global outbreak of coronaviruses caused diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS), an outbreak due to these viruses occurred in December, 2019 in Wuhan, Hubei Province, China and led to a worldwide spread. Coronavirus 2019 disease (COVID-19) has emerged as a serious global health emergency and spread from a person to another who has the virus. But the scope of an intermediate host is not known. Population at higher risk includes individuals in higher age group (>60 years) or with comorbidities such as diabetes, hypertension, cardiovascular disease and weaker immune system. Many unknown and underestimate risk factors could be responsible for adverse outcomes in COVID-19. These risk factors should be appropriately identified, addressed and necessary actions should be taken to mitigate the effect of COVID-19 pandemic. Bhopal gas tragedy was one of the world's worst industrial chemical leak disaster. The survivors of this incident still suffer from the various complications such as increased rate of cancers, chronic illness like tuberculosis, respiratory diseases, birth defects, nerve injury, growth retardations, gynecological illness and many more. The survivors of Bhopal gas tragedy are at higher risk of developing COVID-19 related adverse outcome. One of the possible explanations can be long term effect of methyl isocyanate (MIC). MIC exposure can lead to possible toxic effect on genetic, epigenetic and non-genetic factors. In this review, we aim to establish the scientific basis for adverse outcome in COVID-19 patients who are also victims of Bhopal gas tragedy.

COVID-19 and nutritional deficiency: a review of existing knowledge.

COVID-19 has resulted in an ongoing global pandemic, which spread largely among people who have had close contact with the infected person. The immunopathology of the SARS-CoV-2 virus includes the production of an excess amount of pro-inflammatory cytokines "a cytokine-storm". The respiratory system (main), cardiovascular system and the gastrointestinal tract are the most affected body systems during viral infection. It has been found that most of the patients who require admission to hospital are elderly or have chronic underlying diseases. Higher cases of malnutrition and co-morbidities like diabetes mellitus and cardiovascular diseases are reported in elderly patients due to which, the immune system weakens and hence, the response to the virus is diminished in magnitude. A deficiency of micronutrients results in impaired immune responses leading to improper secretion of cytokines, alterations in secretory antibody response and antibody affinity which increases susceptibility to viral infection. The deficiency of various micronutrients in COVID-19 patient can be treated by appropriate nutritional supplements, prescribed after evaluating the patients' nutritional status. Here we aim to highlight the role of a few particular nutrients namely Vitamin D, Vitamin C, Omega-3 fatty acids, Zinc and Magnesium along with the synergistic roles they play in enhancing immunity and thus, maintaining homeostasis.

COVID-19 and geriatric population: from pathophysiology to clinical perspectives.

The COVID-19 pandemic has not only led to a worldwide socio-economic depression, but has also had the highest health impact on the geriatric population. Elderly population, due to various reasons such as low immunity, pre-existing co-morbidities such as hypertension, cardiovascular diseases or diabetes, are obviously predisposed to develop severe infections and exhibit a high mortality rate. This is because of many reasons which include the atypical presentation in the geriatric population which might have led to diagnostic delay. As per the WHO guidelines to perform RT-PCR only on the symptomatic individuals, a very small portion of individuals were tested, leaving a fraction of population undiagnosed. Therefore, there remained a chance that many asymptomatic individuals such caregivers, healthcare professionals, family members were undiagnosed and might have carried this virus to the geriatric patients. Also, many countries were not prepared to handle the burden on their healthcare system which included sudden increased demand of ICU beds, mechanical ventilation etc. As a result, they had to make decision on who to be admitted. Atypical presentation in geriatric population may include afebrile or low-grade fever, absence of cough, malaise, muscle pains, dyspnoea etc. Geriatric population shows a more severe type of pneumonia, significantly higher number of neutrophils and C-reactive protein, less lymphocytes and a higher proportion of multiple lobe involvement. Extreme social suppression during COVID-19 pandemic has increased the risk of mental and physical adverse effects that has made older adults more vulnerable to depression and anxiety.

COVID-19 and cardiovascular disease: a review of current knowledge.

The uncontrolled spread of the COVID-19 pandemic which originated in China created a global turmoil. While the world is still busy figuring out a cure for the deadly disease, scientists worked out on many theories and conducted several studies to establish a relationship between the infection and other known diseases. Cardiovascular diseases (CVD) are one of the major complications of this infection after the respiratory manifestations. Individuals with cardiovascular complication are said to be more susceptible to acquiring the infection because the novel coronavirus uses the ACE2 receptor for its entry inside the cell and there is a high level of ACE2 expression in individuals with cardiovascular complications because of the enzyme's anti-hypertrophic, anti-fibrotic and anti-hypertensive effects on the heart. Individuals who belong to the older age group are also more susceptible. Knowing the above information, it might seem that using ACE2 inhibitors would help to slow or prevent the entry of the novel coronavirus but it would also at the same time prove to have deleterious effects on the cardiovascular system as the protective functions of ACE2 would be lost. While the search for a cure still continues it has been stated many a times that the conditions might worsen with time and the only way to keep ourselves and our family safe would be to follow the appropriate social distancing methods and get a COVID test if we experience any of the major symptoms.