COVID-19-Related Anosmia: The Olfactory Pathway Hypothesis and Early Intervention

Potential convergence of olfactory dysfunction in Parkinson's disease and COVID-19: The role of neuroinflammation

Parkinson's disease (PD) is a prevalent neurodegenerative disorder that affects 7-10 million individuals worldwide. A common early symptom of PD is olfactory dysfunction (OD), and more than 90% of PD patients suffer from OD. Recent studies have highlighted a high incidence of OD in patients with SARS-CoV-2 infection. This review investigates the potential convergence of OD in PD and COVID-19, particularly focusing on the mechanisms by which neuroinflammation contributes to OD and neurological events. Starting from our fundamental understanding of the olfactory bulb, we summarize the clinical features of OD and pathological features of the olfactory bulb from clinical cases and autopsy reports in PD patients. We then examine SARS-CoV-2-induced olfactory bulb neuropathology and OD and emphasize the SARS-CoV-2-induced neuroinflammatory cascades potentially leading to PD manifestations. By activating microglia and astrocytes, as well as facilitating the aggregation of α-synuclein, SARS-CoV-2 could contribute to the onset or exacerbation of PD. We also discuss the possible contributions of NF-κB, the NLRP3 inflammasome, and the JAK/STAT, p38 MAPK, TLR4, IL-6/JAK2/STAT3 and cGAS-STING signaling pathways. Although olfactory dysfunction in patients with COVID-19 may be reversible, it is challenging to restore OD in patients with PD. With the emergence of new SARS-CoV-2 variants and the recurrence of infections, we call for continued attention to the intersection between PD and SARS-CoV-2 infection, especially from the perspective of OD.

Prevalence and association of oral manifestations with disease severity in patients diagnosed with COVID‑19: A cross‑sectional study

Systemic disorders may exhibit early signs when conducting an oral examination. Since the onset of the COVID-19 pandemic, several studies have been published detailing the direct impact of the virus on the oral cavity. The present study aimed to determine whether indeed there are any significant disparities in oropharyngeal manifestations between individuals infected with severe acute respiratory syndrome coronavirus 2 and a control group, and whether the virus has the ability to invade and reproduce inside oral keratinocytes and fibroblasts, resulting in the development of oral ulcerations and superficial lesions. The present study provides an overview of the symptoms that occur at an early stage of the illness, and the most commonly affected regions of the oral cavity, including the tongue, lips, palate and oropharynx are examined. In the present retrospective study, 52 patients infected with COVID-19 were recruited between April, 2021 and October, 2022. In addition, 52 individuals who tested negative for the virus were recruited as the control group. The study was conducted through a thorough examination and questionnaire provided to all participants. The results revealed that among the cohort of patients from the COVID-19 group examined (n=52), a proportion (mean, 16.15) displayed oral manifestations. Specifically, 75% of the patients in the COVID-19 group described oral cavity pain, and 69% of these patients had changes in teeth color or dental caries. In summary, in relation to the control group, the prevalence of oropharyngeal symptoms was generally lower compared to the COVID-19 group, apart from oral cavity pain (30.8%), tonsillitis (17.3%), bleeding (34.6%), teeth color changes (36.5%), recurrence (15.4%) and abscesses (7.7%). Thus, on the whole, the patients without COVID-19 had fewer oral manifestations.

The Efficacy of Sodium Phytate as a Natural Chelating Agent in Reducing Elevated Calcium Levels in Nasal Mucus Among Individuals Experiencing Olfactory Dysfunction Following COVID-19: A Prospective Randomized Double-Controlled Clinical Trial

BACKGROUND

COVID-19 has been associated with olfactory disturbances in many infected patients. The increase in calcium levels in nasal secretions plays an essential role in the olfactory process with a desensitizing effect on olfactory receptor neurons and negative effects on odor transmission. Calcium chelating agents have the ability to bind calcium in nasal mucus and prevent the negative effects associated with calcium increase.

OBJECTIVES

The aim of this work is to demonstrate the intra-nasal topical application of sodium phytate, an environmentally friendly, non-harmful calcium chelating agent, to reduce the adverse effects of calcium on olfactory function and improve olfactory dysfunction according to COVID-19.

METHODS

Fifty-two patients with a previous COVID-19 and olfactory dysfunction lasting longer than 90 days were enrolled in a prospective, randomized, blinded, controlled clinical trial. Patients were divided into two equal groups: 26 patients received nasal spray containing 0.9% sodium chloride and 26 patients received nasal spray containing 1% sodium phytate. Olfactory function was measured before treatment and 1 month later using the Sniffin' Sticks test. Calcium content of nasal secretions was determined before and after treatment with an ion-selective electrode.

RESULTS

A significant improvement from anosmia to hyposmia was demonstrated after the use of sodium phytate compared with no improvement after the use of sodium chloride. In addition, a decrease in the level of calcium in nasal secretions was observed after the use of sodium phytate.

CONCLUSION

Sodium phytate has benefit role on improving the olfactory function after COVID-19.

COVID-19 and brain-heart-lung microbial fingerprints in Italian cadavers

Introduction: The fact that SARS-CoV-2, the coronavirus that caused COVID-19, can translocate within days of infection to the brain and heart and that the virus can survive for months is well established. However, studies have not investigated the crosstalk between the brain, heart, and lungs regarding microbiota that simultaneously co-inhabit these organs during COVID-19 illness and subsequent death. Given the significant overlap of cause of death from or with SARS-CoV-2, we investigated the possibility of a microbial fingerprint regarding COVID-19 death. Methods: In the current study, the 16S rRNA V4 region was amplified and sequenced from 20 COVID-19-positive and 20 non-COVID-19 cases. Nonparametric statistics were used to determine the resulting microbiota profile and its association with cadaver characteristics. When comparing non-COVID-19 infected tissues versus those infected by COVID-19, there is statistical differences (p < 0.05) between organs from the infected group only. Results: When comparing the three organs, microbial richness was significantly higher in non-COVID-19-infected tissues than infected. Unifrac distance metrics showed more variance between control and COVID-19 groups in weighted analysis than unweighted; both were statistically different. Unweighted Bray-Curtis principal coordinate analyses revealed a near distinct two-community structure: one for the control and the other for the infected group. Both unweighted and weighted Bray-Curtis showed statistical differences. Deblur analyses demonstrated Firmicutes in all organs from both groups. Discussion: Data obtained from these studies facilitated the defining of microbiome signatures in COVID-19 decedents that could be identified as taxonomic biomarkers effective for predicting the occurrence, the co-infections involved in its dysbiosis, and the evolution of the virus.

COVID-19 in Pediatric Patients: A Study Based on Biomarker Levels

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected people of all ages, but limited data are available on children with mild and severe coronavirus disease 2019 (COVID-19).

METHODS

Clinical characteristics, inflammation, and other biochemical biomarkers have been described, but information is scarce in asymptomatic and mild cases. Laboratory investigations were performed with pediatric patients (n=70) for liver function and kidney function, along with C-reactive protein (CRP).

RESULTS

Mild clinical characteristics and symptoms were observed in pediatric patients. Even in moderate cases of COVID-19, elevated levels of biomarkers indicate altered liver and kidney function in children. The levels of liver enzymes, bilirubin, creatinine, and CRP varied significantly between the three classes, particularly between asymptomatic and moderate cases. Liver enzymes, bilirubin, and creatinine levels in moderate COVID-19 pediatric cases were twice as elevated as in asymptomatic cases. Liver enzymes and CRP levels were moderately elevated.

CONCLUSION

Monitoring blood biomarkers consistently can assist in the accurate identification of infection in young patients as well as in the prevention of its spread and the administration of appropriate treatment.

Is Olfactory Testing a Useful Diagnostic Tool to Identify SARS-CoV-2 Infections Early? A Cross-Sectional and Longitudinal Analysis

BACKGROUND

Genesis and the prognostic value of olfactory dysfunction (OD) in COVID-19 remain partially described. The objective of our study was to characterize OD during SARS-CoV-2 infection and to examine whether testing of OD may be a useful tool in clinical practice in order to early identify patients with SARS-CoV-2 infection.

METHODS

Olfactory function assessment was objectively carried out using the u-Smell-it^® test. In a cross-sectional study part, we evaluated this test in a control cohort of SARS-CoV-2 negative tested patients, who attended the University Hospital Frankfurt between May 2021 and March 2022. In a second longitudinal study part, sensitivity and specificity of OD was evaluated as a diagnostic marker of a SARS-CoV-2 infection in Frankfurt am Main, Germany in SARS-CoV-2 infected patients and their close contacts.

RESULTS

Among 494 SARS-CoV-2 negative tested patients, OD was detected in 45.7% and was found to be significantly associated with the male gender (p < 0.001), higher age (p < 0.001), cardiovascular and pulmonary comorbidities (p < 0.001; p = 0.03). Among 90 COVID-19 positive patients, OD was found in 65.6% and was significantly associated with male gender and positive smoking status (p = 0.04 each). Prevalence and severity of OD were significantly increased in infections with the Delta variant (B.1.617.2) compared to those with the Omicron variant (BA.1.1.529). Diagnostic sensitivity and specificity of OD for diagnosis of SARS-CoV-2 infection were 69% and 64%, respectively.

CONCLUSION

OD is common in COVID-19 negative and positive tested patients with significantly different prevalence rates observed between different variants. Diagnostic accuracy of OD is not high enough to implement olfactory testing as a tool in diagnostic routine to early identify patients with a SARS-CoV-2 infection.

Study of some immunological signatures and their association with COVID-19 in a sample of recovered Iraqi patients

Since its emergence about two years ago, the novel coronavirus has continued to be a challenge and threat to public health, struck most parts of the world, leaving more than half a billion cases of infection and more than five million deaths. Immune response abnormalities post-infection with SARS-CoV-2 have been reported, and the mechanisms that lead to them are still ambiguous. This study was conducted to evaluate some immunological markers in the serum samples of COVID-19 convalescent patients and investigate the association of these immunological signatures with their age and sex. The serum levels of immunoglobulin G, interleukin-1 beta, and interferon lambda-1 of 75 patients and 50 healthy control group members were measured, with 55 % males and 45 % females participating and ages ranging from 20 to 80 years. The measurement of the immunological signatures was performed using the enzyme-linked immunosorbent assay (ELISA). The result revealed highly significant elevated levels of the serum immunological signatures of the convalescent group in comparison to the control group, with P-values of 0.00001 for each signature. Moreover, age was observed to have an association with an elevated level of the immunological signatures as it increased in the elderly, whereas no association with sex was detected. The findings strongly suggest that COVID-19 infection results in a persistent inflammatory response, which leads to prolonged post-recovery symptoms. Post-COVID-19 syndrome necessitates additional research to clarify its pathophysiology, pathogenesis, and long-term implications.

Exploring the research landscape of COVID-19-induced olfactory dysfunction: A bibliometric study

Since the outbreak of COVID-19, olfactory dysfunction (OD) has become an important and persistent legacy problem that seriously affects the quality of life. The purpose of this paper is to quantitatively analyze and visualize the current research status and development trend of COVID-19 related OD by using VOSviewer software. Based on the Web of Science database, a total of 1,592 relevant documents were retrieved in January 2023, with publication time spanning from 2020 to 2023. The bibliometric analysis revealed that the most influential research results in the field of COVID-19 related OD were concentrated in journals of related disciplines such as otorhinolaryngology, medicine, general and internal, virology, neurosciences, etc. The knowledge base of the research is mainly formed in two fields: COVID-19 clinical research and OD specialized research. The research hotspots are mainly concentrated in six directions: COVID-19, long COVID, smell, anosmia, OD, and recovery. Based on the results of the bibliometric analysis, the temporal trends of COVID-19 related OD studies were visually revealed, and relevant suggestions for future research were proposed.

Anosmia-An Effect of COVID-19 Infection-Review

The World Health Organization announced on March 11, 2020 that COVID-19 could become a pandemic. COVID-19 is a contagious disease caused by the coronavirus that causes severe acute respiratory syndrome (SARS-CoV-2). Viruses usually enter the body through the mouth or nose. The virus then enters the alveoli, which are small air sacs inside the lungs. Cough, fatigue, fever, shortness of breath or breathing difficulties, and loss of smell and taste are all symptoms of COVID-19. Anosmia, also known as smell blindness, is a condition in which the ability to detect one or more smells is lost. Olfaction uses chemoreceptors to create signals that are processed in the brain and form the sense of smell in anosmia. Anosmia is recognised as a COVID-19 symptom in many countries, and some have developed "smell tests" as potential screening tools. The first level of screening, which is currently used in India, is primarily based on temperature and can result in false positives and negatives (fever as a symptom has not yet been developed although infection). One of the methods for detecting COVID-19 is an intermediate level of screening based on assessing an olfactory function, depending on the usage. This paper provides an overview of COVID-19 and its effects on the human body, as well as an overview of anosmia and how it contributes to one of the symptoms of COVID-19.

COVID-19, Anosmia, and Allergies: Is There a Relationship? A Pediatric Perspective

Background: Between June and July 2020, we evaluated children and adolescents concerning post-infection surveillance after a COVID-19 positivity during the lockdown. We aimed to assess whether the anamnestic presence of allergies could correlate with the presence of SARS-CoV-2 symptoms, and in particular with anosmia. Material and methods: For each patient, we collected anamnestic data, the presence of allergies documented by performing skin prick tests, and COVID-19 symptoms. Then, if over six years of age, each patient underwent an active anterior rhinomanometry. Results: A total of 296 patients were enrolled, of whom 105 (35.4%) reported allergies. Considering COVID-19 symptoms, 74 subjects (25%) presented an asymptomatic form, 222 (75%) reported symptoms, and anosmia recurred in 60 subjects (27.03%). A statistically significant relationship was found between allergies and symptomatic COVID-19 (p = 0.042), allergies, and anosmia (p = 0.05), and allergies and anosmia in males (p = 0.007). Moreover, anosmic patients presented a higher body mass index, older age, and a longer COVID-19 duration with statistical significance (p = 0.001, 0.001, 0.006, respectively). Conclusions: Allergic subjects seem to develop symptomatic COVID-19 more frequently and allergies appear to be a protective factor from anosmia’s onset in males.

The association of airborne particulate matter and benzo[a]pyrene with the clinical course of COVID-19 in patients hospitalized in Poland

Air pollution can adversely affect the immune response and increase the severity of the viral disease. The present study aimed to explore the relationship between symptomatology, clinical course, and inflammation markers of adult patients with coronavirus disease 2019 (COVID-19) hospitalized in Poland (n = 4432) and air pollution levels, i.e., mean 24 h and max 24 h level of benzo(a)pyrene (B(a)P) and particulate matter <10 μm (PM₁₀) and <2.5 μm (PM_2.5) during a week before their hospitalization. Exposures to PM_2.5 and B(a)P exceeding the limits were associated with higher odds of early respiratory symptoms of COVID-19 and hyperinflammatory state: interleukin-6 > 100 pg/mL, procalcitonin >0.25 ng/mL, and white blood cells count >11 × 10³/mL. Except for the mean 24 h PM₁₀ level, the exceedance of other air pollution parameters was associated with increased odds for oxygen saturation <90%. Exposure to elevated PM_2.5 and B(a)P levels increased the odds of oxygen therapy and death. This study evidences that worse air quality is related to increased severity of COVID-19 and worse outcome in hospitalized patients. Mitigating air pollution shall be an integral part of measures undertaken to decrease the disease burden during a pandemic of viral respiratory illness.

COVID-19 and abducens nerve palsy in a 9-year-old girl-case report

Background

Coronavirus disease 2019 (COVID-19) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although many reports have detailed a range of neurological symptoms in SARS-CoV-2-infected patients, studies of neuro-ophthalmological manifestations are still scarce.

Case presentation

We report a 9-year-old girl with abducens nerve palsy after COVID-19 with no evidence of other neurological disease on neuroimaging. At 2-month follow-up clinical conditions were improved.

Conclusions

The palsy may have occurred due to a possible post-infectious immune-mediated mechanism underlying the neuropathy, as opposed to direct viral infiltration. Despite being rare, this complication must be taken into account.

Effects of COVID-19 lockdown on weight in a cohort of allergic children and adolescents

BACKGROUND

COVID-19 lockdown caused sudden changes in people's lifestyle, as a consequence of the forced lockdown imposed by governments all over the world. We aimed to evaluate the impact of lockdown on body mass index (BMI) in a cohort of allergic children and adolescents.

METHODS

From the first of June until the end of October 2020, we submitted a written questionnaire to all the patients who, after lockdown, carried out a visit at the Pediatric Allergy Unit of the Department of Mother-Child, Urological Science, Sapienza University of Rome. The questionnaire was composed by 10 questions, referring to the changes in their daily activities. Data were extrapolated from the questionnaire and then analyzed considering six variables: BMI before and BMI after lockdown, sugar intake, sport, screens, sleep, and anxiety.

RESULTS

One hundred fifty-three patients agreed to answer our questionnaire. Results showed a statistically significant increase in the BMI after lockdown (20.97 kg/m2 ± 2.63) with respect to the BMI before lockdown (19.18 kg/m2 ± 2.70). A multivariate regression analysis showed that the two variables that mostly influenced the increase in BMI were sleep and anxiety.

CONCLUSIONS

For the analyzed cohort of allergic children and adolescents we obtained significant gain in BMI as consequences of lockdown, which can be explained by many factors: high consumption of consolatory food, less sport activities, more time spent in front of screens, sleep alteration associated with increased anxiety. All these factors acted together, although sleep alteration and increased anxiety were the most influential factors that led to the worsening or the onset of weight gain, creating the basis for future health problems.

Impact of screen exposure on pediatric vernal Keratoconjunctivitis: a survey during the COVID-19 pandemic in Italy

BACKGROUND

The SARS-CoV-2 outbreak pushed the Italian government to start a strict lockdown, replacing school attendance with long-distance learning. This caused reduced exposure to sunlight but increased exposure to screens. Vernal keratoconjunctivitis (VKC) is a chronic inflammatory ocular condition in which exposure to light plays a cardinal role. We conducted an online survey to evaluate the impact of screen exposure on children with VKC during the COVID-19 lockdown.

METHODS

We performed a survey-based observational study, asking patients followed at the Allergology clinics of Meyer Children's University Hospital in Florence and of Policlinico Umberto I in Rome to provide grading on 6 subjective ocular clinical manifestations presented during the lockdown and to give an estimate of their hours/day of screen exposure.

RESULTS

Mean scores of signs and symptoms increased homogeneously when studying patients exposed to longer screen time. When comparing scores collected in 2019 to those in 2020, there was not a significant reduction in clinical manifestations, although the situation differed between the two centers due to geographical differences in sunlight exposure.

CONCLUSION

During the lockdown, there was a reduction in sunlight exposure but conversely an increase in the time spent in front of screens that correlated with the worsening of VKC signs and symptoms in direct proportion to the hours/day of screen exposure. Our results also showed a statistically significant difference in the relative impact of long-distance learning on VKC clinical manifestations in the different Italian regions.

Pathogenesis of Olfactory Disorders in COVID-19

Since the outbreak of the SARS-CoV-2 pandemic, olfactory disorders have been reported as a frequent symptom of COVID-19; however, its pathogenesis is still debated. The aim of this review is to summarize the current understanding of the pathogenesis of smell impairment in the course of COVID-19 and to highlight potential avenues for future research on this issue. Several theories have been proposed to explain the pathogenesis of COVID-19-related anosmia, including nasal obstruction and rhinorrhea, oedema of the olfactory cleft mucosa, olfactory epithelial damage either within the olfactory receptor cells or the supporting non-neural cells (either direct or immune-mediated), damage to the olfactory bulb, and impairment of the central olfactory pathways. Although the pathogenesis of COVID-19-related anosmia is still not fully elucidated, it appears to be mainly due to sensorineural damage, with infection of the olfactory epithelium support cells via the ACE1 receptor and disruption of the OE caused by immense inflammatory reaction, and possibly with direct olfactory sensory neurons infection mediated by the NRP-1 receptor. Involvement of the higher olfactory pathways and a conductive component of olfactory disorders, as well as genetic factors, may also be considered.

Relationship between Recovery from COVID-19-Induced Smell Loss and General and Oral Health Factors

Background and Objectives: Loss of smell is one of the strongest predictors of coronavirus disease 2019 (COVID-19) and can persist long after other symptoms have resolved. “Long” cases (>28 days) of smell dysfunction present future challenges to medical and dental professionals, as there is a lack of evidence on the causes and any exacerbating or relieving factors. This study aimed to explore the persistence of COVID-19-induced smell loss and association with physical, lifestyle and oral health factors. Materials and Methods: This study was a cross-sectional survey of 235 participants. Recovery of smell was explored, comparing rapid recovery (≤28 days) with prolonged recovery (>28 days). Associative factors included age, sex, illness severity, diet, BMI, vitamin D supplementation, antidepressants, alcohol use, smoking, brushing frequency, flossing, missing teeth, appliances and number of dental restorations. Results: Smell loss showed 87% resolution within 30 days. Prolonged smell loss was significantly associated with older age (mean ± 95%, CI = 31.53 ± 1.36 years for rapid recovery vs. mean ± 95%, CI = 36.0 ± 3 years for prolonged recovery, p = 0.003) and increased self-reported illness severity (mean ± 95%, CI = 4.39 ± 0.27 for rapid recovery vs. 5.01 ± 0.54 for prolonged recovery, p = 0.016). Fisher’s exact test revealed flossing was associated with rapid recovery, with flossers comprising 75% of the rapid-recovery group, compared to 56% in the prolonged-recovery group (odds ratio ± 95%, CI = 2.26 (1.23–4.15), p = 0.01). All other factors were not significantly associated (p > 0.05). Conclusions: Increased age and illness severity were associated with prolonged smell recovery. Use of floss was the only modifiable factor associated with rapid recovery of smell loss. As 87% of cases resolve within 30 days, future studies may benefit from targeted recruitment of individuals experiencing prolonged sense loss. This would increase statistical confidence when declaring no association with the other factors assessed, avoiding type II errors.

Neurological consequences of COVID-19 and brain related pathogenic mechanisms: A new challenge for neuroscience

Due to the infection by the SARS-CoV-2 virus (COVID-19) there were also reported neurological symptoms, being the most frequent and best cited those that affect the cerebrovascular, sensorial, cognitive and motor functions, together with the neurological diffuse symptoms as for examples headache or dizziness. Besides, some of them behave high risk of mortality. Consequently, it is crucial to elucidate the mechanisms of action in brain of SARS-CoV-2 virus in order to create new therapeutic targets to fight against this new disease. Since now the mechanisms of arrival to the brain seems to be related with the following processes: blood brain barrier (BBB) disruption together with nervous or axonal transport of the virus by the trigeminal nerve, the vagus nerve, or the brain-gut-axis. Being two the mechanisms of brain affectation most cited: a direct affectation of the virus in the brain through neuroinvasion and an indirect mechanism of action due to the effects of the systemic infection. Both processes include the triggering of inflammation, hypoxia and the increased likelihood of secondary infections. This topic supposes a major novel challenge for neuroscience. Therefore, the aim of this review is to provide summarized information about the neurological symptomatology and the brain pathogenic mechanisms involved and reported in COVID-19.

Prevalence of COVID-19 in children affected by allergic rhinoconjunctivitis and asthma: results from the second "SIAIP rhinosinusitis and conjunctivitis committee" survey

BACKGROUND

The role of allergic sensitization seems to be protective against SARS CoV2 infection. The aim of this study was to evaluate, using online surveys, the impact of COVID-19 on Italian allergic children, comparing the prevalence of AR and asthma symptoms between the first and second pandemic wave.

METHODS

Both surveys were emailed to Italian pediatricians in April 2020 (first survey) and in March 2021 (second survey). The first one was related to the impact of COVID-19 and the most frequently reported symptoms. The second one was superimposed on the previous one, taking into account some additional aspects in the management of disease.

RESULTS

A total of 99 pediatricians participated in the first survey and 267 in the second one. The first survey showed that, asthma and allergic rhinoconjunctivitis prevalence was mostly between 0 and 20% throughout the country. The second survey showed a lower prevalence of both diseases nationwide in comparison to the first one. Comparing the two surveys, statistically significant differences were reported only in the distribution of asthma prevalence in Southern Italy while no differences were highlighted in the North and in the Center. Finally regarding allergic rhinoconjunctivitis prevalence, no differences were noticed nationwide.

CONCLUSIONS

Allergic rhinoconjunctivitis and asthma, if under control, did not represent risk factors for the susceptibility to SARS CoV2. Therefore, it is strongly recommended to continue therapies during COVID-19 outbreak, according to the international guidelines. However, being COVID-19 a new disease, actual knowledge will undergo continuous improvements over time.

Vitamin A in resistance to and recovery from infection: relevance to SARS-CoV2

SARS-CoV2 infects respiratory epithelial cells via its cellular receptor angiotensin-converting enzyme 2, causing a viral pneumonia with pronounced inflammation resulting in significant damage to the lungs and other organ systems, including the kidneys, though symptoms and disease severity are quite variable depending on the intensity of exposure and presence of underlying conditions that may affect the immune response. The resulting disease, coronavirus disease 2019 (COVID-19), can cause multi-organ system dysfunction in patients requiring hospitalisation and intensive care treatment. Serious infections like COVID-19 often negatively affect nutritional status, and the resulting nutritional deficiencies may increase disease severity and impair recovery. One example is the viral infection measles, where associated vitamin A (VA) deficiency increases disease severity and appropriately timed supplementation during recovery reduces mortality and hastens recovery. VA may play a similar role in COVID-19. First, VA is important in maintaining innate and adaptive immunity to promote clearance of a primary infection as well as minimise risks from secondary infections. Second, VA plays a unique role in the respiratory tract, minimising damaging inflammation, supporting repair of respiratory epithelium and preventing fibrosis. Third, VA deficiency may develop during COVID-19 due to specific effects on lung and liver stores caused by inflammation and impaired kidney function, suggesting that supplements may be needed to restore adequate status. Fourth, VA supplementation may counteract adverse effects of SARS-CoV2 on the angiotensin system as well as minimises adverse effects of some COVID-19 therapies. Evaluating interactions of SARS-CoV2 infection with VA metabolism may thus provide improved COVID-19 therapy.

COVID-19 outcomes among pregnant and nonpregnant women at reproductive age in Egypt

BACKGROUND

To describe demographic, clinical and epidemiological characteristics of pregnant and nonpregnant women with confirmed COVID-19 at reproductive age and determine risk factors of COVID-19 severe outcomes during pregnancy.

METHODS

A retrospective study for females aged 18-49 with confirmed COVID-19 by RT-PCR in Egypt, February-July 2020. Data were obtained from Egypt National Surveillance, bivariate and multivariate analysis for demographic and clinical characteristics and outcomes of COVID-19 between pregnant and nonpregnant women including ICU admission, need for ventilator and death was performed.

RESULTS

A total of 23 095 females were identified, with mean (SD) age of 35.1 (8.1) year. Of those, 408 (1.8%) were pregnant, with mean (SD) age of 29.3 (8.1) years. Compared to nonpregnant, pregnant patients were more likely to be admitted to hospital (OR = 1.7 CI = 1.4-2.1), ICU (OR = 2.4, CI = 1.3-4.3), need ventilator (OR = 3.9, CI = 2.1-7.4) and have severe outcome (OR = 3.0, CI = 1.9-4.7). Factors associated with severe outcome included: pregnancy, age > 30 years, underlying medical conditions, and living in rural areas.

CONCLUSION

Pregnant women with COVID-19 are at higher risk of severe symptoms and outcome including ICU admission, requiring ventilator and death. To reduce risk of severe outcome, counseling about for seeking medical care and health education about COVID-19 preventive measures should be performed.

The reorganisation of nutritional assessment and care in a hospital that became a COVID centre during the COVID-19 pandemic

In the early months of 2020, Europe was confronted by a pandemic that originated in China, which initially affected its territories in different ways. Parts of northern Italy were among the regions most affected. At the same time, Ticino, a small canton of Switzerland geographically wedged into Italian territory, had an incidence rate comparable to that of hard-hit Lombardy. Home to 350,000 inhabitants and separated from the rest of Switzerland by the Alps, Ticino had to face the first part of the pandemic with little available knowledge. The cantonal authorities decided to transform two active hospitals into COVID centres, concentrating all coronavirus patients there. Since the virus was new and there were no clear guidelines for managing it, the nutritional team on site had to reorganise to provide patient care, adapting their strategy to accommodate the evolution of the pandemic and growing medical knowledge. This paper explains how one of these teams developed a model to deal with the first wave of COVID, maintaining it during the second and current third wave of the pandemic.

Prediction of severe adverse events, modes of action and drug treatments for COVID-19's complications

Following SARS-CoV-2 infection, some COVID-19 patients experience severe host driven adverse events. To treat these complications, their underlying etiology and drug treatments must be identified. Thus, a novel AI methodology MOATAI-VIR, which predicts disease-protein-pathway relationships and repurposed FDA-approved drugs to treat COVID-19's clinical manifestations was developed. SARS-CoV-2 interacting human proteins and GWAS identified respiratory failure genes provide the input from which the mode-of-action (MOA) proteins/pathways of the resulting disease comorbidities are predicted. These comorbidities are then mapped to their clinical manifestations. To assess each manifestation's molecular basis, their prioritized shared proteins were subject to global pathway analysis. Next, the molecular features associated with hallmark COVID-19 phenotypes, e.g. unusual neurological symptoms, cytokine storms, and blood clots were explored. In practice, 24/26 of the major clinical manifestations are successfully predicted. Three major uncharacterized manifestation categories including neoplasms are also found. The prevalence of neoplasms suggests that SARS-CoV-2 might be an oncovirus due to shared molecular mechanisms between oncogenesis and viral replication. Then, repurposed FDA-approved drugs that might treat COVID-19's clinical manifestations are predicted by virtual ligand screening of the most frequent comorbid protein targets. These drugs might help treat both COVID-19's severe adverse events and lesser ones such as loss of taste/smell.

Post-acute COVID-19 syndrome (PCS) and health-related quality of life (HRQoL)-A systematic review and meta-analysis

There is an established literature on the symptoms and complications of COVID‐19 but the after‐effects of COVID‐19 are not well understood with few studies reporting persistent symptoms and quality of life. We aim to evaluate the pooled prevalence of poor quality of life in post‐acute COVID‐19 syndrome (PCS) and conducted meta‐regression to evaluate the effects of persistent symptoms and intensive care unit (ICU) admission on the poor quality of life. We extracted data from observational studies describing persistent symptoms and quality of life in post‐COVID‐19 patients from March 10, 2020, to March 10, 2021, following PRISMA guidelines with a consensus of two independent reviewers. We calculated the pooled prevalence with 95% confidence interval (CI) and created forest plots using random‐effects models. A total of 12 studies with 4828 PCS patients were included. We found that amongst PCS patients, the pooled prevalence of poor quality of life (EQ‐VAS) was (59%; 95% CI: 42%–75%). Based on individual factors in the EQ‐5D‐5L questionnaire, the prevalence of mobility was (36, 10–67), personal care (8, 1–21), usual quality (28, 2–65), pain/discomfort (42, 28–55), and anxiety/depression (38, 19–58). The prevalence of persistent symptoms was fatigue (64, 54–73), dyspnea (39.5, 20–60), anosmia (20, 15–24), arthralgia (24.3, 14–36), headache (21, 3–47), sleep disturbances (47, 7–89), and mental health (14.5, 4–29). Meta‐regression analysis showed the poor quality of life was significantly higher among post‐COVID‐19 patients with ICU admission (p = 0.004) and fatigue (p = 0.0015). Our study concludes that PCS is associated with poor quality of life, persistent symptoms including fatigue, dyspnea, anosmia, sleep disturbances, and worse mental health. This suggests that we need more research on PCS patients to understand the risk factors causing it and eventually leading to poor quality of life.

The Impact of the COVID-19 Epidemic During the Lockdown on Children With the Pediatric Acute-Onset Neuropsychiatric Syndrome (PANDAS/PANS): The Importance of Environmental Factors on Clinical Conditions

Introduction: In March 2020, SARS-CoV-2 declared a pandemic by the World Health Organization. Restrictive isolation measures have also brought psychological distress to the pediatric population. Building on the syndrome's characteristics, the present study explored the impact of lockdown on the clinical course of young people with PANDAS/PANS. The initial hypothesis considered both the reduced exposure to viral agents and the strategies of the parents and other containment actions as protective factors against the worsening of symptoms. Methods: One hundred and eight children, adolescents, and young adults were recruited according to the multicenter PANDAS/PANS research program. Parents participated in a web-based survey. Results: contrary to our hypothesis, the study results show an increase in symptoms during the block in 71% of the sample. Psychometric analyzes allowed us to exclude a relationship between the main symptoms of PANDAS and the increase in symptoms or the presence of symptoms before the block and their increase over time. The increase in symptoms is best explained by the presence of sleep disturbances and emotional lability. The exacerbation also appears to be linked to the onset of new symptoms in children and adolescents with depressed moods and eating problems. Furthermore, irritability and oppositionality are significant predictors of acute exacerbation. Equally statistically significant is the factor linked to the effects of pandemic stress, such as the fear of contracting the virus. No significant associations for symptom reduction have been identified between parental strategies or other parent-initiated actions, but the study demonstrates that caregiver perceived efficacy on the strategies used can reduce the risk of exacerbation. Conclusion: This preliminary study highlights the importance of studying the causes of increased symptoms in children with PANDAS/PANS. Life events can exacerbate the clinical condition or generate new symptoms in young patients. In particular, environmental, family, and social changes in the course of clinical symptoms in PANDAS/PANS patients should be investigated. It highlights the importance of emotional and behavioral management, which can be improved by enhancing coping strategies in young people with PANDAS/PANS and their caregivers through a combination treatment in which CBT and PMT are included, in line with guidelines. Limits: An experimental proxy-report questionnaire not yet standardized and validated on the PANS/PANDAS pediatric clinical sample was used for the exploratory study. There is also a small sample size (N = 108) and the absence of a control group (pre-lockdown or children without PANDAS/PANS). It would be interesting to evaluate the exact long-term dimensions to see the course of symptoms after covid and conduct a new study focusing on the impact of stressful events on the clinical course of the syndrome.

The prevalence of olfactory and gustatory dysfunction in covid-19 - A systematic review

OBJECTIVES

Loss of smell or taste are early symptoms of COVID-19. Given the high asymptomatic rate of COVID-19, as well as unreliable temperature checking and contact history taking, it is important to understand the role of olfactory and gustatory dysfunction (OGD) in the diagnosis of COVID-19. The aim of this study is to determine how initial symptoms of OGD can be used to screen patients for COVID-19 laboratory testing.

METHODS

We followed recommendations from the Preferred Reporting Items for Systemic Reviews and Meta-analysis (PRISMA) statement to conduct this systematic review study. We used OGD-related key words to search for literature published between January 1, 2020 and September 30, 2020 on Pubmed, Ovid Medline databases. We estimated the prevalence of OGD and compared it with that of other OGD-related symptoms. The weighted summary proportion under the fixed and random effects model was assessed using MedCalc statistical software. Whenever there was heterogeneity, a random effects model was selected. Publication bias was assessed by funnel plot asymmetry and Egger's regression test.

RESULTS

A total of 25 articles (evidence level III:5; IV:20) were identified and reviewed. Data synthesis of 19 articles revealed that the pooled prevalence of olfactory dysfunction in COVID-19 is 53.56% (range 5.6-100%, 95% CI 40.25-66.61%). The pooled prevalence of gustatory dysfunction in COVID-19 is 43.93% (range 1.5-85.18%, 95% CI 28.72-59.74%), just behind fever (62.22%, range 18.18-95.83%, 95% CI 54.82-69.33%), cough (64.74%, range 38.89-87.5%, 95% CI 57.97-71.22%), and fatigue (56.74%, range 6.25-93.62%, 95% CI 32.53-79.35%). The prevalence of gustatory dysfunction in subgroup with objective evaluation is lower than those without (9.91% vs. 49.21%, relive risk 2.82, p<0.001).

CONCLUSION

Our updated systematic review attests that OGD is an important early symptom of COVID-19 infection. Screening for OGD should be further emphasized to prioritize patients for laboratory test.

Olfactory and taste dysfunctions in COVID-19

PURPOSE OF REVIEW

Olfactory dysfunction (OD) can be a single and early prominent symptom of severe acute respiratory syndrome (SARS)-COV-2 infection unlike middle east respiratory syndrome (MERS) and SARS. OD data are very informative but many are not peer-reviewed, often inconclusive and may reveal variable and sometimes contradictory results. This is often due to incongruent data of subjective and objective OD testing. Mechanistic pathways of OD and taste dysfunction (TD) are slowly unveiling, not infrequently extrapolated from historical models of SARS and MERS and are still partly unclear.

RECENT FINDINGS

We reviewed the literature on OD and TD during the COVID-19 pandemic analyzing current data on pathogenesis and clinical correlates including prevalence, recovery rates, risk factors, and predictive power. Also, we evaluated various methods of subjective and objective olfactory testing and discussed challenges in management of patients with OD and rhinitis during the pandemic.

SUMMARY

Subjective evaluation of smell disturbances during COVID-19 pandemic likely underestimates true prevalence, severity, and recovery rates of OD when compared to objective testing. OD is predictive of COVID-19 infection, more so when associated with TD. Recognizing inherent limitations of both subjective and objective OD and TD testing enables us better to manage chemosensory dysfunction in COVID-19 patients. Besides, current mechanistic data suggest neurotropism of COVID-19 for olfactory neuro-epithelium and a potential role of transient receptor potential (TRP) channels. Future studies are needed to explore further the neurogenic inflammation in COVID-19.

Updates on Children with Allergic Rhinitis and Asthma during the COVID-19 Outbreak

BACKGROUND

During the lockdown period caused by the SARS-CoV-2 pandemic, we monitored via online survey the trend of allergic symptoms and the therapeutic compliance in patients followed at our center.

MATERIAL AND METHODS

In June 2020, we selected children followed at the Allergy and Immunology Service of Umberto I Hospital, aged between 6 and 16 years old, diagnosed with asthma and/or rhinitis and sensitized to grass pollen or dust mite. We sent an email with 12 multiple-choice questions investigating several areas: type of disease and sensitization, recurrence of symptoms, medication use during lockdown compared to the same period of the previous year.

RESULTS

The results of 82 questionnaires showed that 17.8% of patients suffered from asthma, 24.4% from rhinitis, and 57.8% from both. Within the group of asthmatic children, most of them presented an improvement of their symptoms. Likewise, with regard to allergic rhinitis, most of them reported better clinical conditions. Regarding treatment, we observed a global decrease in the use of on-demand therapies (salbutamol, nasal corticosteroid, and antihistamine) for both pathologies. In addition, there was a reduction in the use of basal therapy for asthma and rhinitis from 2019 (23.3%) to 2020 (15.5%).

CONCLUSIONS

Our data show a general trend of clinical improvement and a reduction in the use of on-demand and basal therapy in allergic children during the lockdown.

COVID-19 and Parkinson's disease: Defects in neurogenesis as the potential cause of olfactory system impairments and anosmia

Anosmia, a neuropathogenic condition of loss of smell, has been recognized as a key pathogenic hallmark of the current pandemic SARS-CoV-2 infection responsible for COVID-19. While the anosmia resulting from olfactory bulb (OB) pathology is the prominent clinical characteristic of Parkinson's disease (PD), SARS-CoV-2 infection has been predicted as a potential risk factor for developing Parkinsonism-related symptoms in a significant portion of COVID-19 patients and survivors. SARS-CoV-2 infection appears to alter the dopamine system and induce the loss of dopaminergic neurons that have been known to be the cause of PD. However, the underlying biological basis of anosmia and the potential link between COVID-19 and PD remains obscure. Ample experimental studies in rodents suggest that the occurrence of neural stem cell (NSC) mediated neurogenesis in the olfactory epithelium (OE) and OB is important for olfaction. Though the occurrence of neurogenesis in the human forebrain has been a subject of debate, considerable experimental evidence strongly supports the incidence of neurogenesis in the human OB in adulthood. To note, various viral infections and neuropathogenic conditions including PD with olfactory dysfunctions have been characterized by impaired neurogenesis in OB and OE. Therefore, this article describes and examines the recent reports on SARS-CoV-2 mediated OB dysfunctions and defects in the dopaminergic system responsible for PD. Further, the article emphasizes that COVID-19 and PD associated anosmia could result from the regenerative failure in the replenishment of the dopaminergic neurons in OB and olfactory sensory neurons in OE.

Elucidating the Neuropathologic Mechanisms of SARS-CoV-2 Infection

The current pandemic caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a public health emergency. To date, March 1, 2021, coronavirus disease 2019 (COVID-19) has caused about 114 million accumulated cases and 2.53 million deaths worldwide. Previous pieces of evidence suggest that SARS-CoV-2 may affect the central nervous system (CNS) and cause neurological symptoms in COVID-19 patients. It is also known that angiotensin-converting enzyme-2 (ACE2), the primary receptor for SARS-CoV-2 infection, is expressed in different brain areas and cell types. Thus, it is hypothesized that infection by this virus could generate or exacerbate neuropathological alterations. However, the molecular mechanisms that link COVID-19 disease and nerve damage are unclear. In this review, we describe the routes of SARS-CoV-2 invasion into the central nervous system. We also analyze the neuropathologic mechanisms underlying this viral infection, and their potential relationship with the neurological manifestations described in patients with COVID-19, and the appearance or exacerbation of some neurodegenerative diseases.

Chemosensory Dysfunctions Induced by COVID-19 Can Persist up to 7 Months: A Study of Over 700 Healthcare Workers

Several studies have revealed either self-reported chemosensory alterations in large groups or objective quantified chemosensory impairments in smaller populations of patients diagnosed with COVID-19. However, due to the great variability in published results regarding COVID-19-induced chemosensory impairments and their follow-up, prognosis for chemosensory functions in patients with such complaints remains unclear. Our objective is to describe the various chemosensory alterations associated with COVID-19 and their prevalence and evolution after infection. A cross-sectional study of 704 healthcare workers with a RT–PCR-confirmed SARS-CoV-2 infection between 2020 February 28 and 2020 June 14 was conducted 3–7 months after onset of symptoms. Data were collected with an online questionnaire. Outcomes included differences in reported chemosensory self-assessment of olfactory, gustatory, and trigeminal functions across time points and Chemosensory Perception Test scores from an easy-to-use at-home self-administered chemosensory test. Among the 704 participants, 593 (84.2%) were women, the mean (SD) age was 42 (12) years, and the questionnaire was answered on average 4.8 (0.8) months after COVID-19. During COVID-19, a decrease in olfactory, gustatory, and trigeminal sensitivities was reported by 81.3%, 81.5%, and 48.0%, respectively. Three to 7 months later, reduced sensitivity was still reported by 52.0%, 41.9%, and 23.3%, respectively. Chemosensory Perception Test scores indicate that 19.5% of participants had objective olfactory impairment. These data suggest a significant proportion of COVID-19 cases have persistent chemosensory impairments at 3–7 months after their infection, but the majority of those who had completely lost their olfactory, gustatory, and trigeminal sensitivities have improved.

The importance of smell and taste in everyday life: Dysfunction in COVID-19 patients

Human-to-human transmission of coronavirus (SARS-CoV-2) - COVID-19 (corona virus disease 2019) - is characterized by a pandemic exponential rate and the patients with mild to moderate infection have odor and taste problems that represent a new atypical disease. A new viral syndrome of acute anosmia or "new loss of taste or smell" without rhinitis and nasal obstruction or rhinorrhea has been placed on the list of symptoms that may occur 2 to 14 days after exposure to the COVID-19 virus. Two months after declaring the COVID-19 pandemic in May 2020, the World Health Organization (WHO) has recognized changes in the perception of smell and taste as symptoms of this disease. The described cardinal symptoms are more common in the population of young patients and able-bodied people which facilitates the spread of disease. Significantly higher prevalence of patients with COVID-19 who have lost their taste and smell is treated at home (rare hospitalization), lung damage is rare, as well as oxygen therapy with mild lymphopenia. Different scenarios of SARS-CoV-2 viral infection can be assumed: it is probable that the virus does not enter directly into olfactory sensory neurons (they do not have ACE2 and TMPRSS2 receptors), but it is localized to vascular pericytes and causes inflammatory processes and vasculopathies. On the other hand, direct infection of non-neuronal cells which contain said receptors is possible. Those are specific cell types in the olfactory epithelium such as sustentacular, horizontal basal cells, as well as Bowman's glands, which leads to massive degeneration and loss of olfactory neurons. The sense of taste is a complex sensation that is the result of the interaction of smell, taste, temperature and texture of food. The virus damages cranial nerves, epithelial receptors and blood vessels leading to taste damage (ageusia or dysgeusia). A multidisciplinary approach with epidemiological, clinical and basic research is needed to elucidate the mechanism of sensorineural odor and taste loss caused by coronavirus.