Search Results (12,290)

After first appearing in December 2019, coronavirus disease 2019 (COVID-19) spread rapidly, leading to global effects and significant risks to health systems. The virus’s high replication competence in the human lung accelerated the severity of lung pneumonia cases, resulting in a catastrophic death rate. Variable observations in the clinical testing of virus-related and patient-related cases across different populations led to ambiguous results. Medical and epidemiological studies on the virus effectively use imaging and scanning devices to help explain the virus’s behavior and its impact on the lungs. Varying equipment resources and a lack of uniformity in medical imaging acquisition led to disorganized and widely dispersed data collection worldwide, while high heterogeneity in datasets caused a poor understanding of the virus and related strains, consequently leading to unstable results that could not be generalized. Hospitals and medical institutions, therefore, urgently need to collaborate to share and extract useful knowledge from these COVID-19 datasets while preserving the privacy of medical records. Researchers are turning to an emerging technology that enhances the reliability and accessibility of information without sharing actual patient data. Federated learning (FL) is a technique that learns distributed data locally, sharing only the weights of each local model to compute a global model, and has the potential to improve the generalization of diagnosis and treatment decisions. This study investigates the applicability of FL for COVID-19 under the impact of data heterogeneity, defining the lung imaging characteristics and identifying the practical constraints of FL in medical fields. It describes the challenges of implementation from a technical perspective, with reference to valuable research directions, and highlights the research challenges that present opportunities for further efforts to overcome the pitfalls of distributed learning performance. The primary objective of this literature review is to provide valuable insights that will aid in the formulation of effective technical strategies to mitigate the impact of data heterogeneity on the generalization of FL results, particularly in light of the ongoing and evolving COVID-19 pandemic. Full article

This report examines the evolving role of coronavirus disease 2019 (COVID-19) vaccination in Japan, especially in light of the reduced public concern following the reclassification of COVID-19 as a Category 5 infectious disease in May 2023. With over half the population estimated to have hybrid immunity from prior infections and vaccinations, this report evaluated the necessity and frequency of additional booster doses. Despite strong recommendations from Japanese medical societies to continue vaccination, public skepticism remains owing to financial burdens, adverse reactions, and the perceived limited benefits of frequent boosters. Studies on antibody responses have revealed that individuals with hybrid immunity maintain robust protection with significantly elevated antibody titers that persist over extended periods. Case studies have indicated durable immunity among individuals who have both been vaccinated and experienced breakthrough infections, raising questions about the need for uniform booster policies. This report also discusses the newly approved replicon-type (self-amplifying) vaccines currently available only in Japan, which have generated public and professional debates regarding their efficacy and safety. A more personalized approach to vaccination that takes into account the antibody titers, prior infection history, and individual choices is recommended. Finally, this report underscores the importance of aligning vaccination policies with scientific evidence and public sentiment to optimize COVID-19 countermeasures in Japan. Full article

Antibody-dependent enhancement (ADE) is a phenomenon in which antibodies enhance subsequent viral infections rather than preventing them. Sub-optimal levels of neutralizing antibodies in individuals infected with dengue virus are known to be associated with severe disease upon reinfection with a different dengue virus serotype. For Severe Acute Respiratory Syndrome Coronavirus type-2 infection, three types of ADE have been proposed: (1) Fc receptor-dependent ADE of infection in cells expressing Fc receptors, such as macrophages by anti-spike antibodies, (2) Fc receptor-independent ADE of infection in epithelial cells by anti-spike antibodies, and (3) Fc receptor-dependent ADE of cytokine production in cells expressing Fc receptors, such as macrophages by anti-nucleocapsid antibodies. This review focuses on the Fc receptor-dependent ADE of cytokine production induced by anti-nucleocapsid antibodies, examining its potential role in severe COVID-19 during reinfection and its contribution to the post-acute sequelae of COVID-19, i.e., prolonged symptoms lasting at least three months after the acute phase of the disease. We also discuss the protective effects of recently identified anti-spike antibodies that neutralize Omicron variants. Full article

The COVID-19 pandemic has significantly impacted healthcare systems worldwide, including dental care. This study aimed to investigate the effects of the pandemic on the management of medication-related osteonecrosis of the jaw (MRONJ). Abnormal blood glucose levels may contribute to the development of MRONJ and act as an important risk factor. This retrospective study included 217 patients with MRONJ. The patients were divided into two groups: the pre-COVID-19 group (16 March 2018 to 16 March 2020; 75 patients; 46 females and 29 males; average age, 74.5 years) and the post-COVID-19 group (1 June 2022 to 1 June 2024; 142 patients; 91 females and 51 males; average age, 69.6 years). Data pertaining to demographic characteristics, length of hospital stay, glucose levels, location of lesions, and underlying diseases were collected. The average length of hospital stays was 4 and 5 days in the pre- and post-COVID-19 groups, respectively. The average fasting glucose levels were 5.5 and 5.9 mmol/L in the pre- and post-COVID-19 groups, respectively. Localization patterns shifted, with a higher incidence in the maxilla in the post-COVID-19 group. These findings suggest a significant increase in MRONJ cases and changes in clinical outcomes due to the pandemic. The increase in the number of patients treated after the pandemic highlights the importance of ongoing vigilance and adaptation in preventing MRONJ, with a particular focus on risk factors. Full article

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in young children. During the COVID-19 pandemic, a significant change in the epidemiology of RSV and other viruses occurred worldwide, leading to a reduction in the circulation of these infectious agents. After the pandemic, the resurgence of seasonal respiratory viruses occurred, but some features of these infections contrast to those registered prior to the pandemic. In the present work, we studied 390 children <5 years old admitted to the hospital to determine the contribution of RSV, SARS-CoV-2, human metapneumovirus (hMPV), and influenza viruses to acute respiratory infections during the 2023–2024 winter season in Mexico. RSV was the most frequently detected virus (n = 160, 41%), followed by SARS-CoV-2 (n = 69, 17.7%), hMPV (n = 68, 17.4%), and influenza A or B (n = 40, 10.26%). Fourteen patients required admission to the intensive care unit, including six (42.8%) with RSV infection. Four children died (1%). At least one of the four viruses was detected in all deceased patients: SARS-CoV-2 in one; SARS-CoV-2 and hMPV in two; and RSV, influenza A, and SARS-CoV-2 in one. The high impact of RSV and other respiratory viruses indicates the need to implement specific preventive programs to reduce the morbidity and mortality associated with them. Full article

In 2020, the coronavirus disease 2019 (COVID-19) pandemic began worldwide. We examined the association between dental visit status and the incidence of COVID-19 and hospitalisation for it among older people based on medical claims data to help reduce COVID-19 severity. The study included 170,232 people who were 75–85 years old in fiscal 2019, with fiscal 2020 and 2021 serving as the follow-up period to ascertain the status of COVID-19. Using medical claims data, we investigated four types of dental visit (no visit, only periodontal treatment, periodontal and other treatment, and only other treatment) during fiscal 2019 and the incidence of COVID-19 and hospitalisation for COVID-19 during the follow-up period. Logistic regression analyses were performed with the incidence of COVID-19 and hospitalisation for COVID-19 as the dependent variables. Of the participants, 3206 (1.9%) developed COVID-19, of whom, 559 (17.4%) were hospitalised. There was not a significant association between the incidence of COVID-19 and type of dental visit. Participants with dental visits for periodontal treatment during the baseline year had a significantly lower odds ratio (OR) for hospitalisation due to COVID-19 compared to those without dental visits (OR: 0.71, 95% confidence interval: 0.58–0.78). The results suggest that dental visits for periodontal treatment including maintenance are important not only for maintaining oral health but also for preventing severe COVID-19. Full article

Background/Objectives: Healthcare professionals (HCPs) hold significant influence over public attitudes toward vaccinations. Studies suggest that HCPs are hesitant towards the coronavirus disease 2019 (COVID-19) vaccines. This hesitancy could lead to lower vaccination rates in the community. Therefore, this scoping review aimed to assess the extent of hesitancy towards COVID-19 booster doses among HCPs and identify the associated factors. Methods: A comprehensive search was conducted in the PubMed and Scopus databases from April to August 2024, using keywords related to COVID-19, vaccine hesitancy, HCPs, and booster vaccination. Studies that had been peer-reviewed, published in English after 2022, and focused on the hesitancy of the COVID-19 booster dose hesitancy among HCPs were included. Out of the 6703 studies screened, 24 studies were included. Results: Most of the HCPs have received their initial series of COVID-19 vaccinations. However, there is a lower rate of uptake for booster doses, with hesitancy rates ranging from 12% to 66.5%. Hesitancy rates varied significantly across continents, with Asia, Africa, and Europe ranging from 19.7% to 66.5%, 27% to 46.1%, 14% to 60.2%, respectively. Hesitancy was reported to be influenced by various factors, including concerns about vaccine safety, necessity, and effectiveness of these vaccines. In addition, the hesitancy regarding booster doses was also found to be influenced by factors like age, gender, profession, and previous COVID-19. Physicians, nurses, and pharmacists exhibited vaccine hesitancy rates ranging from 12.8% to 43.7%, 26% to 37%, and 26% to 34.6%, respectively. Conclusions: Our review underscores the hesitancy among HCPs towards receiving booster doses across countries around the world and explores the underlying factors. These findings provide valuable insights for the design of future pandemic vaccination programs. Full article

Coronavirus disease 19 (COVID-19) is responsible for one of the worst pandemics in human history. The causative virus, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), can invade host cells in multiple organs by binding the angiotensin-converting enzyme (ACE) II expressed on the cell surface. Once inside the host cell, viral replication takes place, leading to cellular disruption and the release of signal molecules that are recognised by the innate immune system. Innate immunity activation leads to the release of proinflammatory cytokines and primes the adaptive immune system. The proinflammatory environment defends against further viral entry and replication. SARS-CoV-2 infection is thought to lead to myocardial injury through several mechanisms. Firstly, direct viral-mediated cellular invasion of cardiomyocytes has been shown in in vitro and histological studies, which is related to cellular injury. Secondly, the proinflammatory state during COVID-19 can lead to myocardial injury and the release of protein remnants of the cardiac contractile machinery. Thirdly, the hypercoagulable state of COVID-19 is associated with thromboembolism of coronary arteries and/or other vascular systems. COVID-19 patients can also develop heart failure; however, the underlying mechanism is much less well-characterised than for myocardial injury. Several questions remain regarding COVID-19-related heart failure, including its potential reversibility, the role of anti-viral medications in its prevention, and the mechanisms underlying heart failure pathogenesis in long COVID-19. Further work is required to improve our understanding of the mechanism of cardiac sequelae in COVID-19, which may enable us to target SARS-CoV-2 and protect patients against longer-lasting cardiovascular complications. Full article

Disease prediction using computer-based methods is now an established area of research. The importance of technological intervention is necessary for the better management of disease, as well as to optimize use of limited resources. Various AI-based methods for disease prediction have been documented in the literature. Validated AI-based systems support diagnoses and decision making by doctors/medical practitioners. The resource-efficient dissemination of the symptoms identified and the diagnoses undertaken is the requirement of the present-day scenario to support paperless, yet seamless, information sharing. The representation of symptoms using grammar provides a novel way for the resource-efficient encoding of disease diagnoses. Initially, symptoms are represented as strings, and, in terms of grammar, this is called a sentence. Moreover, the conversion of the generated string containing the symptoms and the diagnostic outcome to a QR code post encryption makes it portable. The code can be stored in a mobile application, in a secure manner, and can be scanned wherever required, universally. The patient can carry the medical condition and the diagnosis in the form of the QR code for medical consultations. This research work presents a case study based on two diseases, influenza and coronavirus, to highlight the proposed methodology. Both diseases have some common and overlapping symptoms. The proposed system can be implemented for any kind of disease detection, including clinical and diagnostic imaging. Full article

Nasal spray treatments that inhibit the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) entry into nose and nasopharynx at early stages can be an appropriate approach to stop or delay the progression of the disease. We performed a prospective, randomized, double-blind, placebo-controlled, parallel-group, multicentric, phase II clinical trial comparing the rate of hospitalization due to COVID-19 infection between azelastine 0.1% nasal spray and placebo nasal spray treatment groups. The study furthermore assessed the reduction in virus load in SARS-CoV-2-infected subjects estimated via quantitative reverse transcriptase polymerase chain reaction (RT-PCR) using nasopharyngeal swabs in both groups during the treatment period. A total of 294 subjects with mild COVID-19 infection were screened and randomized in a 1:1 ratio. There was no incidence of COVID-19-related hospitalization in either treatment group. Mean virus load was significantly reduced in both groups during the 11 treatment days as compared with baseline viral load values. The reduction in virus load in the azelastine 0.1% nasal spray group was significantly higher than the reduction in the placebo group at day 11 (log₁₀ 5.93 vs. log₁₀ 5.85 copies/mL, respectively, p = 0.0041). A total of 39 (32.0%) subjects in the azelastine 0.1% treatment group and 40 (31.0%) subjects in the placebo group reported 48 and 51 adverse events, respectively. It is therefore concluded that azelastine 0.1% nasal spray is an efficacious, safe, and well-tolerated treatment of mild COVID-19 infection. Full article

Background/objectives: Coronavirus-19 (COVID-19) vaccines represent a significant milestone in the fight against coronavirus disease. Ongoing post-marketing surveillance and research are crucial for ensuring vaccine safety and effectiveness, aiding public health planning. Methods: Our retrospective cohort study included Albertans five years and older and vaccinated with at least one dose of an approved COVID-19 vaccine between 14 December 2020 and 30 April 2022. This epidemiological study aimed to determine the incidence of reported adverse events following immunization (AEFI) in Alberta and identify associated risk factors. Results: The study included 3,527,106 vaccinated Albertans who met the study inclusion criteria. A total of 2541 individuals (72.0 per 100,000) reported an AEFI, with 2759 adverse events, most of which occurred following the first dose of vaccine and within the first week post-vaccination. Of these, 70.4% were female, and the highest incidence was in the 35–54 age group. Given that mRNA vaccines were predominantly administered across Canada, we report AEFI rates (per 100,000 doses) for the mRNA vaccine brands at 27.7 for Pfizer and 40.7 for Moderna. Allergic events were the most frequently reported AEFI, followed by adenopathy. Logistic regression analysis indicated that sex (with females at higher risk), presence of comorbidities, days to symptom onset, vaccine type (mRNA vs. mixed doses), and the number of doses were significant factors associated with an AEFI event. Conclusions: Our study provides valuable information to guide policies surrounding COVID-19 vaccination. While the risk of serious adverse events was low in the population-based sample, further research is warranted to identify and investigate other possible risk factors that are still unknown. Full article

Objectives: We aim to study the relative viral load using salivary polymerase chain reaction among pregnant women treated with Paxlovid. Methods: Pregnant women with coronavirus disease 2019 were allocated to two groups: those receiving Paxlovid and those receiving no antiviral agents. We compared the nasopharyngeal and salivary relative viral loads and their changes in saliva specimens. Results: Among the thirty-seven pregnant women, seventeen received Paxlovid, and twenty received no antiviral agents. The viral cycle threshold value of saliva was significantly higher than that from nasopharynx, with a median ± interquartile range of 26.44 ± 7.68 versus 17.6 ± 9.6 in the Paxlovid group (p = 0.005). Following treatment, the median salivary viral load decreased by 13.40 cycle threshold values in the Paxlovid group (from a median of [Day 0 Ct] to [Day 4/5 Ct]), compared to a change of −1.59 cycle threshold values in the no-antiviral group (from a median of [Day 0 Ct] to [Day 4/5 Ct]) (p = 0.021). The detection rate of coronavirus disease 2019 using salivary polymerase chain reaction was 83.8% (31/37). Conclusions: This study showed that saliva is a useful diagnostic tool for coronavirus disease 2019 in pregnant women, and a significant decrease in the relative viral load of saliva was observed in those treated with Paxlovid. Full article

Background: The COVID-19 pandemic prompted unprecedented vaccine development efforts against SARS-CoV-2. India, which was one of the countries most impacted by COVID-19, developed its indigenous vaccine in addition to utilizing the ones developed by other countries. While antibody levels and neutralizing antibody titres are considered initial correlates of immune protection, long-term protection from the pathogen relies on memory B and T cells and their recall responses. In this regard, global research has primarily focused on mRNA-based vaccines. The studies on immune memory response, particularly B cell memory response induced by the vaccines given to Indians, remain relatively obscure. Methods: We assessed Receptor Binding Domain-specific memory B cells in the peripheral circulation and their ability to secrete antigen-specific antibodies among Indians vaccinated with Covaxin (BBV152), Covishield (AZD1222), Corbevax (BECOV2D), and Sputnik Light, as well as unvaccinated individuals. Results: Corbevax and Sputnik Light conferred better antibody-secreting cell (ASC) responses over time compared to other groups. Conclusions: These findings contribute to our understanding of vaccine-induced immune memory in the Indian population; providing insights that could inform future vaccine strategies. Full article

Oxidative stress plays a critical role in various physiological and pathological processes, particularly during pregnancy, where it can significantly affect maternal and fetal health. In the context of viral infections, such as those caused by Human Immunodeficiency Virus (HIV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), oxidative stress may exacerbate complications by disrupting cellular function and immune responses. Antiviral drugs, while essential in managing these infections, can also contribute to oxidative stress, potentially impacting both the mother and the developing fetus. Understanding the mechanisms by which antivirals can contribute to oxidative stress and examination of pharmacokinetic changes during pregnancy that influence drug metabolism is essential. Some research indicates that antiretroviral drugs can induce oxidative stress and mitochondrial dysfunction during pregnancy, while other studies suggest that their use is generally safe. Therefore, concerns about long-term health effects persist. This review delves into the complex interplay between oxidative stress, antioxidant defenses, and antiviral therapies, focusing on strategies to mitigate potential oxidative damage. By addressing gaps in our understanding, we highlight the importance of balancing antiviral efficacy with the risks of oxidative stress. Moreover, we advocate for further research to develop safer, more effective therapeutic approaches during pregnancy. Understanding these dynamics is essential for optimizing health outcomes for both mother and fetus in the context of viral infections during pregnancy. Full article

Background/Objectives: According to the World Health Organization, the gold standard for diagnosing COVID-19 is the Reverse Transcription Polymerase Chain Reaction (RT-PCR) test. However, to confirm the diagnosis in patients who have negative results but still show symptoms, imaging tests, especially computed tomography (CT), are used. In this study, using convolutional neural networks, we compared the following topics using manual and automatic lung segmentation methods: (1) the performance of an automatic segmentation of COVID-19 areas using two strategies for data partitioning, CT scans, and slice strategies; (2) the performance of an automatic segmentation method of COVID-19 when there was interobserver agreement between two groups of radiologists; and (3) the performance of the area affected by COVID-19. Methods: Two datasets and two deep neural network architectures are used to evaluate the automatic segmentation of lungs and COVID-19 areas. The performance of the U-Net architecture is compared with the performance of a new architecture proposed by the research group. Results: With automatic lung segmentation, the Dice metrics for the segmentation of the COVID-19 area were 73.01 ± 9.47% and 84.66 ± 5.41% for the CT-scan strategy and slice strategy, respectively. With manual lung segmentation, the Dice metrics for the automatic segmentation of COVID-19 were 74.47 ± 9.94% and 85.35 ± 5.41% for the CT-scan and the slice strategy, respectively. Conclusions: The main conclusions were as follows: COVID-19 segmentation was slightly better for the slice strategy than for the CT-scan strategy; a comparison of the performance of the automatic COVID-19 segmentation and the interobserver agreement, in a group of 7 CT scans, revealed that there was no statistically significant difference between any metric. Full article