Predisposing factors of important invasive fungal coinfections in COVID-19 patients: a review article

Detection of foodborne pathogens in contaminated food using nanomaterial-based electrochemical biosensors

Foodborne pathogens are a grave concern for the for food, medical, environmental, and economic sectors. Their ease of transmission and resistance to treatments, such as antimicrobial agents, make them an important challenge. Food tainted with these pathogens is swiftly rejected, and if ingested, can result in severe illnesses and even fatalities. This review provides and overview of the current status of various pathogens and their metabolites transmitted through food. Despite a plethora of studies on treatments to eradicate and inhibit these pathogens, their indiscriminate use can compromise the sensory properties of food and lead to contamination. Therefore, the study of detection methods such as electrochemical biosensors has been proposed, which are devices with advantages such as simplicity, fast response, and sensitivity. However, these biosensors may also present some limitations. In this regard, it has been reported that nanomaterials with high conductivity, surface-to-volume ratio, and robustness have been observed to improve the detection of foodborne pathogens or their metabolites. Therefore, in this work, we analyze the detection of pathogens transmitted through food and their metabolites using electrochemical biosensors based on nanomaterials.

Severe mold fungal infections in critically ill patients with COVID-19

The SARS-CoV-2 pandemic put an unprecedented strain on modern societies and healthcare systems. A significantly higher incidence of invasive fungal co-infections was noted compared with the pre-COVID-19 era, adding new diagnostic and therapeutic challenges in the critical care setting. In the current narrative review, we focus on invasive mold infections caused by Aspergillus and Mucor species in critically ill COVID-19 patients. We discuss up-to-date information on the incidence, pathogenesis, diagnosis and treatment of these mold-COVID-19 co-infections, as well as recommendations on preventive and prophylactic interventions. Traditional risk factors were often not recognized in COVID-19-associated aspergillosis and mucormycosis, highlighting the role of other determinant risk factors. The associated patient outcomes were worse compared with COVID-19 patients without mold co-infection.

Risk analysis of candidemia and its effect on mortality in COVID 19 and non COVID 19 patients

Background and Objectives

Candidemia is the most common serious fungal infection in critically ill patients in intensive care units (ICU). It series fourth among bloodstream infectious agents. In this study, candidemia risk analysis was examined in COVID 19 and non-COVID 19 patients during the pandemic period.

Materials and Methods

COVID 19 and non-COVID 19 cases who were followed up with candidemia in the ICU of our hospital were retrospectively screened. Demographic data, intubation, central venous catheter (CVC), medications, and total parenteral nutrition (TPN) status were evaluated in terms of risk between the two groups. Isolated Candida species and susceptibilty were evaluated.

Results

When age, gender, medication, intubation, TPN and CVC were evaluated, no difference was seen in terms of risk. Differences were detected in terms of comorbidities. While the most frequently identified Candida species was C. albicans, the most frequently detected species in the COVID19 patient group was C. parapsilosis.

Conclusion

There was no difference in candidemia incidence and risk factors between the two groups. Since candidemias were evaluated in terms of comorbidities, it was determined that Diabetes Mellitus (DM) and chronic obstructive pulmoner disease (COPD) were more common in patients with COVID 19 and less common in coronary artery disease (CAD) and malignancy.

Coronavirus disease 2019 (COVID-19)-associated brain abscesses caused by Pseudomonas aeruginosa and Aspergillus fumigatus: two case and a review of the literature

BACKGROUND

Bacterial and fungal superinfections are commonly reported in patients with coronavirus disease 2019.

CASE PRESENTATION

We report the first case of brain and intramedullary abscesses caused by Pseudomonas aeruginosa and a rare case of brain abscesses caused by Aspergillus fumigatus in two post-coronavirus disease 2019 patients. The first patient-34-year-old Iranian woman-presented with weakness of the left upper limb, headaches, and lower limb paresthesia. She had a history of undiagnosed diabetes and had received corticosteroid therapy. The second patient-45-year-old Iranian man-presented with right-sided weakness and had a history of intensive care unit admission. Both patients passed away despite appropriate medical therapy.

CONCLUSION

The immune dysregulation induced by coronavirus disease 2019 and its' treatments can predispose patients, especially immunosuppressed ones, to bacterial and fungal infections with unusual and opportunistic pathogens in the central nervous system. Pseudomonas aeruginosa and Aspergillus fumigatus should be considered as potential causes of brain infection in any coronavirus disease 2019 patient presenting with neurological symptoms and evidence of brain abscess in imaging, regardless of sinonasal involvement. These patients should get started on appropriate antimicrobial therapy as soon as possible, as any delay in diagnosis or treatment can be associated with adverse outcomes.

Xuanfei Baidu decoction in the treatment of coronavirus disease 2019 (COVID-19): Efficacy and potential mechanisms

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide and become a major global public health concern. Although novel investigational COVID-19 antiviral candidates such as the Pfizer agent PAXLOVID™, molnupiravir, baricitinib, remdesivir, and favipiravir are currently used to treat patients with COVID-19, there is still a critical need for the development of additional treatments, as the recommended therapeutic options are frequently ineffective against SARS-CoV-2. The efficacy and safety of vaccines remain uncertain, particularly with the emergence of several variants. All 10 versions of the National Health Commission's diagnosis and treatment guidelines for COVID-19 recommend using traditional Chinese medicine. Xuanfei Baidu Decoction (XFBD) is one of the "three Chinese medicines and three Chinese prescriptions" recommended for COVID-19. This review summarizes the clinical evidence and potential mechanisms of action of XFBD for COVID-19 treatment. With XFBD, patients with COVID-19 experience improved clinical symptoms, shorter hospital stay, prevention of the progression of their symptoms from mild to moderate and severe symptoms, and reduced mortality in critically ill patients. The mechanisms of action may be associated with its direct antiviral, anti-inflammatory, immunomodulatory, antioxidative, and antimicrobial properties. High-quality clinical and experimental studies are needed to further explore the clinical efficacy and underlying mechanisms of XFBD in COVID-19 treatment.

Effects of specific doses of E-beam irradiation which inactivated SARS-CoV-2 on the nutrition and quality of Atlantic salmon

The contamination of Atlantic salmon with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has impeded the development of the cold-chain food industry and posed possible risks to the population. Electron beam (E-beam) irradiation under 2, 4, 7, and 10 kGy can effectively inactivate SARS-CoV-2 in cold-chain seafood. However, there are few statistics about the quality changes of salmon exposed to these irradiation dosages. This work demonstrated that E-beam irradiation at dosages capable of killing SARS-CoV-2 induced lipid oxidation, decreased vitamin A content, and increased some amino acids and ash content. In addition, irradiation altered the textural features of salmon, such as its hardness, resilience, cohesiveness, and chewiness. The irradiation considerably affected the L*, a*, and b* values of salmon, with the L* value increasing and a*, b* values decreasing. There was no significant difference in the sensory evaluation of control and irradiated salmon. It was shown that irradiation with 2-7 kGy E-beam did not significantly degrade quality. The inactivation of SARS-CoV-2 in salmon is advised at a dose of 2 kGy.

Secondary fungal infections in SARS-CoV-2 patients: pathological whereabouts, cautionary measures, and steadfast treatments

The earliest documented COVID-19 case caused by the SARS-CoV-2 coronavirus occurred in Wuhan, China, in December 2019. Since then, several SARS-CoV-2 mutants have rapidly disseminated as exemplified by the community spread of the recent omicron variant. The disease already attained a pandemic status with ever-dwindling mortality even after two and half years of identification and considerable vaccination. Aspergillosis, candidiasis, cryptococcosis and mucormycosis are the prominent fungal infections experienced by the majority of SARS-CoV-2 high-risk patients. In its entirety, COVID-19's nexus with these fungal infections may worsen the intricacies in the already beleaguered high-risk patients, making this a topic of substantial clinical concern. Thus, thorough knowledge of the subject is necessary. This article focuses on the concomitant fungal infection(s) in COVID-19 patients, taking into account their underlying causes, the screening methods, manifested drug resistance, and long-term effects. The information and knowledge shared herein could be crucial for the management of critically ill, aged, and immunocompromised SARS-CoV-2 patients who have had secondary fungal infections (SFIs).

Perturbations of immune landscape in COVID-19 associated mucormycosis

BACKGROUND

A rise in secondary fungal infections during the COVID-19 pandemic necessitates a deeper understanding of the associated immunological perturbations.

OBJECTIVES

To evaluate the clinical and immunological characteristics observed in patients with COVID-19 associated mucormycosis (CAM) infection.

PATIENTS/ METHODS

Cases of mucormycosis with or post-COVID-19 infection were compared with cases of acute COVID-19 and convalescent COVID-19. Lymphocyte subsets, cytokines and other laboratory markers were compared between the groups.

RESULTS

The frequency of proposed risk factors for CAM was diabetes mellitus (77%), recent history of steroid use (69%) and hypoxia during COVID-19 infection (52%). Iron metabolism was dysregulated in CAM patients with low TIBC and total iron. Further, CAM was accompanied with lymphopenia with drastic reduction in B cell counts; however, plasmablasts were not altered. Further, CAM patients had low immunoglobulin levels and antibodies specific to mucor peptide did not increase in CAM suggesting dysfunction in B-cell response. There was increase in activated effector cytotoxic CD8 T cells and NK cells in CAM compared with COVID-19 infection and healthy controls. Among T helper cells, Tregs were reduced and Th-1 frequency was increased in CAM compared with COVID-19 infection. A distinct cytokine signature was evident in CAM with increase in IL-1β, IFN-γ, IL-6, IL-22, IL-17A, IL-10, IL-2, IL-8, IL-7, IL-21 and GM-CSF.

CONCLUSION

This is the first study on immunophenotyping in CAM suggesting the need for long-term monitoring of B-cell function after SARS-CoV-2 in patients with dysregulated glycaemic control and the possible benefit of therapeutic supplementation with intravenous immunoglobulins in CAM.

Co-infections in COVID-19 patients and correlation with mortality rate. Minireview

PURPOSE

The goal of our review was to gather information on the most important community-acquired and hospital-acquired co-infections among coronavirus disease 2019 (COVID-19) patients, and to examine not only the effect of these co-infections on disease outcomes but also to identify the possible risk factors that predispose COVID-19 patients to co-infections.

METHODS

Medline (PubMed) and Google Scholar were searched for relevant articles published between January 1st, 2020, and September 31st, 2021, on the topic of co-infections among COVID-19 patients.

RESULTS

Among community-acquired and hospital-acquired co-infections, bacterial and fungal co-infections are equally frequent, followed by viral co-infections that affected a relatively smaller portion of patients. Overall, co-infections were more frequent in the hospital than at the community level. Risk factors for acquiring co-infections include male gender, longer length of hospital stay, presence of supportive treatment, such as ventilation, the admission to intensive care units, the administration of medications, such as steroids or antibiotics, and certain blood parameters, such as high C-reactive protein or lymphopenia. The presence of co-infections could aggravate the COVID-19 disease severity, prolong the healing time of patients, and lead to worse disease outcomes overall.

CONCLUSION

Co-infections may increase the mortality of COVID-19 patients, especially in the hospital setting. Paying closer attention to hygiene, adhering to diagnostic and therapeutic protocols, implementing antimicrobial stewardship programs could decrease the occurrence of co-infections and lead to improved outcomes for COVID-19 patients.

Review of proposed different irradiation methods to inactivate food-processing viruses and microorganisms

Coronaviruses, which have been enveloped nonsegmented positive-sense RNA viruses, were first mentioned in the mid-1960s and can attack people as well as a wide range of animals (including mammals and birds). Three zoonotic coronaviruses have been identified as the cause of large-scale epidemics over the last two decades: Middle East respiratory syndrome (MERS), severe acute respiratory syndrome (SARS), and swine acute diarrhea syndrome (SADS). Epithelial cells in the respiratory and gastrointestinal tract are the principal targeted cells, and viral shedding occurs via these systems in diverse ways such as through fomites, air, or feces. Patients infected with the novel coronavirus (2019-nCoV) reported having visited the Wuhan seafood wholesale market shortly before disease onset. The clinical data on established 2019-nCoV cases reported so far indicate a milder disease course than that described for patients with SARS-CoV or MERS-CoV. This study aimed to review radiation inactivation of these viruses in the food industry in three sections: visible light, ionizing radiation (alpha ray, beta ray, X-ray, gamma ray, neutron, plasma, and ozone), and nonionizing radiation (microwave, ultraviolet, infrared, laser light, and radiofrequency). Due to the obvious possibility of human-to-human and animal-to-human transmission, using at least one of these three methods in food processing and packaging during coronavirus outbreaks will be critical for preventing further outbreaks at the community level.