Factors associated with death due to severe acute respiratory syndrome caused by influenza: Brazilian population study

Introduction Influenza infection is characterized by acute viral infection of high transmissibility. Worsening of the case can lead to the need for hospitalization, severe acute respiratory syndrome (SARS) and even death. Method This is a cross-sectional population-based study that used secondary database from the Brazilian Influenza Epidemiological Surveillance Information System. Only cases of adults with diagnosis of influenza by RT-PCR and case evolution recorded were included. Results We identified 2,273 adults with SARS by influenza, 343 of which had death as an outcome. The main risk factors for death were lack of hospitalization, not having cough and age, both with p<0.001. In addition, without asthma, having black skin color, not receiving flu vaccine, having brown skin color and not having a sore throat (p≤ 0.005) were risk factors too. Conclusion Factors associated with death due to SARS caused by influenza in Brazil, risk factors and protective factors to death were identified. It was evident that those who did not receive the flu vaccine presented twice the risk of unfavorable outcome, reinforcing the need to stimulate adherence to vaccination adhering and propose changes in public policies to make influenza vaccines available to the entire population, in order to prevent severe cases and unfavorable outcomes.

ORAL LESIONS ON A COVID-19 PATIENT: AN AUTOPSY STUDY TO ELUCIDATE COINFECTION

We present a case of a patient who died of complications of COVID-19. A 29-year-old woman presented multiple bleeding ulcerous lesions involving lips and inner lip mucosa. The patient was pregnant (29th week) and presented fever, diarrhea, dyspnea, nausea, dysgeusia, and anosmia in a 27-day evolution until death. The patient was admitted to the intensive care unit, submitted to mechanical ventilation and extracorporeal membrane oxygenation, developed fetal distress, and was submitted to an emergency C-section. Cause of death was a cardiogenic shock. During minimally invasive autopsy, oral lesions were identified and postmortem biopsy was performed. Clinical hypotheses were SARS-CoV-2 vs herpes virus. The histopathologic analyses revealed mononuclear inflammatory infiltrate, and keratinocytes showed no viral inclusion or cytopathic alterations. A large amount of a cuboid shaped gram-positive coccus in a tetrad packet arrangement was observed, compatible with Sarcina ventriculi. An abundant amount of Candida spp. was also observed. Samples were negative for immunohistochemistry to anti-SARS-CoV-2, herpes simplex virus, and cytomegalovirus.

SARS-CoV-2 in saliva, viremia and seroprevalence for COVID-19 surveillance at a single hematopoietic stem cell transplantation center: a prospective cohort study.

This prospective cohort study aims to analyze the surveillance of COVID-19 at a single hematopoietic stem cell transplantation (HSCT) center in Brazil, in 29 patients undergoing allogeneic HSCT and 57 healthcare workers (nurses and dentists), through viral shedding of SARS-CoV-2 in saliva and plasma and seroprevalence of anti-SARS-CoV-2 IgG. In addition, we report two cases with prolonged persistent detection of SARS-CoV-2 without seroconversion. The sample collection was performed seven times for patients and five times for healthcare workers. Only two patients tested positive for SARS-CoV-2 in their saliva and plasma samples (6.9%) without seroconversion. All healthcare workers were asymptomatic and none tested positive. Two patients (6.9%) and four nurses (8%) had positive serology. No dentists had positive viral detection or positive serology. Our results reflect a low prevalence of positive RT-PCR and seroprevalence of SARS-CoV-2 in patients and healthcare workers at a single HSCT center. Results have also corroborated how the rigorous protocols adopted in transplant centers were even more strengthened in this pandemic scenario.

Use of saliva and RT-PCR screening for SARS-CoV-2 variants of concern: Surveillance and monitoring.

Genomic surveillance has been applied since the beginning of the COVID-19 pandemic to track the spread of the virus, leading to the characterization of multiple SARS-CoV-2 variants, including variants of concern (VOC). Although sequencing is the standard method, a rapid molecular test for screening and surveillance of VOC is considered for detection. Furthermore, using alternative saliva as specimen collection facilitates the implementation of a less invasive, self-collected sample. In this study, we applied a combinatory strategy of saliva collection and reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2 VOC detection. Saliva samples from patients attending a tertiary hospital with suspected COVID-19 were collected and SARS-CoV-2 RNA was detected using SARS-CoV-2 RT-qPCR reagent kit (PerkinElmer). Positive saliva samples were screened for SARS-CoV-2 VOC with previously described RT-PCR for Alpha, Beta, and Gamma variants. Saliva samples were positive in 171 (53%) of 324 tested. A total of 108 (74%) from positive samples were also positive for VOC by RT-PCR screening. Those samples were found between January and August 2021. This approach allowed us to successfully use an alternative and complementary tool to genomic surveillance to monitor the circulation of SARS-CoV-2 VOC in the studied population.

Micro-Fourier-transform infrared reflectance spectroscopy as tool for probing IgG glycosylation in COVID-19 patients.

It has been reported that patients diagnosed with COVID-19 become critically ill primarily around the time of activation of the adaptive immune response. However the role of antibodies in the worsening of disease is not obvious. Higher titers of anti-spike immunoglobulin IgG1 associated with low fucosylation of the antibody Fc tail have been associated to excessive inflammatory response. In contrast it has been also reported that NP-, S-, RBD- specific IgA, IgG, and IgM are not associated with SARS-CoV-2 viral load, indicating that there is no obvious correlation between antibody response and viral antigen detection. In the present work the micro-Fourier-transform infrared reflectance spectroscopy (micro-FTIR) was employed to investigate blood serum samples of healthy and COVID-19-ill (mild or oligosymptomatic) individuals (82 healthcare workers volunteers in "Instituto de Infectologia Emilio Ribas", São Paulo, Brazil). The molecular-level-sensitive, multiplexing quantitative and qualitative FTIR data probed on 1 µL of dried biofluid was compared to signal-to-cutoff index of chemiluminescent immunoassays CLIA and ELISA (IgG antibodies against SARS-CoV-2). Our main result indicated that 1702-1785 [Formula: see text] spectral window (carbonyl C=O vibration) is a spectral marker of the degree of IgG glycosylation, allowing to probe distinctive sub-populations of COVID-19 patients, depending on their degree of severity. The specificity was 87.5 % while the detection rate of true positive was 100%. The computed area under the receiver operating curve was equivalent to CLIA, ELISA and other ATR-FTIR methods ([Formula: see text]). In summary, overall discrimination of healthy and COVID-19 individuals and severity prediction as well could be potentially implemented using micro-FTIR reflectance spectroscopy on blood serum samples. Considering the minimal and reagent-free sample preparation procedures combined to fast (few minutes) outcome of FTIR we can state that this technology is suitable for fast screening of immune response of individuals with COVID-19. It would be an important tool in prospective studies, helping investigate the physiology of the asymptomatic, oligosymptomatic, or severe individuals and measure the extension of infection dissemination in patients.

Saliva: an important alternative for screening and monitoring of COVID-19 in children

Abstract: The increasing number of cases of COVID-19 worldwide poses challenges to healthcare systems not only in effectively identifying individuals positive for SARS-CoV-2, but also in isolating cases to minimise contagion in early diagnosing more severe cases that will need hospitalization. Less-invasive collection methods are indispensable in a pandemic scenario as large-scale tests are necessary to understand the actual evolution of contagion in different populations, thus enabling decision-making based on scientific evidence. Saliva has been shown to be an alternative for diagnosing viral infections as this biological fluid can be easily and quickly collected without using specific devices and causing less discomfort during collection, which is an important factor for use in children. Despite the smaller percentage of severe cases of COVID-19 among children, they seem to play an important role in the contagion as they have the same potential of transmission as that of adults. Knowing the evolution of COVID-19 pandemic in children is extremely important, mainly regarding the changing in rules of social distancing, such as re-opening schools and recreational activities spaces. In addition, countless cases of a severe multi-systemic inflammatory syndrome that shares clinical and laboratory features with Kawasaki's disease have been recently related to SARS-CoV-2 infections in children, adolescents and young adults. In view of this scenario, the aim of this study was to present saliva as an alternative for seeking diagnostic and prognostic markers of COVID-19 in children, including adequate sample collection techniques for different age groups.

Saliva: an important alternative for screening and monitoring of COVID-19 in children.

The increasing number of cases of COVID-19 worldwide poses challenges to healthcare systems not only in effectively identifying individuals positive for SARS-CoV-2, but also in isolating cases to minimise contagion in early diagnosing more severe cases that will need hospitalization. Less-invasive collection methods are indispensable in a pandemic scenario as large-scale tests are necessary to understand the actual evolution of contagion in different populations, thus enabling decision-making based on scientific evidence. Saliva has been shown to be an alternative for diagnosing viral infections as this biological fluid can be easily and quickly collected without using specific devices and causing less discomfort during collection, which is an important factor for use in children. Despite the smaller percentage of severe cases of COVID-19 among children, they seem to play an important role in the contagion as they have the same potential of transmission as that of adults. Knowing the evolution of COVID-19 pandemic in children is extremely important, mainly regarding the changing in rules of social distancing, such as re-opening schools and recreational activities spaces. In addition, countless cases of a severe multi-systemic inflammatory syndrome that shares clinical and laboratory features with Kawasaki's disease have been recently related to SARS-CoV-2 infections in children, adolescents and young adults. In view of this scenario, the aim of this study was to present saliva as an alternative for seeking diagnostic and prognostic markers of COVID-19 in children, including adequate sample collection techniques for different age groups.

COVID-19 salivary signature: diagnostic and research opportunities.

The COVID-19 (caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) epidemic started in Wuhan (Hubei Province, China) in mid-December 2019 and quickly spread across the world as a pandemic. As a key to tracing the disease and to implement strategies aimed at breaking the chain of disease transmission, extensive testing for SARS-CoV-2 was suggested. Although nasopharyngeal/oropharyngeal swabs are the most commonly used biological samples for SARS-CoV-2 diagnosis, they have a number of limitations related to sample collection and healthcare personnel safety. In this context, saliva is emerging as a promising alternative to nasopharyngeal/oropharyngeal swabs for COVID-19 diagnosis and monitoring. Saliva collection, being a non-invasive approach with possibility for self-collection, circumvents to a great extent the limitations associated with the use of nasopharyngeal/oropharyngeal swabs. In addition, various salivary biomarkers including the salivary metabolomics offer a high promise to be useful for better understanding of COVID-19 and possibly in the identification of patients with various degrees of severity, including asymptomatic carriers. This review summarises the clinical and scientific basis for the potential use of saliva for COVID-19 diagnosis and disease monitoring. Additionally, we discuss saliva-based biomarkers and their potential clinical and research applications related to COVID-19.