The Psychological Ability to Cope Reduced Infections During the Pandemic: A Two-Year Population-Based Study of The Determinants of 123 Million COVID-19 Test Results in Denmark (preprint)

During the COVID-19 pandemic, a key concern for authorities was to identify and activate the psychological states most likely to motivate the public to engage in protective behavior such as physical distancing and hygienic protection. While feelings of fear and threat were rampant during the pandemic, theories of health psychology have highlighted appraisals related to the ability to cope (e.g., the feeling of being able to cost-effectively adhere to government advice) and argued that coping appraisals are superior predictors of motivations to protect the self against risks. In this study, we provide a massive population-based comparison of the association between, on the one hand, threat appraisals, and coping appraisals and, on the other hand, protection against actual infection during the COVID-19 pandemic. To this end, we utilize a unique data infrastructure from Denmark that couple surveys of 8 % of the adult Danish population (N= 386.633) with the individual results of all 123 million COVID-19 tests performed in Denmark during 23 months of the COVID-19 pandemic. Overall, controlling for a comprehensive range of sociodemographic measures and employing panel data to bolster internal validity, we observe that stronger coping appraisals are consistently associated with lower individual probability of COVID-19 infection risk. We find no con-sistent evidence for a similar association for threat appraisals. Threat appraisals rather seem to index – to some extent, accurately – individual feelings of infection exposure. As appeals to fear also have unintended negative consequences (includ-ing anxiety, fatigue, and stigmatization), the findings provide strong empirical support for relying on coping-oriented public health communication in future societal crises in the domain of health and beyond.

Machine Learning for Affordable Diagnosis of SARS-COV-2 from Hematological and Biochemical Tests (preprint)

COVID-19, caused by the SARS-CoV-2 virus, has spread around the world and killed around 6.9 million people. Rapid and accurate diagnosis is essential for preventing and controlling the disease, reducing transmission and consequently saving lives. RT-PCR is the gold standard test used to detect the disease. However, the test is expensive and the result is time-consuming, which makes mass testing difficult, especially in countries with limited resources. In addition, the test has high analytical specificity and low diagnostic sensitivity, which leads to false-negative results. Several studies in the literature report the presence of hematological and biochemical alterations in infected patients and use these alterations with machine learning algorithms to help diagnose the disease. Therefore, this article presents the results obtained by different neural network architectures based on Adaptive Resonance Theory (ART) for the diagnosis of COVID-19. The study was conducted in two distinct stages: the first consisted of selecting the best ART network among several, using three open-access datasets and comparing the results with the literature. In the second stage, the chosen model was tested on a dataset containing patients from various hospitals in four countries. In addition, the model was subjected to external validation, including data from a country not present during the training and adjustment of the model, in order to validate the robustness and generalization capacity of the model. The results obtained by the ART networks in this study are promising, outperforming not only classical models, but also the deep learning models often used in the literature. Validation on data from different countries strengthens the model’s reliability and effectiveness.

SARS-CoV-2 Antigen Rapid Detection Tests: test performance during the COVID-19 pandemic and the impact of COVID-19 vaccination (preprint)

IntroductionDuring the COVID-19 pandemic, SARS-CoV-2 antigen rapid detection tests (RDTs) emerged as point-of-care diagnostics in addition to the RT-qPCR as the gold standard for SARS-CoV-2 diagnostics. Facing the course of the COVID-19 pandemic to an endemic characterised by several SARS-CoV-2 virus variants of concern (VOC) and an increasing public COVID-19 vaccination rate the aim of the study was to investigate the long-term test performance of SARS-CoV-2 RDT in large-scale, clinical screening use during and its influencing factors, above all SARS-CoV-2 VOC and COVID-19 vaccination. MethodsIn a prospective performance assessment conducted at a single centre tertiary care hospital, RDTs from three manufacturers (NADAL(R), Panbio, MEDsan(R)) were compared to RT-qPCR among individuals aged [≥] 6 month. The evaluation involved the determination of standardised viral load from oropharyngeal swabs as well as the evaluation of their influencing factors, especially the COVID-19 vaccination, for detecting SARS-CoV-2 in a clinical point-of-care environment spanning from 12 November 2020 to 30 June 2023 among patients, staff, and visitors of the hospital. ResultsAmong the 78,798 RDT/RT-qPCR tandems analysed, 2,016 (2.6%) tandems tested positive for SARS-CoV-2, with an overall sensitivity of 34.5% (95% CI 32.4-36.6%). A logistic regression revealed that typical COVID-19 symptoms significantly declined over the course of the study and throughout the COVID-19 pandemic, and that among the vaccinated, significantly fewer presented with an infection exhibiting typical symptoms. The employed lasso regression model indicated that only higher viral load and typical COVID-19 symptoms significantly increase the likelihood of a positive RDT result in the case of a SARS-CoV-2 infection directly. ConclusionOur findings indicate that only viral load and COVID-19 symptoms directly influence RDT performance while the obtained effects of COVID-19 vaccination and Omicron VOC both reducing RDT performance were mediated by these two factors. RDTs remain an adequate diagnostic tool for detecting SARS-CoV-2 in individuals showing respiratory symptoms. RDTs show promise beyond SARS-CoV-2, proving adaptable for detecting other pathogens like Influenza and RSV, highlighting their ongoing importance in infection control and prevention efforts.

Can self-testing be enhanced to hasten safe return of healthcare workers in pandemics? Random order, open label trial using two manufacturers' SARS-CoV-2 lateral flow devices concurrently (preprint)

ObjectivesTo inform management of competing risks from Covid-19 and key-worker absence, we evaluated whether using two manufacturers lateral flow tests (LFTs) concurrently improved SARS-CoV-2 Omicron detection and was acceptable to hospital staff. In a nested study, to understand the risks of return to work after a fixed number of days of isolation or quarantine, we examined virus culture at Days 5-7 after positive test or significant exposure. Methods and Analysis1419 fully-vaccinated Liverpool (UK) University Hospitals staff participated in a random-order, open-label trial testing whether dual LFTs improved SARS-CoV2 detection, and whether dual swabbing was acceptable to users. Main outcome was self-reported LFT result. Staff enrolled via routine testing sites for symptomatic staff and close contacts. Recruitment took place between 7th February and 8th May 2022. Participants employed nose-throat swab Innova and nose-only swab Orient Gene LFTs for 10 days, with daily LFTs taken in random order. A swab for polymerase chain reaction (PCR) analysis was taken at Day-5 and, if positive, Day-10. A questionnaire on acceptability was administered on exit. Selected participants gave swabs for viral culture on Days 5-7; swabs were delivered and returned by courier. Cultures were considered positive if cytopathic effect was apparent or the SARs-COV2 N gene sub-genomic RNA was detected by sequencing. Results226 individuals reported 1466 pairs of LFT results. Tests disagreed in 127 cases (8.7%). Orient Gene was more likely (78 cf. 49, P=0.03) to be positive. Orient Gene positive Innova negative result-pairs became more frequent over time (P<0.001). If Innova was swabbed second, it was less likely to agree with a positive Orient Gene result (P=0.005); swabbing first with Innova made no significant difference (P=0.85). Of 311 individuals completing the exit questionnaire, 90.7% reported dual swabbing was easy, 57.1% said it was no barrier to their daily routine and 65.6% preferred dual testing. Respondents had more confidence in dual c.f. single test results (median 9 cf. 8 on 10-point scale, P<0.001). Viral cultures from swabs taken at Days 5-7 were positive for 6/31 (19.4%, 7.5%-37.5%) and indeterminate for 11/31 (35.5%, 19.2%-54.6%) LFT-positive participants, indicating they were likely still infectious. ConclusionsDual brand testing increased LFT detection of SARS-CoV-2 antigen by a small but meaningful margin and was acceptable to hospital workers. Viral cultures demonstrated that policies recommending safe return to work [~]5 days after Omicron infection/exposure were flawed. Key-workers should be prepared for dynamic self-testing protocols in future pandemics. Trial registrationhttps://www.isrctn.com/ISRCTN47058442 (IRAS Project ID:311842) Key messagesO_ST_ABSWhat is already known on this topicC_ST_ABSO_LIOmicron BA.1 and BA.2 waves caused large-scale healthcare worker absence in late 2021 - early 2022, risking patient safety from both Covid-19 and reduced care capacity C_LIO_LILateral flow tests (LFTs) reliably detected SARS-CoV-2 antigen, more so with Omicron than prior variants, identifying the most infectious individuals C_LIO_LISelf-testing with LFT SARS-CoV-2 rapid antigen tests reduced Covid-19 transmission, mitigating risks of return to work, including healthcare settings C_LI What this study addsO_LIDual c.f. single brand LFT testing increased SARS-CoV-2 antigen detection marginally, but more than can be explained by extending swabbing from nose-only to nose-throat C_LIO_LINHS deployment of nose-only LFTs in response to compound pressures from Omicron, winter and pandemic burnout was safe and acceptable to most participating hospital staff C_LIO_LICulturable virus was detected confidently in a fifth (and potentially in a further third) of LFT-positive hospital workers 5-7 days after their self-referral for testing, indicating substantial protracted infectiousness C_LI How this study might affect research, practice or policyO_LIThis study shows international Covid-19 policies for return to work after fixed periods (e.g. 5 days after positive test) were flawed: too little emphasis was placed on variation in infectivity between individuals C_LIO_LIFuture pandemic preparedness needs to plan testing quality assurance unified across healthcare and community self-testing contexts, including continuous study of serial daily antigen, nucleic acid and culturable virus test results C_LI

Comparative analysis of serological assays and sero-surveillance for SARS-CoV-2 exposure in US cattle (preprint)

Coronavirus disease-2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to pose a significant threat to public health globally. Notably, SARS-CoV-2 demonstrates a unique capacity to infect various non-human animal species, documented in captive and free-living animals. However, experimental studies revealed low susceptibility of domestic cattle (Bos taurus) to ancestral B.1 lineage SARS-CoV-2 infection, with limited viral replication and seroconversion. Despite the emergence of viral variants with potentially altered host tropism, recent experimental findings indicate greater permissiveness of cattle to SARS-CoV-2 Delta variant infection compared to other variants, though with limited seroconversion and no clear evidence of transmission. While some studies detected SARS-CoV-2 antibodies in cattle in Italy and Germany, there is no evidence of natural SARS-CoV-2 infection in cattle from the United States or elsewhere. Since serological tests have inherent problems of false positives and negatives, we conducted a comprehensive assessment of multiple serological assays on over 600 cattle serum samples, including pre-pandemic and pandemic cattle sera. We found that SARS-CoV-2 pseudovirus neutralization assays with a luciferase reporter system can produce false positive results, and care must be taken to interpret serological diagnosis using these assays. We found no serological evidence of natural SARS-CoV-2 infection or transmission among cattle in the USA. Hence, it is critical to develop more reliable serological assays tailored to accurately detect SARS-CoV-2 antibodies in cattle populations and rigorously evaluate diagnostic tools. This study underscores the importance of robust evaluation when employing serological assays for SARS-CoV-2 detection in cattle populations.

Impact Of SARS-CoV-2 Pandemic On The Diagnosis Of Cervical Cancer And Precursor Lesions - A Single Center Retrospective Study (preprint)

Objective: The aim of our study was to perform a retrospective analysis of the volume of cervical screening tests, the number of patients treated with an excision method, and the incidence of invasive and non-invasive cervical during a pandemic and pre-pandemic period of 24 months. Results: There was a statistically significant age difference between the two study periods, both by the average age of patients and by age group. The mean difference was 32 years before the pan-demic and 35 years during the pandemic (p-value >0.05). The majority of patients presenting for investigations before and during the pandemic were in the 30-39-year-old age group (31.95%, respectively; 34.2% (p-value = 0.003). The biggest patient loss ratio identified by age group was in the 50–59 years: 14,53% in the pre-pandemic period and 9,1% in the pandemic period. In the pan-demic period, patients from rural areas presented in the clinical trial with a lower rate of 39.52% (83 patients) vs. 60.47% (127 patients) in urban areas. A higher percentage of patients experiencing cervicorrhagia as a clinical manifestation in the pandemic period vs. the prepandemic period, with an increase in more severe lesions in the pandemic period, has a statistical significance of 8% more newly diagnosed compared to the pre-pandemic period. Conclusion: The addressability of the patients during the COVID period was not affected in a drastic way in our study. We encountered a decrease in appointments in the age group 50–59 years and a decrease in patients with rural residence. In our study, we found an increase in cervicorrhagia as a reason for consultation in the pandemic period with a higher lesion degree, both on a pap smear and on a cervical biopsy.

Machine learning-driven COVID-19 early triage and large-scale testing strategies based on the 2021 Costa Rican Actualidades survey (preprint)

The COVID-19 pandemic underscored the importance of mass testing in mitigating the spread of the virus. This study presents mass testing strategies developed through machine learning models, which predict the risk of COVID-19 contagion based on health determinants. Using the data from the 2021 "Actualidades" survey in Costa Rica, we trained models to classify individuals by contagion risk. After theorize four possible strategies, we evaluated these using Monte Carlo simulations, analyzing the distribution functions for the number of tests, positive cases detected, tests per person, and total costs. Additionally, we introduced the metrics, efficiency and stock capacity, to assess the performance of different strategies. Our classifier achieved an AUC-ROC of 0.80 and an AUC-PR of 0.59, considering a disease prevalence of 0.26. The fourth strategy, which integrates RT-qPCR, antigen, and RT-LAMP tests, emerged as a cost-effective approach for mass testing, offering insights into scalable and adaptable testing mechanisms for pandemic response.

A Case Report of Acute Lymphoblastic Leukaemia (ALL)/Lymphoblastic Lymphoma (LBL) Following the Second Dose of Comirnaty®: An Analysis of the Potential Pathogenic Mechanism Based on of the Existing Literature (preprint)

In this report we describe the case of a healthy, young, athletic woman who developed acute lymphoblastic leukaemia (ALL)/lymphoblastic lymphoma (LBL) after receiving the second dose of the Pfizer/BioNTech modified mRNA (modRNA) COVID-19 genetic vaccine (marketed as Comirnaty®). The first dose of the genetic vaccine did not appear to illicit any noticeable side effects, but within 24 hours of the second dose the patient suffered widespread and intensifying bone pain, fever, vomiting, and general malaise. Due to the persistence of the symptoms, the patient underwent a series of tests and examinations including a full laboratory workup, a consult with a clinical immunologist and rheumatologist, a Positron Emission Tomography (PET) imaging, as well as an osteomedullary biopsy. These together led to a definitive diagnosis of ALL. A time interval of 16 weeks from the second vaccination to the diagnosis of cancer was noted. Several similar cases with identical pathology which developed after the modRNA COVID-19 vaccination, are described in case reports in the scientific literature. The massive and indiscriminate use of genetic vaccines to fight COVID-19 is raising serious concerns about their safety and about the technology platform as a whole for this purpose. Growing evidence is accumulating regarding the biodistribution and persistence of the modRNA which can reach, thanks to the lipid nanoparticles, a multitude of tissues and organs of the body, including the bone marrow and other blood-forming organs and tissues. Moreover, there is evidence that the modRNA vaccines display a particular tropism for the bone marrow, influencing the immune system at multiple levels and being able to trigger not only autoimmune-based pathologies, but also neoplastic mechanisms. The aim of this article is to assess, on the basis of the available scientific literature, the risk of developing haematopoietic cancers after modRNA vaccination, and to investigate the potential genetic mechanisms involved in the pathogenesis of disease.

Effectiveness of Autumn 2023 COVID-19 vaccination and residual protection of prior doses against hospitalisation in England, estimated using a test-negative case-control study. (preprint)

IntroductionThe last COVID-19 vaccine offered to all adults in England became available from November 2021. The most recent booster programme commenced in September 2023. Bivalent BA.4-5 or monovalent XBB.1.5 boosters were given. During the study period, the JN.1 variant became dominant in England. MethodsVaccine effectiveness against hospitalisation was estimated throughout using the test-negative case-control study design where positive PCR tests from hospitalised individuals are cases and comparable negative PCR tests are controls. Multivariable logistic regression was used to assess vaccine effectiveness against hospitalisation with the test result as the outcome, vaccination status as the primary exposure variable of interest and confounder adjustment. ResultsThere was no evidence of residual protection for boosters given as part of previous campaigns. There were 28,916 eligible tests included to estimate the effectiveness of the autumn 2023 boosters in those aged 65 years and older. VE peaked at 50.6% (95% CI: 44.2-56.3%) after 2-4 weeks, followed by waning to 13.6% (95% CI: -11.7-33.2%). Estimates were generally higher for the XBB.1.5 booster than the BA.4-5 booster, but this difference was not statistically significant. Point estimates were highest against XBB sub-lineages. Effectiveness was lower against both JN.1 and EG.5.1 variants with confidence intervals non-overlapping with the effectiveness of the XBB sub-lineages at 2-4 weeks for EG.5.1 where VE was 44.5% (95% CI: 20.2-61.4%) and at 5-9 weeks for JN.1 where VE was 26.4% (95%CI: -3.4-47.6%). ConclusionsThe recent monovalent XBB.1.5 and bivalent BA.4-5 boosters provided comparable and good protection against hospitalisation, however there was evidence of lower VE against hospitalisation of these boosters against JN.1.

CCQM-P199b: Interlaboratory comparability study of SARS-CoV-2 RNA copy number quantification (preprint)

Nucleic acid amplification tests including reverse transcription-quantitative PCR (RT-qPCR) are used to detect RNA from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of the Coronavirus disease 2019 (COVID-19) pandemic. Standardized measurements of RNA can facilitate comparable performance of laboratory tests in the absence of existing reference measurement systems early on in a pandemic. Interlaboratory study CCQM-P199b 'SARS-CoV-2 RNA copy number quantification' was designed to test the fitness-for-purpose of developed candidate reference measurement procedures (RMPs) for SARS-CoV-2 genomic targets in purified RNA materials, and was conducted under the auspices of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) to evaluate the measurement comparability of national metrology institutes (NMIs) and designated institutes (DIs), thereby supporting international standardization. Twenty-one laboratories participated in CCQM-P199b and were requested to report the RNA copy number concentration, expressed in number of copies per microliter, of the SARS-CoV-2 nucleocapsid (N) gene partial region (NC_045512.2: 28274-29239) and envelope (E) gene (NC_045512.2: 26245-26472) (optional measurement) in samples consisting of in vitro transcribed RNA or purified RNA from lentiviral constructs. Materials were provided in two categories: lower concentration (approximately 10 x 1 - 10 x 4/uL in aqueous solution containing human RNA background) and high concentration (approximately 10 x 9/uL in aqueous solution without any other RNA background). For the measurement of N gene concentration in the lower concentration study materials, the majority of laboratories (n = 17) used one-step reverse transcription-digital PCR (RT-dPCR), with three laboratories applying two-step RT-dPCR and one laboratory RT-qPCR. Sixteen laboratories submitted results for E gene concentration. Reproducibility (% CV or equivalent) for RT-dPCR ranged from 19 % to 31 %. Measurements of the high concentration study material by orthogonal methods (isotope dilution-mass spectrometry and single molecule flow cytometry) and a gravimetrically linked lower concentration material were in a good agreement, suggesting a lack of overall bias in RT-dPCR measurements. However methodological factors such as primer and probe (assay) sequences, RT-dPCR reagents and dPCR partition volume were found to be potential sources of interlaboratory variation which need to be controlled when applying this technique. This study demonstrates that the accuracy of RT-dPCR is fit-for-purpose as a RMP for viral RNA target quantification in purified RNA materials and highlights where metrological approaches such as the use of in vitro transcribed controls, orthogonal methods and measurement uncertainty evaluation can support standardization of molecular methods.

Vaccine Literacy and Hesitancy among Parents and Legal Guardians of Elementary School-Aged Children in the Midwest (preprint)

Parental refusal of childhood vaccines is a growing public health concern. Numerous reasons exist for this refusal, including religious, personal, and philosophical beliefs, and safety concerns. However, parental refusal of childhood vaccines is not simply an individualized problem for the family; this impacts herd immunity and affects the entire community. To improve vaccination rates among the pediatric population, understanding the thought process and decision-making behind parental opposition and refusal of vaccinations is essential. Using a survey developed to assess attitudes towards recommended childhood vaccines and the COVID-19 vaccine, this study examined the correlation between vaccine literacy and hesitancy among parents and legal guardians of elementary school-aged children in the Midwest. Responses were analyzed using Chi-squared tests on “R” software. Significant negative correlations were found between COVID-19 hesitancy and vaccine literacy, and resistance towards all vaccines and vaccine literacy. No significant negative correlations were found between hesitancy towards all vaccines and vaccine literacy, or hesitancy and literacy among different income and education brackets. Our results suggest that vaccine education may lessen vaccine hesitancy among parents and may be an essential factor in improving vaccination rates among the pediatric population.

Outdoor air pollution as a risk factor for testing positive for SARS-CoV-2: a nationwide test-negative case-control study in the Netherlands (preprint)

Air pollution is a known risk factor for several diseases, but the extent to which it influences COVID-19 compared to other respiratory diseases remains unclear. We performed a test-negative case-control study among people with COVID-19-compatible symptoms who were tested for SARS-CoV-2 infection, to assess whether their long- and short-term exposure to ambient air pollution (AAP) was associated with testing positive (vs. negative) for SARS-CoV-2. We used individual-level data for all adult residents in the Netherlands who were tested for SARS-CoV-2 between June and November 2020, when only symptomatic people were tested, and modelled ambient concentrations of PM10, PM2.5,  NO2 and O3 at geocoded residential addresses. In long-term exposure analysis, we selected individuals who did not change residential address in 2017-2019 (1.7 million tests) and considered the average concentrations of PM10, PM2.5 and NO2 in that period, and different sources of PM (industry, livestock, other agricultural activities, road traffic, other Dutch sources, foreign sources). In short-term exposure analysis, individuals not changing residential address in the two weeks before testing day (2.7 million tests) were included in the analyses, thus considering 1- and 2-week average concentrations of PM10, PM2.5,  NO2 and O3 before testing day as exposure. Mixed-effects logistic regression analysis with adjustment for several confounders, including municipality and testing week to account for spatiotemporal variation in viral circulation, was used. Overall, there was no statistically significant effect of long-term exposure to the studied pollutants on the odds of testing positive vs. negative for SARS-CoV-2. However, significant positive associations of long-term exposure to PM10 and PM2.5 from specifically foreign and livestock sources, and to PM10 from other agricultural sources, were observed. Short-term exposure to PM10 (adjusting for NO2) and PM2.5 were also positively associated with increased odds of testing positive for SARS-CoV-2. While these exposures seemed to increase COVID-19 risk relative to other respiratory diseases, the underlying biological mechanisms remain unclear. This study reinforces the need to continue to strive for better air quality to support public health.

Wastewater-based Epidemiology for COVID-19 Surveillance: A Survey (preprint)

The pandemic of COVID-19 has imposed tremendous pressure on public health systems and social economic ecosystems over the past years. To alleviate its social impact, it is important to proactively track the prevalence of COVID-19 within communities. The traditional way to estimate the disease prevalence is to estimate from reported clinical test data or surveys. However, the coverage of clinical tests is often limited and the tests can be labor-intensive, requires reliable and timely results, and consistent diagnostic and reporting criteria. Recent studies revealed that patients who are diagnosed with COVID-19 often undergo fecal shedding of SARS-CoV-2 virus into wastewater, which makes wastewater-based epidemiology (WBE) for COVID-19 surveillance a promising approach to complement traditional clinical testing. In this paper, we survey the existing literature regarding WBE for COVID-19 surveillance and summarize the current advances in the area. Specifically, we have covered the key aspects of wastewater sampling, sample testing, and presented a comprehensive and organized summary of wastewater data analytical methods. Finally, we provide the open challenges on current wastewater-based COVID-19 surveillance studies, aiming to encourage new ideas to advance the development of effective wastewater-based surveillance systems for general infectious diseases.

Polarised human alveolar epithelia enable identification of dichloroacetate as an effective drug against respiratory viruses (preprint)

Respiratory viral infections are a significant cause of morbidity and mortality worldwide. The COVID-19 pandemic has highlighted the lack of chemotherapeutic tools available for fighting emerging viruses and the need to focus on preclinical models that better recapitulate human disease. We performed a comparative analysis of inhibitors of the PI3K/AKT/mTOR pathway, which is involved in virus-induced metabolic reprogramming, since strategies aimed at identifying cellular targets could serve to combat diverse viruses and hamper the development of resistance. Tests were performed in two human cell lines, MRC5 lung fibroblasts and Huh7 hepatoma cells, and the results showed that the inhibitors had markedly different effects on energy metabolism and antiviral activity. Thus, dichloroacetate (DCA) has potent antiviral activity against HCoV-229E in MRC5 cells but not in Huh7 cells, suggesting that the screening model is more critical than previously assumed. DCA was then tested in polarized human alveolar epithelia in air-liquid interface, a 3D model used to study respiratory infections. DCA reduced the viral progeny of HCoV-229E, SARS-CoV-2 and respiratory syncytial virus by 2-3 orders of magnitude, and it was effective even when applied once infection had been established. Although DCA has previously been shown to be effective against other viruses, suggesting that it could be a broad-spectrum antiviral, our experiments reinforce the need to use physiologically appropriate disease models to screen antiviral compound. 

Validation of RT-qPCR primers and probes for new and old variants of SARS-CoV-2 in a world scale (preprint)

Introduction: The demand for molecular diagnosis of pathogens has surged dramatically since the onset of the COVID-19 pandemic. In this context, different diagnostic tests have been developed to identify SARS-CoV-2 in patient samples. The emergence of new variants of SARS-CoV-2 raises questions about whether the molecular tests available for diagnosis continue to be effective in detecting the virus in biological samples. Objective: This study analyzed the viability of molecular targets directed to N, E and RdRp genes available against the new variants of SARS-CoV-2. Methodology: For this, we used bioinformatics tools to analyze SARS-CoV-2 genomic data of different variants deposited in GSAID and NCBI virus genomic databases to assess the accuracy of molecular tests available for the diagnosis of COVID-19. We also developed software for analyzing mutation frequencies in different molecular targets from the mutation database. Results: Mutation frequency analysis revealed a high rate of mutations in the N, E and RdRp genes and targets, although the target regions were more conserved. Only three SNPs were recurrent in the sequences of the variants identified in different continents and all in different targets. On the other hand, the registered mutations are not consistent and do not appear frequently in isolates of the same variant in all regions of the world. Conclusion: Our data suggest that the molecular targets designed for the first SARS-CoV-2 variants remain valid for the identification of new virus variants despite the large number of identified haplotypes. However, false negative test failures can be identified by using more than one molecular target for the same sample. Genomic regions that are under evolutive selective pressure should be avoided in the use of the diagnostic, once the emergence of new variants may affect the efficiency of molecular testing on a global scale.

Multiperiod vaccination facility planning (preprint)

We propose a decision support tool, based on Mixed Integer Programming, to help with the planning of national vaccination campaigns, and test it on data and scenarios obtained from the publicly available information about the Irish COVID-19 vaccination program. We show that a large variety of constraints can be included in the tool, as well as combinations of different objective functions for the different stakeholders. The tests show that the multi-period/multi-vaccine problem can be effectively solved by the given model, while allowing to consider the impact of potential changes in the input data. We also present a number of specific visualizations that help the user understand the plan created by the application.

Creutzfeldt-Jakob Disease with Initial Typical Parkinsonism Precipitated by COVID-19? A Case Report (preprint)

Background Creutzfeldt-Jakob disease (CJD) is a rare and fatal neurodegenerative disease caused by the accumulation of PrPSc. While COVID-19-induced sporadic CJD (sCJD) with parkinsonism as the initial symptom is extremely uncommon, this report aims to raise awareness of sCJD cases that present with parkinsonism that are not associated with genetic mutations or pathological α-synuclein (α-Syn) accumulation. Case presentation This report presents the case of a 72-year-old man with probable sporadic Creutzfeldt-Jakob disease (sCJD) who initially showed symptoms of parkinsonism, which worsened rapidly after contracting COVID-19. Despite a history of responsive tremor and bradykinesia, his condition deteriorated following the viral infection, leading to rapid consciousness decline and diffuse myoclonus. Diagnostic tests, including brain MRI, cerebrospinal fluid analysis, and EEG, pointed towards prion disease. PrPSc, a marker for CJD, was detected in both the cerebrospinal fluid and skin samples using RT-QuIC, further confirming the diagnosis. Notably, skin analysis revealed PrPSc but no pathological α-synuclein deposits, ruling out typical Parkinson's disease.  Conclussion This case underscores the importance of considering sCJD in patients with parkinsonism, especially if they experience sudden neuropsychiatric symptoms, especially if they do not exhibit pathological α-Syn accumulation or have genetic mutations.

The relationship between maternal anxiety due to the COVID-19 pandemic and children's anxiety following school reopening in the post-pandemic era: an analytical cross-sectional study (preprint)

Background Although infection rates and mortality have decreased, COVID-19-related anxiety persists in families, especially among mothers, even in the post-pandemic period. Maternal mental health issues may jeopardize various aspects of children's development. This study aims to explore the correlation between maternal COVID-related anxiety and their children's anxiety following the reopening of primary schools in the post-pandemic era.Methods This analytical cross-sectional study involved the selection of 305 pairs of mothers and children. Data collection instruments comprised demographic questionnaires as well as assessments for COVID-related anxiety and manifest anxiety. Statistical analyses encompassed independent t-tests, one-way analysis of variance (ANOVA), and multivariate regression.Results Children's manifest anxiety was predicted by maternal anxiety related to COVID-19 (B = 0.907, P < 0.001). Moreover, significant associations were observed between the mean difference in mothers' COVID anxiety scores and their educational attainment and occupation, as well as their children's education and age, residential area, and their husbands' education and occupation (P < 0.001). Conversely, no significant differences were detected in maternal COVID anxiety scores concerning maternal age, spouse's age, and child's gender (P > 0.05).Conclusions Given the study's findings, it is recommended that nurses and psychologists provide educational interventions for mothers who need psychological support.