Development and validation of indirect ELISA for antibody detection against different protein antigens of porcine epidemic diarrhea virus in the colostrum and milk of sows.

The objectives of this study are to develop and optimize indirect ELISA based on three coating antigens of porcine epidemic diarrhea virus (PEDV), recombinant spike (S12), nucleocapsid (N), and whole viral (WV) proteins, for the detection of IgG and IgA antibodies in colostrum and milk and to evaluate the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay as a diagnostic method. Colostrum (n = 347) and milk (n = 272) samples from sows were employed in this assay. Indirect ELISA based on three coating antigens was assessed by receiver operating characteristic (ROC) curve analysis with a virus neutralization (VN) test as a reference method, and the cutoff value for calculating DSe and DSp was determined. S12-ELISA showed higher DSe and DSp of IgG and IgA detection compared to N- and WV-ELISA in both colostrum and milk samples. Moreover, S12-ELISA showed perfect agreement and a high correlation with the VN test, which was better than the N- and WV-ELISA for both IgG and IgA detection in colostrum and milk. In contrast, N-ELISA showed lower DSe and DSp compared to S12- and WV-ELISA, along with a correlation with VN and substantial agreement with the VN test. Nevertheless, our developed ELISAs have accuracy for repeatability in both inter- and intra-assay variation. Overall, this research demonstrates that S12-ELISA is more suitable than WV- and N-ELISA to detect IgG and IgA antibodies against PEDV from both colostrum and milk samples.

Effects of Amino Acid-Bound Zinc and Manganese Feed Additives on MHC Haplotype Chickens Challenged with Infectious Bronchitis Coronavirus.

Major histocompatibility complex (MHC) congenic chicken lines have been used as a model to study infectious bronchitis virus (IBV) immune responses in chickens. Zinc (Zn) and manganese (Mn) are trace minerals that act as enzyme cofactors in cellular reactions. In addition, Zn is an important modulator of immune responses, especially in the respiratory tract. Zinc and Zn + Mn amino acid complex supplements were tested to alleviate the effects of an IBV challenge using relatively resistant and susceptible MHC congenic chicken lines. Prior to the challenge with IBV, the amino acid-bound supplements induced better weight gain in the IBV-resistant chicken line (331/B2) compared to the birds fed with the sulfate-delivered supplements. No body weight differences were detected between IBV-challenged and unchallenged 331/B2 birds supplemented with Zn in amino acid complex. A reduction of respiratory signs was observed in 335/B19 birds fed with the diet supplemented with Zn in amino acid complexes at 4 dpi. Compared to the sulfate-bound trace minerals, 331/B2 chickens fed with the amino acid-bound supplements presented milder clinical sign trends at 6 dpi and less severe airsacculitis at 14 dpi. The total antibody response in serum in 331/B2 birds fed with the amino acid-bound Zn ration was the highest among all groups tested. Both amino acid-delivered trace mineral supplements induced a slightly higher antibody response than the sulfate-bound ration in both chicken lines. This experiment provides insights into the effect of Zn and Mn on the immunity of chickens with known different susceptibilities to IBV.

Mini-Review on the Roles of Vitamin C, Vitamin D, and Selenium in the Immune System against COVID-19.

Low levels of micronutrients have been associated with adverse clinical outcomes during viral infections. Therefore, to maximize the nutritional defense against infections, a daily allowance of vitamins and trace elements for malnourished patients at risk of or diagnosed with coronavirus disease 2019 (COVID-19) may be beneficial. Recent studies on COVID-19 patients have shown that vitamin D and selenium deficiencies are evident in patients with acute respiratory tract infections. Vitamin D improves the physical barrier against viruses and stimulates the production of antimicrobial peptides. It may prevent cytokine storms by decreasing the production of inflammatory cytokines. Selenium enhances the function of cytotoxic effector cells. Furthermore, selenium is important for maintaining T cell maturation and functions, as well as for T cell-dependent antibody production. Vitamin C is considered an antiviral agent as it increases immunity. Administration of vitamin C increased the survival rate of COVID-19 patients by attenuating excessive activation of the immune response. Vitamin C increases antiviral cytokines and free radical formation, decreasing viral yield. It also attenuates excessive inflammatory responses and hyperactivation of immune cells. In this mini-review, the roles of vitamin C, vitamin D, and selenium in the immune system are discussed in relation to COVID-19.

Vitamin D3 as Potential Treatment Adjuncts for COVID-19.

Severe acute respiratory syndrome coronavirus type (SARS-CoV2, also known as COVID-19), which is the latest pandemic infectious disease, constitutes a serious risk to human health. SARS-CoV2 infection causes immune activation and systemic hyperinflammation which can lead to respiratory distress syndrome (ARDS). ARDS victims are characterized by a significant increase in IL-6 and IL-1. Macrophage activation, associated with the "cytokine storm", promotes the dysregulation of the innate immunity. So far, without vaccines or specific therapy, all efforts to design drugs or clinical trials are worthwhile. Vitamin D and its receptor vitamin D receptor (VDR) exert a critical role in infections due to their remarkable impact on both innate and adaptive immune responses and on the suppression of the inflammatory process. The protective properties of vitamin D supplementation have been supported by numerous observational studies and by meta-analysis of clinical trials for prevention of viral acute respiratory infection. In this review, we compare the mechanisms of the host immune response to SARS-CoV2 infection and the immunomodulatory actions that vitamin D exerts in order to consider the preventive effect of vitamin D supplementation on SARS-CoV2 viral infection.

COVID-19: Is there a role for immunonutrition in obese patient?

On December 12, 2019 a new coronavirus (SARS-CoV-2) emerged in Wuhan, China, triggering a pandemic of severe acute respiratory syndrome in humans (COVID-19). Today, the scientific community is investing all the resources available to find any therapy and prevention strategies to defeat COVID-19. In this context, immunonutrition can play a pivotal role in improving immune responses against viral infections. Immunonutrition has been based on the concept that malnutrition impairs immune function. Therefore, immunonutrition involves feeding enriched with various pharmaconutrients (Omega 3 Fatty Acids, Vitamin C, Arginine, Glutamine, Selenium, Zinc, Vitamin, E and Vitamin D) to modulate inflammatory responses, acquired immune response and to improve patient outcomes. In literature, significant evidences indicate that obesity, a malnutrition state, negatively impacts on immune system functionality and on host defense, impairing protection from infections. Immunonutrients can promote patient recovery by inhibiting inflammatory responses and regulating immune function. Immune system dysfunction is considered to increase the risk of viral infections, such as SARS-CoV-2, and was observed in different pathological situations. Obese patients develop severe COVID-19 sequelae, due to the high concentrations of TNF-α, MCP-1 and IL-6 produced in the meantime by visceral and subcutaneous adipose tissue and by innate immunity. Moreover, leptin, released by adipose tissue, helps to increase inflammatory milieu with a dysregulation of the immune response. Additionally, gut microbiota plays a crucial role in the maturation, development and functions of both innate and adaptive immune system, as well as contributing to develop obese phenotype. The gut microbiota has been shown to affect lung health through a vital crosstalk between gut microbiota and lungs, called the "gut-lung axis". This axis communicates through a bi-directional pathway in which endotoxins, or microbial metabolites, may affect the lung through the blood and when inflammation occurs in the lung, this in turn can affect the gut microbiota. Therefore, the modulation of gut microbiota in obese COVID-19 patients can play a key role in immunonutrition therapeutic strategy. This umbrella review seeks to answer the question of whether a nutritional approach can be used to enhance the immune system's response to obesity in obese patients affected by COVID-19.

Safety and efficacy of herbal extracts to restore respiratory health and improve innate immunity in COVID-19 positive patients with mild to moderate severity: A structured summary of a study protocol for a randomised controlled trial.

OBJECTIVES: Primary Objective • To assess the efficacy of herbal extracts in boosting innate immunity of patients with COVID-19 infection. Secondary Objectives • To assess the efficacy of herbal extracts in restoring respiratory health • To assess the efficacy of Cap. IP in early recovery of patients and decline in viral load • To assess the safety of herbal extracts TRIAL DESIGN: This is a single centre, randomized, 2-arm, parallel group, double blind, 1:1 ratio, controlled, exploratory trial with a study period of 30 days from the day of enrolment. PARTICIPANTS: Patients attending the COVID treatment centre at Yashwantrao Chavan Memorial Hospital, Nehrunagar, Pimpri, Pune, India were screened for their participation in the study. Patients who were known COVID-19 positive (with positive RT-PCR), eligible and willing were enrolled in the study. INTERVENTION AND COMPARATOR: The intervention in the trial has a background in 'Ayurved'. Intervention Arm: Two capsules, Investigational Product (IP) - 1 - 400mg and Investigational Product - 2 - 450mg, containing herbal extracts (a blend of water and CO2 extracts) of Shunthi (Zingiber officinale (Ginger), Vidanga (Embelia ribes), Yashtimadhu (Glycyrrhiza glabra), Haritaki (Terminalia chebula), Guduchi (Tinospora cordifolia), Shatavari (Asparagus racemosus), Aamalaki (Emblica officinalis), Pippali (Piper longum) and calcined Zinc, Shankha bhasma. Placebo Arm: Edible starch ~ 450 mg. The look and feel of IP and of Placebo boxes were very similar. Patients are to take two capsules (one each of IP-1 and IP-2) twice a day for 15 days, and from the 16th day, one capsule of IP-2 twice a day up-to day 30. Capsules are to be administered orally with plain water. The IP is to be taken with all other concomitant medicines prescribed by the treating physician/doctor. The dose of each component in the IP is very safe to administer. The investigational products are registered products with the Indian Government and have been used for more than 6 months in various health conditions but not for COVID-19. MAIN OUTCOMES: Primary Outcome: Efficacy of the herbal extracts in COVID 19 positive patients (in declining viral load: time-point: 4 days and early recovery) Secondary Outcomes: Efficacy of the herbal extracts as an immune-modulator - TH1, TH2, Th17, IL6, NK Cells and CD markers; Immunoglobulin IGG (Serum); Immunoglobulin IGM (Serum) - at 30 days. Efficacy of the investigational product in reducing sequela of the disease Safety analysis (Liver Function Test and Kidney Function Test) including serious allergic reaction of: rash, itching/swelling, severe dizziness, trouble breathing. RANDOMISATION: An alphanumeric coded set of IP/Placebo containers will be used. Participants will be automatically randomized to two groups in the ratio 1:1. BLINDING (MASKING): Participants, caregivers and investigators were blinded. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): A total of more than 60 and up to 75 patients were to be enrolled in the study into the two groups, considering drop-outs. 72 were enrolled with 37 into the intervention group and 35 into the placebo group. TRIAL STATUS: Protocol number: CoviQuest-01 Protocol version number: 1.2 Protocol Date: 1st July 2020 The recruitment period is completed for the trial. Date of 1st patient enrolment was 11th Aug 2020 and the last patient was enrolled on 3rd of September 2020. This is to state that it was a late submission from authors for publication of the protocol to the BMC, after enrolment in the study was over. Last Participant's last follow-up is scheduled on 5th October 2020 TRIAL REGISTRATION: The trial was prospectively registered with the CTRI (Clinical Trial Registry of India). Registration number is CTRI/2020/07/026570 . Registered on 14 July 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Effective Immune Functions of Micronutrients against SARS-CoV-2.

The third coronavirus outbreak in the last two decades has caused significant damage to the world's economy and community health. The highly contagious COVID-19 infection has affected millions of people to date and has led to hundreds of thousands of deaths worldwide. Aside from the highly infectious nature of SARS-CoV-2, the lack of a treatment or vaccine has been the main reason for its spread. Thus, it has become necessary to find alternative methods for controlling SARS-CoV-2. For the present review, we conducted an online search for different available nutrition-based therapies for previously known coronavirus infections and RNA-based virus infections as well as general antiviral therapies. These treatments have promise for combating COVID-19, as various nutrients and minerals play direct and indirect roles in the control and prevention of this newly emerged viral infection. The patients' nutritional status with COVID-19 must be analyzed before administering any treatment, and nutritional supplements should be given to the affected individuals along with routine treatment. We suggest a potential interventional role of nutrients to strengthen the immune system against the emerging infection caused by COVID-19.

COVID-19 and 'immune boosting' on the internet: a content analysis of Google search results.

OBJECTIVE: The spread of misinformation has accompanied the coronavirus pandemic, including topics such as immune boosting to prevent COVID-19. This study explores how immune boosting is portrayed on the internet during the COVID-19 pandemic. DESIGN: Content analysis. METHODS: We compiled a dataset of 227 webpages from Google searches in Canada and the USA using the phrase 'boost immunity' AND 'coronavirus' on 1 April 2020. We coded webpages for typology and portrayal of immune boosting and supplements. We recorded mentions of microbiome, whether the webpage was selling or advertising an immune boosting product or service, and suggested strategies for boosting immunity. RESULTS: No significant differences were found between webpages that appeared in the searches in Canada and the USA. The most common types of webpages were from news (40.5%) and commercial (24.7%) websites. The concept of immune boosting was portrayed as beneficial for avoiding COVID-19 in 85.5% of webpages and supplements were portrayed as beneficial in 40% of the webpages, but commercial sites were more likely to have these portrayals. The top immune boosting strategies were vitamin C (34.8%), diet (34.4%), sleep (34.4%), exercise (30.8%) and zinc (26.9%). Less than 10% of the webpages provide any critique of the concept of immune boosting. CONCLUSIONS: Pairing evidence-based advice for maintaining one's health (eg, healthy diet, exercise, sleep) with the phrase immune boosting and strategies lacking in evidence may inadvertently help to legitimise the concept, making it a powerful marketing tool. Results demonstrate how the spread of misinformation is complex and often more subtle than blatant fraudulent claims.

The clinical effect of Nano micelles containing curcumin as a therapeutic supplement in patients with COVID-19 and the immune responses balance changes following treatment: A structured summary of a study protocol for a randomised controlled trial.

OBJECTIVES: To investigates the effectiveness of curcumin-containing Nanomicelles as a therapeutic supplement in the treatment of patients with COVID-19 and its effect on immune responses balance changes following treatment. TRIAL DESIGN: This study is conducted as a prospective, placebo-controlled with parallel group, single-center randomized clinical trial on COVID-19 patients. PARTICIPANTS: Patients are selected from the COVID-19 ward of Shahid Mohammadi Hospital in Bandar Abbas, Iran. INCLUSION CRITERIA: 1. Real time PCR-approved positive COVID-19 test. 2. Both gender 3. Age between 18 and 75 years 4. Signing a written consent 5. Lack of participation in other clinical trials Exclusion criteria: 1. Pregnancy or lactation 2. Allergy to turmeric or curcumin 3. Smoking 4. Patient connected to the ventilator 5. SaO2 less than 90% or PaO2 less than 8 kPa 6. Having comorbidities (such as severe renal failure, Glomerular filtration rate less than 30 ml/min, liver failure, Congestive heart failure, or Chronic obstructive pulmonary disease) 7. History of gallstones 8. History of gastritis or active gastrointestinal ulcer INTERVENTION AND COMPARATOR: In addition to the routine standard treatments for COVID-19, in the intervention group, 40mg nanomicelles containing curcumin (SinaCurcumin Capsule, Exir Nano Sina Company, Iran), four times per day (after breakfast, lunch, dinner and before bedtime) and in the placebo group as the control group, capsules with the same appearance and characteristics (Placebo capsules, Exir Nano Sina Company, Iran) are prescribed for two weeks. MAIN OUTCOMES: The effectiveness of Nano micelles containing curcumin treatment will be evaluated as daily clinical examinations of patients in both groups and, on days 0, 7 and 14, complete clinical symptoms and laboratory findings including peripheral blood and serum parameters such as inflammatory markers will be measured and recorded. Moreover, in order to evaluate the balance of immune responses changes following treatments, serum level of IFN-γ, IL-17, Il-4 and TGF-ß serum cytokines will be measured in both groups at time points of 0, 7 and 14 days post treatment. Gene expression of t-bet, GATA-3, FoxP3 and ROR- γT will also be measured at mentioned time points to assess the shift of T helper1, T helper2, T regulatory and T helper 17 immune responses following treatment. RANDOMISATION: Randomized trials will be performed on 40 COVID-19 patients which will be randomized using encoded sealed boxes with computer generated random digits with 1:1 allocation ratio. In order to randomization, placebo and SinaCurcumin Capsules will be numbered first by computer generated random digits. SinaCurcumin and placebo will then be stored and numbered in sealed packages based on generated random numbers. Finally, according to the order in which patients enter the study, packages are given to patients based on their number. BLINDING (MASKING): The present study will be blind for all patients, physicians and nurses, laboratory technicians and statisticians. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): A total of 40 patients will be included in the study, 20 of them will be randomly assigned to the intervention group and 20 to the placebo group. TRIAL STATUS: This is Version 1.0 of protocol dated 21 May 2020. The recruitment was started June 24, 2020 and is expected to be completed by October 31, 2020. TRIAL REGISTRATION: This present clinical trial has been registered in the Iranian Registry of Clinical Trials (IRCT) with the registration code of "IRCT20200611047735N1", https://www.irct.ir/trial/48843 . Dated: 19 June 2020. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Bromelain: A Review on its Potential as a Therapy for the Management of Covid-19.

Coronavirus Disease 2019 is a wide-spreading severe viral disease caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2) virus that needs to be urgently eradicated. SARS-COV-2 has infected millions of people worldwide and results in more than three hundred thousand deaths. Several repurposed drugs have failed to successfully eradicate the infection. Multiorgan failure caused by pronounced inflammation and systemic coagulation accounts for severe complications and death associated with diseases. Bromelain appears to be a potential candidate that may be used to inhibit or prevent the symptoms of the diseases. Its anti-inflammatory and anticoagulatory properties make it a potential agent that may slow the progression of the disease. In this review, we highlighted the beneficial effects of bromelain based on both experimental and clinical evidence that make bromelain a good candidate for the treatment of symptoms of CoVID-19 infection.

Beekeepers who tolerate bee stings are not protected against SARS-CoV-2 infections.

A survey on 5115 beekeepers and 121 patients treated with bee venom by an apitherapy clinic in the Hubei province, the epicenter of COVID-19 in China, reported that none of the beekeepers developed symptoms associated with COVID-19, the new and devastating pandemic. The hypothesis that immunity to bee venom could have a preventive effect was expressed and the authors of the Chinese survey suggested that the next step should be animal experiments on monkeys. We believed that before starting such studies, a second independent survey should verify the findings and define the hypothesis more clearly. Thus we asked all German beekeepers to complete an assessment form which would summarize their experiences with COVID-19. In contrast to the Chinese study we found that two beekeepers had died from a SARS-CoV-2 infection and forty-five were affected. The reaction to bee stings (none; mild swelling; severe swelling) correlated with the perceived severity of the SARS-CoV-2-infection-associated symptoms - exhaustion and sore throat. Beekeepers comorbidity correlated with problems with breathing at rest, fever, and diarrhea. Our results did not confirm the findings of the Chinese study. However, since the antiviral effects of bee venom have been found in several studies, we cannot exclude that there could be a direct preventive or alleviating effect when bee venom is administered during the infection.

Omega-3 fatty acids in the psychological and physiological resilience against COVID-19.

As the infected cases of COVID-19 reach more than 20 million with more than 778,000 deaths globally, an increase in psychiatric disorders including anxiety and depression has been reported. Scientists globally have been searching for novel therapies and vaccines to fight against COVID-19. Improving innate immunity has been suggested to block progression of COVID-19 at early stages, while omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been shown to have immunomodulation effects. Moreover, n-3 PUFAs have also been shown to improve mood disorders, thus, future research is warranted to test if n-3 PUFAs may have the potential to improve our immunity to counteract both physical and mental impact of COVID-19.

Impacts of the COVID-19 Pandemic on Food Security and Diet-Related Lifestyle Behaviors: An Analytical Study of Google Trends-Based Query Volumes.

The severe acute respiratory syndrome coronavirus (SARS-CoV)-2 disease (COVID)-19 is having profound effects on the global economy and food trade. Limited data are available on how this pandemic is affecting our dietary and lifestyle-related behaviors at the global level. Google Trends was used to obtain worldwide relative search volumes (RSVs) covering a timeframe from before the COVID-19 pandemic 1 June 2019 to 27 April 2020. Spearman's rank-order correlation coefficients were used to measure relationships between daily confirmed cases and aforementioned RSVs between 31 December 2019 and 15 April 2020. RSV curves showed increased interest in multiple keywords related to dietary and lifestyle behaviors during the COVID-19 lockdown period in March and April 2020. Spearman's correlation analysis showed that the strongest variables in each keyword category were (1) food security (food shortage: r = 0.749, food bank: r = 0.660, and free food: r = 0.555; all p < 0.001), (2) dietary behaviors (delivery: r = 0.780, restaurant: r = -0.731, take-away: r = 0.731, and food-delivery: r = 0.693; all p < 0.001), (3) outdoor-related behaviors (resort: r = -0.922, hotel: r = -0.913, cinema: r = -0.844, park: r = -0.827, fitness: r = -0.817, gym: r = -0.811; plant: r = 0.749, sunbathing: r = 0.668, and online: r = 0.670; all p < 0.001), and (4) immune-related nutrients/herbs/foods (vitamin C: r = 0.802, vitamin A: r = 0.780, zinc: r = 0.781, immune: r = 0.739, vitamin E: r = 0.707, garlic: r = 0.667, omega-3 fatty acid: r = -0.633, vitamin D: r = 0.549, and turmeric: r = 0.545; all p < 0.001). Restricted movement has affected peoples' dietary and lifestyle behaviors as people tend to search for immune-boosting nutrients/herbs and have replaced outdoor activities with sedentary indoor behaviors.

Possible application of high-dose vitamin C in the prevention and therapy of coronavirus infection.

Coronaviruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses increase oxidative stress in the body leading to cellular and tissue damage. To combat this, administration of high-dose vitamin C (ascorbic acid or ascorbate), in addition to standard conventional supportive treatments, has been shown to be a safe and effective therapy for severe cases of respiratory viral infection. Morbidity, mortality, infectiveness and spread of infectious diseases are dependent on the host-pathogen relationship. Given the lack of effective and safe antiviral drugs for coronaviruses, there should be more attention in supporting host immune defence, cytoprotection and immunoregulation. Implementation of high-dose vitamin C therapy could dramatically reduce the need for high doses of corticosteroids, antibacterials and antiviral drugs that may be immunosuppressive, adrenal depressive and toxic, complicating the disease course. In order to effectively fight the novel SARS-CoV-2 virus, medical professionals should explore readily available pharmaceutical and nutritional therapeutic agents with proven antioxidant, anti-inflammatory and immunosupportive properties. Supplemental vitamin C may also provide additional benefits for the prevention of viral infections, shorten the disease course and lessen complications of the disease.

Impact of Microbiota: A Paradigm for Evolving Herd Immunity against Viral Diseases.

Herd immunity is the most critical and essential prophylactic intervention that delivers protection against infectious diseases at both the individual and community level. This process of natural vaccination is immensely pertinent to the current context of a pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection around the globe. The conventional idea of herd immunity is based on efficient transmission of pathogens and developing natural immunity within a population. This is entirely encouraging while fighting against any disease in pandemic circumstances. A spatial community is occupied by people having variable resistance capacity against a pathogen. Protection efficacy against once very common diseases like smallpox, poliovirus or measles has been possible only because of either natural vaccination through contagious infections or expanded immunization programs among communities. This has led to achieving herd immunity in some cohorts. The microbiome plays an essential role in developing the body's immune cells for the emerging competent vaccination process, ensuring herd immunity. Frequency of interaction among microbiota, metabolic nutrients and individual immunity preserve the degree of vaccine effectiveness against several pathogens. Microbiome symbiosis regulates pathogen transmissibility and the success of vaccination among different age groups. Imbalance of nutrients perturbs microbiota and abrogates immunity. Thus, a particular population can become vulnerable to the infection. Intestinal dysbiosis leads to environmental enteropathy (EE). As a consequence, the generation of herd immunity can either be delayed or not start in a particular cohort. Moreover, disparities of the protective response of many vaccines in developing countries outside of developed countries are due to inconsistencies of healthy microbiota among the individuals. We suggested that pan-India poliovirus vaccination program, capable of inducing herd immunity among communities for the last 30 years, may also influence the inception of natural course of heterologous immunity against SARS-CoV-2 infection. Nonetheless, this anamnestic recall is somewhat counterintuitive, as antibody generation against original antigens of SARS-CoV-2 will be subdued due to original antigenic sin.

A point-of-care selenium nanoparticle-based test for the combined detection of anti-SARS-CoV-2 IgM and IgG in human serum and blood.

COVID-19 is a widespread and highly contagious disease in the human population. COVID-19 is caused by SARS-CoV-2 infection. There is still a great demand for point-of-care tests for detection, epidemic prevention and epidemiological investigation, both now and after the epidemic. We present a lateral flow immunoassay kit based on a selenium nanoparticle-modified SARS-CoV-2 nucleoprotein, which detects anti-SARS-CoV-2 IgM and anti-SARS-CoV-2 IgG in human serum, and the results can be read by the naked eye in 10 minutes. We expressed and purified the SARS-CoV-2 nucleoprotein in HEK293 cells, with a purity of 98.14% and a concentration of 5 mg mL-1. Selenium nanoparticles were synthesized by l-ascorbic acid reduction of seleninic acid at room temperature. After conjugation with the nucleoprotein, a lateral flow kit was successfully prepared. The IgM and IgG detection limits of the lateral flow kit reached 20 ng mL-1 and 5 ng mL-1, respectively, in human serum. A clinical study sample comprising 90 COVID-19-diagnosed patients and 263 non-infected controls was used to demonstrate a sensitivity and specificity of 93.33% and 97.34%, respectively, based on RT-PCR and clinical results. No cross-reactions with rheumatoid factor and positive serum for anti-nuclear antibodies, influenza A, and influenza B were observed. Moreover, the lateral flow kit remained stable after storage for 30 days at 37 °C. Our results demonstrate that the selenium nanoparticle lateral flow kit can conveniently, rapidly, and sensitively detect anti-SARS-CoV-2 IgM and IgG in human serum and blood; it can also be suitable for the epidemiological investigation of COVID-19.

The Role of Micronutrients in Support of the Immune Response against Viral Infections.

Viral infections are a leading cause of morbidity and mortality worldwide, and the importance of public health practices including handwashing and vaccinations in reducing their spread is well established. Furthermore, it is well known that proper nutrition can help support optimal immune function, reducing the impact of infections. Several vitamins and trace elements play an important role in supporting the cells of the immune system, thus increasing the resistance to infections. Other nutrients, such as omega-3 fatty acids, help sustain optimal function of the immune system. The main aim of this manuscript is to discuss of the potential role of micronutrients supplementation in supporting immunity, particularly against respiratory virus infections. Literature analysis showed that in vitro and observational studies, and clinical trials, highlight the important role of vitamins A, C, and D, omega-3 fatty acids, and zinc in modulating the immune response. Supplementation with vitamins, omega 3 fatty acids and zinc appears to be a safe and low-cost way to support optimal function of the immune system, with the potential to reduce the risk and consequences of infection, including viral respiratory infections. Supplementation should be in addition to a healthy diet and fall within recommended upper safety limits set by scientific expert bodies. Therefore, implementing an optimal nutrition, with micronutrients and omega-3 fatty acids supplementation, might be a cost-effective, underestimated strategy to help reduce the burden of infectious diseases worldwide, including coronavirus disease 2019 (COVID-19).

A Single Large Dose of Vitamin D Could be Used as a Means of Coronavirus Disease 2019 Prevention and Treatment.

There is no specific and effective medication for coronavirus disease 2019 (COVID-19), and avaccine is not available in recent months. Here, we hypothesize that a single large dose of vitamin D (Vit D) could be an option for trial in COVID-19. Vit D deficiency or insufficiency is very common in the general population as well as in patients with COVID-19. It has been shown that low Vit D level is associated with viral infection, and Vit D supplementation is beneficial for people infected with viruses, such as HIV and hepatitis C virus. Although COVID-19 is a respiratory disease, the morbidity and mortality of this disease are driven by coagulopathy. Clinical studies have shown that Vit D can exert anticoagulant effects. Vit D, a lipid-soluble vitamin, can be administered as a draught. Vit D supplementation is safe and has rare toxic events. In addition, the cost of Vit D is fairly low. Based on these observations, we speculate that a single dose of 300,000 IU Vit D may have a role in the prevention and treatment of COVID-19.