Routine childhood immunization may protect against COVID-19

Multi-modal fusion of deep transfer learning based COVID-19 diagnosis and classification using chest x-ray images

COVID-19 pandemic has a significant impact on the global health and daily lives of people living over the globe. Several initial tests are based on the detecting of the genetic material of the coronavirus, and they have a minimum detection rate with a time-consuming process. To overcome this issue, radiological images are recommended where chest X-rays (CXRs) are employed in the diagnostic process. This article introduces a new Multi-modal fusion of deep transfer learning (MMF-DTL) technique to classify COVID-19. The proposed MMF-DTL model involves three main processes, namely pre-processing, feature extraction, and classification. The MMF-DTL model uses three DL models namely VGG16, Inception v3, and ResNet 50 for feature extraction. Since a single modality would not be adequate to attain an effective detection rate, the integration of three approaches by the use of decision-based multimodal fusion increases the detection rate. So, a fusion of three DL models takes place to further improve the detection rate. Finally, a softmax classifier is employed for test images to a set of six different. A wide range of experimental result analyses is carried out on the Chest-X-Ray dataset. The proposed fusion model is found to be an effective tool for COVID-19 diagnosis using radiological images with the average sens _y of 92.96%, spec _y of 98.54%, prec _n of 93.60%, accu _y of 98.80%, F _score of 93.26% and kappa of 91.86%.

Current status of COVID-19 vaccination: safety and liability concern for children, pregnant and lactating women

INTRODUCTION

: Since its inception, Coronavirus disease-19 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has claimed a significant number of lives around the world.

AREA COVERED

: COVID-19 vaccine development involves several vaccine platforms, including traditional live-attenuated or killed viral particles, viral vectors or DNA, and mRNA-based vaccines. The efficacy and effectiveness (EV) of these vaccines must be assessed in order to determine the extent to which they can protect us against infection. Despite the fact that some affluent countries attempted to vaccinate the majority of their inhabitants, children and pregnant women were first excluded.

EXPERT OPINION

: While the severity of COVID-19 is less severe in children, the COVID-19-related complications are more severe.SARS-CoV-2 infection is also dangerous for pregnant women. The key to limiting disease spread is early discovery, isolation, and the development of safe and efficient vaccinations. As a result, the purpose of this study is to highlight the current development of various COVID-19 vaccine platforms for different groups of people at higher risk of COVID-19, with a special focus on children, pregnant and lactating women, as well as structural and pathogenicity elements of SARS CoV-2.

A cognitive framework based on deep neural network for classification of coronavirus disease

Since December 2019, the pandemic of coronavirus (CorV) is spreading all over the world. CorV is a viral disease that results in ill effects on humans and is recognized as public health concern globally. The objective of the paper is to diagnose and prevent the spread of CorV. Spatio-temporal based fine-tuned deep learning model is used for detecting Corv disease so that the prevention measures could be taken on time. Deep learning is an emerging technique that has an extensive approach to prediction. The proposed system presents a hybrid model using chest X-ray images to early identify the CorV suspected people so that necessary action can be taken timely. The proposed work consists of various deep learning neural network algorithms for the identification of CorV patients. A decision model with enhanced accuracy has been presented for early identification of the suspected CorV patients and time-sensitive decision-making. A SQueezeNet model is used for the classification of the CorV patient. An experiment has been conducted for validation purposes to register an average accuracy of 97.8%. Moreover, the outcomes of statistical parameters are compared with numerous state-of-the-art decision-making models in the current domain for performance assessment.

Pediatric COVID-19 and Gastrointestinal Symptoms in Africa

One year into the coronavirus disease 2019 (COVID-19) pandemic, the African continent still seems to be spared from the devastating effects the disease had in other continents. Africa's COVID-19 seems to be of a milder nature both in adults and children. However, lack of data from Africa is significant, and more studies are needed to validate the disease status, clinical manifestations, and future implications for Africa. In this study, we report pediatric COVID-19 features in Africa represented by 8 countries.

Vaccination With Routine Childhood Vaccines and Severity of COVID-19 Among Children in Delhi

Objective

Methods

Results

Conclusions

Electronic Supplementary Material

Automatic Detection of Covid-19 with Bidirectional LSTM Network Using Deep Features Extracted from Chest X-ray Images

Coronavirus disease, which comes up in China at the end of 2019 and showed different symptoms in people infected, affected millions of people. Computer-aided expert systems are needed due to the inadequacy of the reverse transcription-polymerase chain reaction kit, which is widely used in the diagnosis of this disease. Undoubtedly, expert systems that provide effective solutions to many problems will be very useful in the detection of Covid-19 disease, especially when unskilled personnel and financial deficiencies in underdeveloped countries are taken into consideration. In the literature, there are numerous machine learning approaches built with different classifiers in the detection of this disease. This paper proposes an approach based on deep learning which detects Covid-19 and no-finding cases using chest X-ray images. Here, the classification performance of the Bi-LSTM network on the deep features was compared with the Deep Neural Network within the frame of the fivefold cross-validation technique. Accuracy, sensitivity, specificity and precision metrics were used to evaluate the classification performance of the trained models. Bi-LSTM network presented better performance compare to DNN with 97.6% value of high accuracy despite the few numbers of Covid-19 images in the dataset. In addition, it is understood that concatenated deep features more meaningful than deep features obtained with pre-trained networks by one by, as well. Consequently, it is thought that the proposed study based on the Bi-LSTM network and concatenated deep features will be noteworthy in the design of highly sensitive automated Covid-19 monitoring systems.

Measles, mumps, and rubella (MMR) vaccine and COVID-19: a systematic review

This study was performed to investigate published literature about the association between measles, mumps, and rubella (MMR) vaccine and COVID-19. This is a systematic review in which the databases of Chocrane, Pubmed, Scopus, Web of Science as well as reliable journals including Lancet, New England Journal of Medicine, Jama and also Centers for Disease Control and Prevention (CDC) publications were searched.Out of 169 documents discovered during the literature review, 56 ones were somehow related to the association between MMR vaccine and COVID-19, of which 11 ones mentioned the association between these two, and 8 of them contained a hypothesis about this relationship. A quasi-trial study reported the positive effect of the MMR vaccine on reducing the severity of COVID-19 symptoms among those who received it. Also, a cross-sectional study showed an association between the level of Immunoglobulin G (IgG) mumps and COVID-19. Moreover, a genomic data analysis study also reported the effect of Rubella Immunoglobulin G (IgG) level on COVID-19. It seems that due to the similarity of respiratory diseases including measles, rubella, and mumps to COVID-19, MMR vaccine should be investigated more deeply to see if it is effective in order to deal with this novel disease.

Bacille Calmette-Guérin (BCG) vaccine and potential cross-protection against SARS-CoV-2 infection - Assumptions, knowns, unknowns and need for developing an accurate scientific evidence base

After a century of controversies on its usefulness in protection against TB, underlying mechanisms of action, and benefits in various groups and geographical areas, the BCG vaccine is yet again a focus of global attention- this time due to the global COVID-19 pandemic caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Recent studies have shown that human CD4+ and CD8+ T-cells primed with a BCG-derived peptide developed high reactivity to its corresponding SARS-CoV-2-derived peptide. Furthermore, BCG vaccine has been shown to substantially increase interferon-gamma (IFN-g) production and its effects on CD4+ T-cells and these non-specific immune responses through adjuvant effect could be harnessed as cross protection against severe forms of COVID-19.The completion of ongoing BGG trials is important as they may shed light on the mechanisms underlying BCG-mediated immunity and could lead to improved efficacy, increased tolerance of treatment, and identification of other ways of combining BCG with other immunotherapies.

Is there a link between pre-existing antibodies acquired due to childhood vaccinations or past infections and COVID-19? A case control study

Background

There is growing evidence indicating that children are less affected from COVID-19. Some authors speculate that childhood vaccinations may provide some cross-protection against COVID-19. In this study, our aim was to compare the circulating antibody titers for multiple childhood vaccine antigens, as an indicator of the state of immune memory between patients with COVID-19 and healthy controls, with a specific aim to identify the association between disease severity and antibody titrations which may indicate a protective function related to vaccine or disease induced memory.

Methods

This study is a case-control study including 53 patients with COVID-19 and 40 healthy volunteers. COVID-19 severity was divided into three groups: asymptomatic, mild and severe. We measured the same set of antibody titers for vaccine antigens, and a set of biochemical and infection markers, in both the case and control groups.

Results

Rubella (p = 0.003), pneumococcus (p = 0.002), and Bordetella pertussis (p < 0.0001) titers were found to be significantly lower in the case group than the control group. There was a significant decline in pneumococcus titers with severity of disease (p = 0.021) and a significant association with disease severity for Bordetella pertussis titers (p = 0.014) among COVID patients. Levels of AST, procalcitonin, ferritin and D-dimer significantly increased with the disease severity.

Discussion

Our study supports the hypothesis that pre-existing immune memory, as monitored using circulating antibodies, acquired from childhood vaccinations, or past infections confer some protection against COVID-19. Randomized controlled studies are needed to support a definitive conclusion.

Current limitations to identify COVID-19 using artificial intelligence with chest X-ray imaging

The scientific community has joined forces to mitigate the scope of the current COVID-19 pandemic. The early identification of the disease, as well as the evaluation of its evolution is a primary task for the timely application of medical protocols. The use of medical images of the chest provides valuable information to specialists. Specifically, chest X-ray images have been the focus of many investigations that apply artificial intelligence techniques for the automatic classification of this disease. The results achieved to date on the subject are promising. However, some results of these investigations contain errors that must be corrected to obtain appropriate models for clinical use. This research discusses some of the problems found in the current scientific literature on the application of artificial intelligence techniques in the automatic classification of COVID-19. It is evident that in most of the reviewed works an incorrect evaluation protocol is applied, which leads to overestimating the results.

[Effects of the COVID-19 Pandemic on childhood immunization in Morocco: electronic survey of 103 pediatricians]

Introduction

no one can deny that vaccination against several serious diseases in the world, and particularly in Morocco, has given very satisfactory protective results. The extension of the COVID-19 pandemic in our country has led to a significant decline in childhood immunization, which could have severe repercussions increasing the risk of future outbreaks. Hence, the measures of the Ministry of Health to correct the situation. The purpose of this study was to highlight the extent of vaccine release during COVID-19 pandemic and to make recommendations to restore vaccination programmes.

Methods

we conducted a cross-sectional study of the effect of containment measures during this pandemic on the monitoring of children´s vaccinations. We conducted a national survey of pediatricians using an electronic questionnaire administered via Google Forms. We collected, analyzed and interpreted the results.

Results

one hundred and three Moroccan pediatricians answered the questionnaire. More than 2-thirds (78.6%) of pediatricians practiced in the private sector and delivered vaccines in the immunization schedule. The majority of pediatricians (95%) were asked about parental vaccine concerns. We noted that 82.5% of parents were reluctant to go to the local health department and 5.8% refused to take vaccination during COVID-19 pandemic. About 22% of pediatricians completely stopped immunization services and 72.8% delayed immunizations from 3 to 4 weeks. Vaccination stoppage involved older children in two thirds of cases.

Conclusion

it is essential to maintain public confidence in vaccination. Ongoing and timely assessment of vaccine coverage as well as clear recommendations and broad public awareness are essential to respond to vaccine changes during the COVID-19 pandemic.

COVID-19 in Egyptian Children: A Multicenter Study

Objective The novel coronavirus disease 2019 (COVID-19) has made its worldwide spread since its outbreak in December 2019. Limited information is available about the epidemiology and clinical characteristics of COVID-19, especially in Africa and Egypt.

Methods We aimed to study the clinical and epidemiological characteristics of COVID-19 in Egyptian children. This is an observational retrospective cohort study performed at two specialized COVID-19 isolation hospitals in Egypt. All admitted COVID-19 pediatric patients between March 20, 2020, and May 1, 2020, were included in the study.

Discussion This study included 40 COVID-19 confirmed cases (mean age, 9.4 years), 67.5% were male, 85% were asymptomatic, and 15% had mild symptoms. There were no confirmed severe or critically ill cases among the patients.

Conclusion COVID-19 runs in a benign course in Egyptian children with no mortality and no significant morbidity.

VACCINATION WITH MMR MAY REDUCE DISEASE SEVERITY IN COVID-19 PATIENTS

We hypothesise that MMR vaccination is possibly a safe, cheap, effective and readily available method to reduce the severity of COVID-19 disease course in health care workers, elderly patients and other people at risk. The evidence is based on relevant literature.  Suggestions for further studies are given.

BCG vaccine: a hope to control COVID-19 pandemic amid crisis

COVID-19 caused by the virus SARS-CoV-2 has gripped essentially all countries in the world, and has infected millions and killed hundreds of thousands of people. Several innovative approaches are in development to restrain the spread of SARS-CoV-2. In particular, BCG, a vaccine against tuberculosis (TB), is being considered as an alternative therapeutic modality. BCG vaccine is known to induce both humoral and adaptive immunities, thereby activating both nonspecific and cross-reactive immune responses in the host, which combined could effectively resist other pathogens including SARS-CoV-2. Notably, some studies have revealed that SARS-CoV-2 infectivity, case positivity, and mortality rate have been higher in countries that have not adopted BCG vaccination than in countries that have done so. This review presents an overview of the concepts underlying BCG vaccination and its nonspecific immuological effects and protection, resulting in 'trained immunity' and potential utility for resisting COVID-19.

COVID-19 in children: Could pertussis vaccine play the protective role?

While COVID-19 continues to spread across the globe, diligent efforts are made to understand its attributes and dynamics to help develop treatment and prevention measures. The paradox pertaining to children being the least affected by severe illness poses exciting opportunities to investigate potential protective factors. In this paper, we propose that childhood vaccination against pertussis (whooping cough) might play a non-specific protective role against COVID-19 through heterologous adaptive responses in this young population. Pertussis is a vaccine-preventable infectious disease of the respiratory tract and it shares many similarities with COVID-19 including transmission and clinical features. Although pertussis is caused by a bacterium (Bordetella pertussis) while COVID-19 is a viral infection (SARS-CoV-2), previous data showed that cross-reactivity and heterologous adaptive responses can be seen with unrelated agents of highly divergent groups, such as between bacteria and viruses. While we build the arguments of this hypothesis on theoretical and previous empirical evidence, we also outline suggested lines of research from different fields to test its credibility. Besides, we highlight some concerns that may arise when attempting to consider such an approach as a potential public health preventive intervention against COVID-19.

Pneumonia in medical professionals during COVID-19 outbreak in cardiovascular hospital

Objectives

The pandemic of coronavirus associated disease (COVID-19) placed the health care workers at high risk. We investigated clinical and treatment characteristics of infected medical professionals in a cardiovascular hospital.

Methods

The study was retrospective, conducted in tertiary cardiovascular hospital and included employees with confirmed coronavirus infection. They filled out a questionnaire about health status, symptoms, admission to hospital and treatment. The vaccination status against tuberculosis, hepatitis B and seasonal influenza was assessed. Pneumonia was defined as CT finding of ground glass opacifications (GGO) with consolidations typical for COVID-19.

Results

The study included 107 confirmed cases of COVID - 19 out of 726 employees (15%). Most of the infected were from cardiac surgery department (74/107, 69%). Substantial number of employees did not have any symptoms [31 (28.9%)] and 38 patients (35.5%) were admitted to hospital. The average hospital length of stay was 8.1 ± 5.6 days. Seventy-five of 107 (70.1%) received seasonal influenza vaccine. Pneumonia with CT features of GGO and consolidation occurred in 25/107 (23.4%) patients of which 14/107 (13.1%) had bilateral involvement. In multivariate logistic regression analysis including recognized characteristics associated with worse outcomes in COVID-19 (obesity, diabetes mellitus, coronary artery disease, cerebrovascular disease, current smoking, heart failure, influenza immunization), only influenza immunization remained an independent predictor of occurrence of bilateral pneumonia (OR 0.207; 95%CI[0.050 – 0.847]; p = 0.029).

Conclusions

The association of influenza immunization and less aggressive form of pneumonia might provide a finding that supports the institution of preventive measures that can be beneficial in reduction of global coronavirus burden.

Childhood Immunization and COVID-19: An Early Narrative Review

The COVID-19 pandemic has evolved into arguably the largest global public health crisis in recent history—especially in the absence of a safe and effective vaccine or an effective anti-viral treatment. As reported, the virus seems to less commonly infect children and causing less severe symptoms among infected children. This narrative review provides an inclusive view of scientific hypotheses, logical derivation, and early analyses that substantiate or refute such conjectures. At the completion of a relatively less restrictive search of this evolving topic, 13 articles—all published in 2020, were included in this early narrative review. Directional themes arising from the identified literature imply the potential relationship between childhood vaccination and COVID-19—either based on the potential genomic and immunological protective effects of heterologous immunity, or based on observational associations of cross-immunity among vaccines and other prior endemic diseases. Our review suggests that immune response to the SARS-CoV-2 virus in children is different than in adults, resulting in differences in the levels of severity of symptoms and outcomes of the disease in different age groups. Further clinical investigations are warranted of at least three childhood vaccines: BCG, MMR, and HEP-A for their potential protective role against the SARS-CoV-2 virus.

Coronavirus-2019 Disease (COVID-19) in Children

COVID-19 disease affects all ages, but severe cases of the disease and mortality are very rarely seen among children. In most cases, they acquire the virus from their parents or from an another infected person. The exact reasons why the disease has a milder course in children is unknown but high numbers of Angiotensin Converting Enzyme-2 (ACE2) receptors, underdeveloped immune responses, cross-reaction with other viruses, protective effect of fetal hemoglobin and fewer outdoor activities as well as journeys, and nonexposure to air pollution, and smoking. Although many cases are asymptomatic, they can still shed the virus. Materno-fetal vertical transmission has not been shown so far. In symptomatic cases, clinical findings include fever and respiratory symptoms, followed by diarrhea and vomiting. There are signs indicating a possible association between Kawasaki disease and COVID-19. Clinical findings and diagnostic procedures in newborns, and older children are similar. Supportive therapy is essential and antiviral agents are not required in most cases. During cytokine storm, anti-inflammatory treatments may be tried. There is no evidence for transmission through breastmilk; therefore infected mothers should breastfeed their infants by taking all precautions. Routine immunizations of children should not be deferred during COVID-19 outbreak period. Psychological support for children who need to stay at home and for healthcare personnel should be provided.

Harnessing Memory NK Cell to Protect Against COVID-19

The worldwide struggle against the coronavirus disease 2019 (COVID-19) as a public health crisis continues to sweep across the globe. Up to now, effective antiviral treatment against COVID-19 is not available. Therefore, throughout virus infections, a thorough clarification of the virus-host immune system interactions will be most probably helpful to encounter these challenges. Emerging evidence suggests that just like SARS and MERS, COVID-19 primarily suppresses the innate immune system, enabling its stable propagation during the early stage of infection. Consequently, proinflammatory cytokines and chemokines have been increasing during infection progression associated with severe lung pathology. It is imperative to consider hyper inflammation in vaccine designing, as vaccine-induced immune responses must have a protective role against infection without leading to immunopathology. Among the front-line responders to viral infections, Natural Killer (NK) cells have immense therapeutic potential, forming a bridge between innate and adaptive responses. A subset of NK cells exhibits putatively increased effector functions against viruses following pathogen-specific and immunization. Memory NK cells have higher cytotoxicity and effector activity, compared with the conventional NK cells. As a pioneering strategy, prompt accumulation and long-term maintenance of these memory NK cells could be an efficacious viral treatment. According to the high prevalence of human cytomegalovirus (HCMV) infection in the world, it remains to be determined whether HCMV adaptive NK cells could play a protective role against this new emerging virus. In addition, the new adaptive-like KIR+NKG2C+ NK cell subset (the adaptive-like lung tissue residue [tr]NK cell) in the context of the respiratory infection at this site could specifically exhibit the expansion upon COVID-19. Another aspect of NK cells we should note, utilizing modified NK cells such as allogeneic off-the-shelf CAR-NK cells as a state-of-the-art strategy for the treatment of COVID-19. In this line, we speculate introducing NKG2C into chimeric antigen receptors in NK cells might be a potential approach in future viral immunotherapy for emerging viruses. In this contribution, we will briefly discuss the current status and future perspective of NK cells, which provide to successfully exploit NK cell-mediated antiviral activity that may offer important new tools in COVID-19 treatment.

Potential repurposed SARS-CoV-2 (COVID-19) infection drugs

The global outbreak of COVID-19 viral infection is associated with the absence of specific drug(s) for fighting this viral infection. About 10 million people are already infected, about 500 000 deaths all over the world to date. Great efforts have been made to find solutions for this viral infection, either vaccines, monoclonal antibodies, or small molecule drugs; this can stop the spread of infection to avoid the expected human, economic and social catastrophe associated with this infection. In the literature and during clinical trials in hospitals, several FDA approved drugs for different diseases have the potential to treat or reduce the severity of COVID-19. Repurposing of these drugs as potential agents to treat COVID-19 reduces the time and cost to find effective COVID-19 agents. This review article summarizes the present situation of transmission, pathogenesis and statistics of COVID-19 in the world. Moreover, it includes chemistry, mechanism of action at the molecular level of the possible drug molecules which are liable for redirection as potential COVID-19 therapeutic agents. This includes polymerase inhibitors, protease inhibitors, malaria drugs, lipid lowering statins, rheumatoid arthritis drugs and some miscellaneous agents. We offer research data and knowledge about the chemistry and biology of potential COVID-19 drugs for the research community in this field.

Significantly Improved COVID-19 Outcomes in Countries with Higher BCG Vaccination Coverage: A Multivariable Analysis

The COVID-19 pandemic that started in China has spread within 3 months to the entire globe. We tested the hypothesis that the vaccination against tuberculosis by Bacille Calmette–Guérin vaccine (BCG) correlates with a better outcome for COVID-19 patients. Our analysis covers 55 countries complying with predetermined thresholds on the population size and number of deaths per million (DPM). We found a strong negative correlation between the years of BCG administration and the DPM along with the progress of the pandemic, corroborated by permutation tests. The results from multivariable regression tests with 23 economic, demographic, health-related, and pandemic restriction-related quantitative properties, substantiate the dominant contribution of BCG years to the COVID-19 outcomes. The analysis of countries according to an age-group partition reveals that the strongest correlation is attributed to the coverage in BCG vaccination of the young population (0–24 years). Furthermore, a strong correlation and statistical significance are associated with the degree of BCG coverage for the most recent 15 years, but no association was observed in these years for other broadly used vaccination protocols for measles and rubella. We propose that BCG immunization coverage, especially among the most recently vaccinated population, contribute to attenuation of the spread and severity of the COVID-19 pandemic.

COVIDiagnosis-Net: Deep Bayes-SqueezeNet based diagnosis of the coronavirus disease 2019 (COVID-19) from X-ray images

The Coronavirus Disease 2019 (COVID-19) outbreak has a tremendous impact on global health and the daily life of people still living in more than two hundred countries. The crucial action to gain the force in the fight of COVID-19 is to have powerful monitoring of the site forming infected patients. Most of the initial tests rely on detecting the genetic material of the coronavirus, and they have a poor detection rate with the time-consuming operation. In the ongoing process, radiological imaging is also preferred where chest X-rays are highlighted in the diagnosis. Early studies express the patients with an abnormality in chest X-rays pointing to the presence of the COVID-19. On this motivation, there are several studies cover the deep learning-based solutions to detect the COVID-19 using chest X-rays. A part of the existing studies use non-public datasets, others perform on complicated Artificial Intelligent (AI) structures. In our study, we demonstrate an AI-based structure to outperform the existing studies. The SqueezeNet that comes forward with its light network design is tuned for the COVID-19 diagnosis with Bayesian optimization additive. Fine-tuned hyperparameters and augmented dataset make the proposed network perform much better than existing network designs and to obtain a higher COVID-19 diagnosis accuracy.

COVID-19 and dermatology: a comprehensive guide for dermatologists

Linked articles: COVID‐19 SPECIAL FORUM. J Eur Acad Dermatol Venereol 2020; 34: e291–e310.

Perspectives of Immune Therapy in Coronavirus Disease 2019

The global fight against coronavirus disease 2019 (COVID-19) is largely based on strategies to boost immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and prevent its severe course and complications. The human defence may include antibodies which interact with SARS-CoV-2 and neutralize its aggressive actions on multiple organ systems. Protective cross-reactivity of antibodies against measles and other known viral infections has been postulated, primarily as a result of the initial observations of asymptomatic and mild COVID-19 in children. Uncontrolled case series have demonstrated virus-neutralizing effect of convalescent plasma, supporting its efficiency at early stages of contracting SARS-CoV-2. Given the variability of the virus structure, the utility of convalescent plasma is limited to the geographic area of its preparation, and for a short period of time. Intravenous immunoglobulin may also be protective in view of its nonspecific antiviral and immunomodulatory effects. Finally, human monoclonal antibodies may interact with some SARS-CoV-2 proteins, inhibiting the virus-receptor interaction and prevent tissue injury. The improved understanding of the host antiviral responses may help develop safe and effective immunotherapeutic strategies against COVID-19 in the foreseeable future.