Association between ABO blood types and coronavirus disease 2019 (COVID-19), genetic associations, and underlying molecular mechanisms: a literature review of 23 studies

ABO blood group-related mechanism of infection of SARS-CoV-2: an overview of systematic reviews

Among the host genetic factors playing a role in the susceptibility to infectious diseases, the ABO blood group system is of utmost importance. Following the first reports in early 2020, the association between ABO blood groups and SARS-CoV-2 infection or COVID-19 severity has been thoroughly investigated. The aim of this narrative review is to provide an overview of systematic reviews regarding the link between ABO blood groups and such risks. The possible molecular mechanisms underlying these associations will also be discussed. ABO blood group has a robust association with susceptibility to infection but not with disease severity, and studies on long COVID anre still missing.Prov.

The Relationship of ABO and Rh Blood Group Types With Severe COVID-19 Disease Mortality in ICU Patients: Insights From a Single-Center Experience in Southern Saudi Arabia

Introduction The global COVID-19 pandemic has triggered an unprecedented public health crisis, emphasizing the need to understand factors influencing disease outcomes. This study explores the role of genetic variations in blood group antigens, particularly ABO and RhD, in shaping mortality rates among critically ill COVID-19 patients in the southern region of Saudi Arabia. Methods Utilizing a retrospective, noninterventional approach, we analyzed medical records of 594 COVID-19 patients admitted to the intensive care unit (ICU) at Aseer Central Hospital from August 2020 to April 2021. The cohort, with a mean age of 60.5 years, consisted of a predominantly male population. Results The study encompassed a diverse age range of 18 to 103 years, with a mean age of 60.5 ± 17.3 years. Of the 594 patients, 398 (67%) were male, and only 5 (0.8%) had a history of smoking. Blood group distribution revealed 275 (48.4%) with O-, 189 (33.3%) with A+, and 51 (9%) with AB- types. Predominant chronic conditions included diabetes mellitus (35.5%). Tragically, 320 patients (54.6%) experienced mortality, with a 100% mortality rate for the B+ blood group and 92.9% for O- blood group. Conclusion This analysis establishes significant statistical links, underscoring the pivotal role of blood type, particularly the Rh factor, in influencing mortality risk among critically ill COVID-19 patients. These findings contribute valuable insights into risk stratification and personalized care for severe cases, emphasizing the importance of genetic considerations in understanding disease outcomes.

Rhesus factor is a stronger predictor for the risk of Sars-CoV-2 and mortality than ABO blood types

Objectives

In this study, we aimed to evaluate the relationship between ABO blood groups and Rhesus factor (Rf) and severe acute respiratory syndrome coronavirus-2 (Sars-CoV-2), as well as the risk of infection susceptibility and death according to pre-existing comorbidities.

Methods

This retrospective study included patients medical record between March 2020 and March 2021. A total 470 patients were included in the study. The subjects were categorized according to diagnose of Sars-CoV-2. Also, we evaluated the subject according to severity of Sars-CoV-2 infection. The logistic and multivariate regression analysis were performed to predict possible effect of ABO and Rf types as well as comorbidities on indicators of Sars-CoV-2 severity including Intensive care unit (ICU) hospitalization, intubation, and mortality.

Results

The distribution of ABO blood type and Rf were not statistically different cases with and without Sars-CoV-2. Blood type B and A were the most groups in intubation and mortality among patients with Sars-CoV-2. However, ABO blood types had no significant effect on risk of Sars-CoV-2 and mortality while, Rf had a significantly effect on it. Additionally, Rf had a statistically significant effect on all severity indicators of Sars-CoV-2 but ABO had not.

Conclusions

While Rf was significantly associated with risk of Sars-CoV-2 and had a strong effect on ICU admission, intubation, and mortality, ABO groups were not associated with risk of disease. Intubation and mortality rates were higher in patients with blood group B (OR: 2.93 p:0.390 95 % CI [0.253–33.9], OR: 0.217 p:0.211 95 % CI [0.020–2.37]) and Rh factor + (OR: 1.63 p:0.027 95 % CI [0.046–0.828]).

Risk Factors for Severe-Critical COVID-19 in Pregnant Women

Risk factors associated with severe-critical COVID-19 (coronavirus disease 2019) are based on findings in the general population. Pregnant women are at increased risk of severe-critical infection, and few reports are based on these women. A multicentric case-control study was conducted at the Mexican Institute of Social Security, State of Mexico, during the COVID-19 pandemic. We included pregnant women who were consecutively admitted to respiratory care units and were followed until 30 days after the resolution of pregnancy. A total of 758 pregnant women with a positive RT-PCR test for SARS-CoV-2 were enrolled from June 2020 to July 2021. We defined groups using the World Health Organization Severity Classification; cases were pregnant women with severe-critical COVID-19 (n = 123), and controls were subjects with non-severe COVID-19 (n = 635). Data was gathered from clinical files. A multivariate logistic regression analysis was used to adjust odds ratios and their 95% confidence intervals of factors associated with severe-critical COVID-19. Risk factors associated with severe-critical COVID-19 in pregnancy were non-vaccination (OR 10.18), blood type other than O (OR 6.29), maternal age > 35 years (OR 5.76), history of chronic hypertension (OR 5.12), gestational age at infection ≥ 31 weeks (OR 3.28), and multiparity (OR 2.80).

Impact of ABO Blood Group, Hematological, and Biochemical Abnormalities on Incidence of Patients Infected with COVID-19

This study aimed to investigate the relationship between blood types and COVID-19 susceptibility and explore changes in blood variables, as well as their relationship with the occurrence of COVID-19. SARS-CoV-2 is a pandemic that has affected people's health and the global financial system. Since the initial confirmed case of COVID-19, people have been influenced worldwide with varying manifestations. Moreover, researchers have illustrated a link between ABO blood types and COVID-19 susceptibility and incidence. Research has also shown that ABO blood groups might play a role in estimating COVID-19 susceptibility and death. Our analysis revealed that blood type O might probably reduce vulnerability to the SARS-CoV-2 illness. On the contrary, people with blood type A are at a higher risk of SARS-CoV-2 infection. This study also evaluated liver biomarkers among COVID-19 patients, revealing significant abnormalities in the levels of alanine amino transferees, aspartate amino transferees, gamma-glutamyl transferees, and total bilirubin.

Association of ABO blood types and clinical variables with COVID-19 infection severity in Libya

Objective

The continuing COVID-19 pandemic is a coronavirus-related health emergency (severe acute respiratory syndrome coronavirus 2). Inadequate efforts are still being made to address the illness situation in Libya, and this must change. To address these issues, we looked into the demography and trend of the disease as well as the potential risk factors for infection.

Methods

This study is a retrospective case-control study conducted online among 616 COVID-19 patients. The p_0.05 value, odds ratios, and 95% confidence intervals were calculated and analyzed from the drawn data.

Results

Males were at high risk of COVID-19 than females (odds ratio = 1.3, 95% confidence interval: 1.042-1.622; p = 0.02). Anosmia and ageusia were more prominent in females. Patients with an "AB" blood group are significantly susceptible to infection. Adults (31 and above) are highly liable to infection. The univariate logistic regression analysis revealed that smoking is a risk factor for those above 60 years (odds ratio = 2.228, 95% confidence interval: 1.145-4.336; p = 0.018). Individuals with chronic diseases such as diabetes and/or hypertension are more prone to COVID-19 (odds ratio = 10.045, 95% confidence interval: 3.078-32.794; p = 0.000 and odds ratio = 11.508, 95% confidence interval: 3.930-33.695; p = 0.000, respectively).

Conclusion

This study provided for the first time the demographic data and the trend of COVID-19 infection in Libya, which will assist the stakeholders and governmental bodies in planning protection strategies against the pandemic.

Analysis between ABO blood group and clinical outcomes in COVID-19 patients and the potential mediating role of ACE2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become the most common coronavirus that causes large-scale infections worldwide. Currently, several studies have shown that the ABO blood group is associated with coronavirus disease 2019 (COVID-19) infection and some studies have also suggested that the infection of COVID-19 may be closely related to the interaction between angiotensin-converting enzyme 2 (ACE2) and blood group antigens. However, the relationship between blood type to clinical outcome in critically ill patients and the mechanism of action is still unclear. The current study aimed to examine the correlation between blood type distribution and SARS-CoV-2 infection, progression, and prognosis in patients with COVID-19 and the potential mediating role of ACE2. With 234 patients from 5 medical centers and two established cohorts, 137 for the mild cohort and 97 for the critically ill cohort, we found that the blood type A population was more sensitive to SARS-CoV-2, while the blood type distribution was not relevant to acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and mortality in COVID-19 patients. Further study showed that the serum ACE2 protein level of healthy people with type A was significantly higher than that of other blood groups, and type O was the lowest. The experimental results of spike protein binding to red blood cells also showed that the binding rate of people with type A was the highest, and that of people with type O was the lowest. Our finding indicated that blood type A may be the biological marker for susceptibility to SARS-CoV-2 infection and may be associated with potential mediating of ACE2, but irrelevant to the clinical outcomes including ARDS, AKI, and death. These findings can provide new ideas for clinical diagnosis, treatment, and prevention of COVID-19.

Blood Type Associated with the Risk of COVID-19 Infection in Pregnant Women

COVID-19 forced us to investigate risk factors to provide the best medical attention, especially in vulnerable groups, such as pregnant patients. Studies in other populations have analyzed blood groups in relation to infection, complications, and death. The present study aimed to analyze the association of blood groups with the risk of infection and complications in pregnant women and newborns from the Mexican-Mestizo population. We studied 1906 individuals. Quantitative variables were analyzed through the Student’s t-test. Categorical variables were analyzed through Pearson’s chi-square test, and logistic regression was used to analyze the association between categorical variables and outcomes. No significant association was observed between blood groups and infection risk. Individuals with the AB blood type are at higher risk for developing severe disease, although blood groups do not seem to be involved in the risk of SARS-CoV-2 infection. However, the AB blood group could be considered a risk factor for developing severe COVID-19 in the Mexican population.

ABO Blood Groups and Incidence of COVID-19 in the Mass Gathering Events in Borriana (Spain), March 2020: A Retrospective Cohort Study

Our objective was to estimate the incidence of COVID-19 and the ABO blood Groups in the mass-gathering events (MGEs) during the Falles Festival in Borriana (Spain) from 6-10 March 2020. We conducted a population-based retrospective cohort study and measured anti-SARS-CoV-2 antibodies and the ABO of participants. We performed laboratory COVID-19 tests and obtained the ABO in 775 subjects (72.8% of the original exposed cohort): O-group (45.2%), A-group (43.1%), B-group (8.5%) and AB-group (3.4%). Adjusted for confounding factors, including COVID-19 exposure during the MGEs, attack rates of COVID-19 for each ABO group were 55.4%, 59.6%, 60.2%, and 63.7%. The adjusted relative risks were for O-group 0.93 (95% Confidence Interval [CI] 0.83-1.04), for A-group 1.06 (95% CI 0.94-1.18), for B-group 1.04 (95%CI 0.88-1.24), and for AB-group 1.11 (95% CI 0.81-1.51) with no significant differences. Conclusions: Our results suggest no effect of ABO on COVID-19 incidence. We observed weak but not significant protection of the O-group and not a significantly greater infection risk for the remaining groups compared with the O-group. More studies are needed to resolve the controversies regarding the association between ABO and COVID-19.

A large cohort study of the effects of Lewis, ABO, 13 other blood groups, and secretor status on COVID-19 susceptibility, severity, and long COVID-19

BACKGROUND

Previous studies have reported Blood type O to confer a lower risk of SARS-CoV-2 infection, while secretor status and other blood groups have been suspected to have a similar effect as well.

STUDY DESIGN AND METHODS

To determine whether any other blood groups influence testing positive for SARS-CoV-2, COVID-19 severity, or prolonged COVID-19, we used a large cohort of 650,156 Danish blood donors with varying available data for secretor status and blood groups ABO, Rh, Colton, Duffy, Diego, Dombrock, Kell, Kidd, Knops, Lewis, Lutheran, MNS, P1PK, Vel, and Yt. Of these, 36,068 tested positive for SARS-CoV-2 whereas 614,088 tested negative between 2020-02-17 and 2021-08-04. Associations between infection and blood groups were assessed using logistic regression models with sex and age as covariates.

RESULTS

The Lewis blood group antigen Le^a displayed strongly reduced SARS-CoV-2 susceptibility OR 0.85 CI[0.79-0.93] p < .001. Compared to blood type O, the blood types B, A, and AB were found more susceptible toward infection with ORs 1.1 CI[1.06-1.14] p < .001, 1.17 CI[1.14-1.2] p < .001, and 1.2 CI[1.14-1.26] p < .001, respectively. No susceptibility associations were found for the other 13 blood groups investigated. There was no association between any blood groups and COVID-19 hospitalization or long COVID-19. No secretor status associations were found.

DISCUSSION

This study uncovers a new association to reduced SARS-CoV-2 susceptibility for Lewis type Le^a and confirms the previous link to blood group O. The new association to Le^a could be explained by a link between mucosal microbiome and SARS-CoV-2.

Genetic Variants and Protective Immunity against SARS-CoV-2

The novel coronavirus-19 (SARS-CoV-2), has infected numerous individuals worldwide, resulting in millions of fatalities. The pandemic spread with high mortality rates in multiple waves, leaving others with moderate to severe symptoms. Co-morbidity variables, including hypertension, diabetes, and immunosuppression, have exacerbated the severity of COVID-19. In addition, numerous efforts have been made to comprehend the pathogenic and host variables that contribute to COVID-19 susceptibility and pathogenesis. One of these endeavours is understanding the host genetic factors predisposing an individual to COVID-19. Genome-Wide Association Studies (GWAS) have demonstrated the host predisposition factors in different populations. These factors are involved in the appropriate immune response, their imbalance influences susceptibility or resistance to viral infection. This review investigated the host genetic components implicated at the various stages of viral pathogenesis, including viral entry, pathophysiological alterations, and immunological responses. In addition, the recent and most updated genetic variations associated with multiple host factors affecting COVID-19 pathogenesis are described in the study.

Glycosylation in SARS-CoV-2 variants: A path to infection and recovery

Glycan is an essential molecule that controls and drives life in a precise direction. The paucity of research in glycobiology may impede the significance of its role in the pandemic guidelines. The SARS-CoV-2 spike protein is heavily glycosylated, with 22 putative N-glycosylation sites and 17 potential O-glycosylation sites discovered thus far. It is the anchor point to the host cell ACE2 receptor, TMPRSS2, and many other host proteins that can be recognized by their immune system; hence, glycosylation is considered the primary target of vaccine development. Therefore, it is essential to know how this surface glycan plays a role in viral entry, infection, transmission, antigen, antibody responses, and disease progression. Although the vaccines are developed and applied against COVID-19, the proficiency of the immunizations is not accomplished with the current mutant variations. The role of glycosylation in SARS-CoV-2 and its receptor ACE2 with respect to other putative cell glycan receptors and the significance of glycan in host cell immunity in COVID-19 are discussed in this paper. Hence, the molecular signature of the glycan in the coronavirus infection can be incorporated into the mainstream therapeutic process.

ABO rs657152 and Blood Groups Are as Predictor Factors of COVID-19 Mortality in the Iranian Population

Several studies have discovered a relationship between specific blood types, genetic variations of the ABO gene, and coronavirus disease 2019 (COVID-19). Therefore, the aim of this study was to evaluate the association between ABO rs657152 polymorphisms and ABO blood groups with COVID-19 mortality. The tetraprimer amplification refractory mutation system, polymerase chain reaction method, was used for ABO rs657152 polymorphism genotyping in 1,211 dead and 1,442 improved patients. In the current study, the frequency of ABO rs657152 AA than CC genotypes was significantly higher in dead patients than in improved patients. Our findings indicated that blood type A was associated with the highest risk of COVID-19 mortality compared to other blood groups, and patients with blood type O have a lower risk of infection, suggesting that blood type O may be a protective factor against COVID-19 mortality. Multivariate logistic regression test indicated that higher COVID-19 mortality rates were linked with alkaline phosphatase, alanine aminotransferase, high density lipoprotein, low-density lipoprotein, fasting blood glucose, uric acid, creatinine, erythrocyte sedimentation rate, C-reactive protein, 25-hydroxyvitamin D, real-time PCR Ct values, ABO blood groups, and ABO rs657152 AA genotype. In conclusion, the AA genotype of ABO rs657152 and blood type A were associated with a considerably increased frequency of COVID-19 mortality. Further research is necessary to validate the obtained results.

ABO blood groups and the risk of SARS-CoV-2 infection

There is no doubt that genetic factors of the host play a role in susceptibility to infectious diseases. An association between ABO blood groups and SARS-CoV-2 infection as well as the severity of COVID-19 has been suggested relatively early during the pandemic and gained enormously high public interest. It was postulated that blood group A predisposes to a higher risk of infection as well as to a much higher risk of severe respiratory disease and that people with blood group O are less frequently and less severely affected by the disease. However, as to the severity of COVID-19, a thorough summary of the existing literature does not support these assumptions in general. Accordingly, at this time, there is no reason to suppose that knowledge of a patient's ABO phenotype should directly influence therapeutical decisions in any way. On the other hand, there are many data available supporting an association between the ABO blood groups and the risk of contracting SARS-CoV-2. To explain this association, several interactions between the virus and the host cell membrane have been proposed which will be discussed here.

Association Between ABO Blood Group System and COVID-19 Severity

OBJECTIVES

A possible association between blood group systems (ABO and Rh) and coronavirus disease 2019 (COVID-19) severity has recently been investigated by various studies with conflicting results. However, due to variations in the prevalence of the ABO and Rh blood groups in different populations, their association with COVID-19 might be varied as well. Therefore, we conducted this study on Libyan participants to further investigate this association and make population-based data available to the worldwide scientific community.

METHODS

In this case-control study, ABO and Rh blood groups in 419 confirmed COVID-19 cases in Zawia, Libya, and 271 healthy controls were compared using descriptive statistics and χ 2 tests.

RESULTS

Blood group A was significantly more prevalent in patients with severe COVID-19 (64/125; 51.2%) than in patients with nonsevere COVID-19 (108/294, 36.7%) (P < .034), whereas the O blood group prevalence was higher in nonsevere COVID-19 cases (131/294, 44.5%) compared with severe cases (43/125, 34.4%) (P < .001).

CONCLUSIONS

The results showed a significant association between blood group A and the severity of COVID-19, whereas patients with blood group O showed a low risk of developing severe COVID-19 infection. No significant association was found between Rh and susceptibility/severity of the disease.

Race may modify the association between blood type and COVID-19 infection

This study aims to investigate the race/ethnicity-specific association between blood type and COVID-19 susceptibility during March, 2020 and December, 2021 using data from the electronic health record at the University of Chicago Medicine. The study population was stratified into four groups: non-Hispanic White, non-Hispanic Black, Hispanic, and other. Log-binomial generalized mixed model was used to estimate the relative risk (RR) and 95% confidence interval (CI). When compared to blood type O, type B was associated with positive COVID-19 test in Blacks (RR = 1.12, 95% CI: 1.02-1.23), Whites (RR = 1.28, 95% CI: 0.99-1.66), and Hispanic (RR = 1.36, 95% CI: 0.97-1.92).

ABO Blood Group in Relation to COVID-19 Susceptibility and Clinical Outcomes: A Retrospective Observational Study in the United Arab Emirates

(1) Background: The association between ABO blood groups and COVID-19 outcomes was investigated in several studies. The results were controversial. This study aimed to explore the association between ABO blood groups and COVID-19 outcomes. (2) Methods: This retrospective study included 303 COVID-19 patients treated at the NMC Royal Hospital in the United Arab Emirates between 8 April 2020 and 30 June 2020. (3) Results: The mean age of patients included in the study was 39.3 ± 10.7 years, and 72.9% of patients were males. The prevalence of blood groups O, A, B, and AB was 40.3%, 27.7%, 25.1%, and 6.9%, respectively. The correlation between ABO blood groups and COVID-19 outcomes was insignificant except in the AB group, with significantly higher odds of disease severity. Increased age, higher body mass index (BMI), and being of male gender increased the risk for pneumonia among all blood groups. Both increased age and higher BMI increased the risk of mortality, and increased age increased the risk of disease severity. Troponin and platelet counts were significantly different in the A group compared to the non-A groups. Time to viral clearance was not different among blood groups. However, adjustment for Rh groups resulted in a significantly shorter time in the B group. (4) Conclusions: There was no significant association between ABO blood groups and COVID-19 outcomes, with the exception of group AB.

Rare Blood Groups in ABO, Rh, Kell Systems - Biological and Clinical Significance

Background: The frequency of ABO, Rh and Kell blood group antigens differs among populations of different ethnic ancestry. There are low-frequency antigens (<1%) and high-frequency antigens (>90%). A rare blood group is defined as the absence of a high-frequency antigen in the general population, as well as absence of multiple frequent antigens within a single or multiple blood group systems. Aim: To perform red blood cell typing and to calculate the antigen and phenotype frequencies, in order to identify rare blood group donors within the clinically most important АВО, Rh and Kell systems. Material and Methods: АВО, Rh (D, C, E, c, e) and Kell (K) antigen typing was performed using specific monoclonal sera and microplate technique, while Cellano (k) typing was performed with a monoclonal anti-k, antihuman globulin and column agglutination technique. Weak ABO subgroups were determined using the absorption elution method or molecular genotyping (PCR-SSP). Results: ABO antigen frequency is: A (40.89%), O (34.22%), B (16.97%), AB (7.92%) and weak ABO subgroups (0, 009 %). The established genotypes were AxO1 (0, 0026%) and AxB (0, 001%). Rh antigen frequency is: D (85.79%), C (71.7%), c (76.0%), E (26.0%) and е (97.95%). The most common Rh pheno-type is the DCcee (32.7%) while the rarest phenotype is the DCCEE phenotype (0. 003%). The prevalence of K and k antigen is 7.5% and 99.94%, respectively. The frequency of the rare phenotype K+k- is 0.06%. Conclusion: Large scale phenotyping of blood group antigens enables the identification of blood donors with rare blood groups for patients with rare phenotypes or with antibodies to high-frequency antigens and to frequent antigens within one or more blood group systems.

A Pilot Study on COVID-19 Positive Subjects: An Excerpt of Post-Infection-Pro-Diabetic Disposition & Related Consequences in Correlation to Hepato-Pancreatic Bio-Markers, Pro-Inflammatory Cytokines and Other Risk Factors

COVID-19, a global pandemic that led to increased morbidity and mortality worldwide since its outcome at the end of the year 2019. A newly discovered variant of severe acute respiratory distress syndrome coronavirus-2 (SARS-CoV-2) was the arbitrator for spreading the syndrome by droplet transmission causing multi-organ failure in many occasions. A post-infection-pro-diabetic disposition was found evident in this study with the persistence of hepato-pancreatic aberrations in respect of reference range of tissue specific bio-markers in hospital admitted COVID-19 cases. The results of this study show that hyperglycemia is a risk factor in precipitating disease oriented complications to the patients with COVID-19 disease. A post-infection follow- up on glycemic-index and related complexities is a vital need to the COVID-19 infected convalescent subjects. Implementation of guidelines on social measure and awareness of anti-viral interventions may be the only way to prevent COVID-19 transmission.

Role of the AB0 blood group in COVID-19 infection and complications: A population-based study

Since the beginning of the COVID-19 pandemic, the ABO blood group has been described as a possible biological marker of susceptibility for the disease. This study evaluates the role of ABO group on the risk of SARS-CoV-2 infection and related complications in a population-based cohort including 87,090 subjects from the Navarre population (Northern Spain) with no history of SARS-CoV-2 infection and with known ABO blood group, after one year of the pandemic (May 2020 - May 2021). The risk of infection, hospitalization, Intensive Care Unit (ICU) admission and death was analyzed using multivariate logistic regression, adjusting for possible confounding variables. A lower risk of infection was observed in group 0 vs non-0 groups [OR 0.94 (95 %CI 0.90-0.99)], a higher risk of infection in group A vs non-A groups [OR 1.09 (95 %CI 1.04-1.15)] and a higher risk of infection in group A vs group 0 [OR 1.08 (95CI 1.03-1.14)] (when the 4 groups are analyzed separately). No association was observed between blood groups and hospitalization, ICU admission, or death in SARS-CoV-2 infected subjects. Regarding the risk of SARS-CoV-2 infection, we observed a protective role of group O and a greater risk in the A group.

Association of ABO blood group with susceptibility to SARS-CoV-2 infection in Rupandehi district of Nepal

Objectives:

Recent studies after the outbreak of coronavirus disease 2019 have shown an association of the ABO blood group to the susceptibility of severe acute respiratory syndrome coronavirus 2 infection. Anti-A and anti-B antibodies, carbohydrate clustering, interleukin-6 levels and host transmembrane protease serine subtype 2 were suggested to cause the variable susceptibility of severe acute respiratory syndrome coronavirus 2 infection to the ABO blood groups. This study aims to find the association of the ABO blood group with severe acute respiratory syndrome coronavirus 2 infection susceptibility in Nepal.

Methods:

Population-based matched case–control study was conducted from October 2021 to February 2022 in Rupandehi district of Nepal. A total of 1091 reverse transcription-polymerase chain reaction confirmed coronavirus disease 2019 cases and 2182 controls were included in the study by convenient sampling method.

Results:

A statistically significant association of severe acute respiratory syndrome coronavirus 2 infection was observed for the blood group AB between cases and controls (11.5% vs 8.5%; odds ratio = 1.4, 95% confidence interval = 1.10–1.78). However, there was no association of severe acute respiratory syndrome coronavirus 2 infection for blood group A (26.7% vs 28.23%; odds ratio = 0.93, 95% confidence interval = 0.79–1.09), B (26.9% vs 29.84%; odds ratio = 0.86, 95% confidence interval = 0.73–1.02) and O (34.9% vs 33.41%; odds ratio = 1.07, 95% confidence interval = 0.92–1.25).

Conclusion:

This study reported slightly more susceptibility to severe acute respiratory syndrome coronavirus 2 infection among individuals with blood group AB.

The rs8176740 T/A and rs512770 T/C Genetic Variants of the ABO Gene Increased the Risk of COVID-19, as well as the Plasma Concentration Platelets

We conducted a case-control study in order to evaluate whether ABO gene polymorphisms were associated with a high risk of developing COVID-19 in a cohort of patients. Six ABO gene polymorphisms (rs651007 T/C, rs579459 T/C, rs495828 T/G, rs8176746 A/C, rs8176740 T/A, and rs512770 T/C) were determined using TaqMan genotyping assays in a group of 415 COVID-19 patients and 288 healthy controls. The distribution of rs651007 T/C, rs579459 T/C, rs495828 T/G, and rs8176746 A/C polymorphisms was similar in patients and healthy controls. Nonetheless, under co-dominant (OR = 1.89, pC_Co-dominant = 6 × 10⁻⁶), recessive (OR = 1.98, pC_Recessive = 1 × 10⁻⁴), and additive (OR = 1.36, pC_Additive = 3 × 10⁻³) models, the TT genotype of the rs8176740 T/A polymorphism increased the risk of developing COVID-19. In the same way, under co-dominant, recessive, and additive models, the TT genotype of the rs512770 T/C polymorphism was associated with a high risk of developing COVID-19 (OR = 1.87, pC_Co-dominant = 2 × 10⁻³; OR = 1.87, pC_Recessive = 5 × 10⁻⁴; and OR = 1.35, pC_Additive = 4 × 10⁻³, respectively). On the other hand, the GTC and GAT haplotypes were associated with a high risk of COVID-19 (OR = 5.45, pC = 1 × 10⁻⁶ and OR = 6.33, pC = 1 × 10⁻⁶, respectively). In addition, the rs8176740 TT genotype was associated with high-platelet plasma concentrations in patients with COVID-19. Our data suggested that the ABO rs512770 T/C and rs8176740 T/A polymorphisms increased the risk of developing COVID-19 and the plasma concentration of platelets.

Use of Early Donated COVID-19 Convalescent Plasma Is Optimal to Preserve the Integrity of Lymphatic Endothelial Cells

Convalescent plasma therapy (CPT) has gained significant attention since the onset of the coronavirus disease 2019 (COVID-19) pandemic. However, clinical trials designed to study the efficacy of CPT based on antibody concentrations were inconclusive. Lymphatic transport is at the interplay between the immune response and the resolution of inflammation from peripheral tissues, including the artery wall. As vascular complications are a key pathogenic mechanism in COVID-19, leading to inflammation and multiple organ failure, we believe that sustaining lymphatic vessel function should be considered to define optimal CPT. We herein sought to determine what specific COVID-19 convalescent plasma (CCP) characteristics should be considered to limit inflammation-driven lymphatic endothelial cells (LEC) dysfunction. CCP donated 16 to 100 days after the last day of symptoms was characterized and incubated on inflammation-elicited adult human dermal LEC (aHDLEC). Plasma analysis revealed that late donation correlates with higher concentration of circulating pro-inflammatory cytokines. Conversely, extracellular vesicles (EVs) derived from LEC are more abundant in early donated plasma (r = −0.413, p = 0.004). Thus, secretion of LEC-EVs by an impaired endothelium could be an alarm signal that instigate the self-defense of peripheral lymphatic vessels against an excessive inflammation. Indeed, in vitro experiments suggest that CCP obtained rapidly following the onset of symptoms does not damage the aHDLEC junctions as much as late-donated plasma. We identified a particular signature of CCP that would counteract the effects of an excessive inflammation on the lymphatic endothelium. Accordingly, an easy and efficient selection of convalescent plasma based on time of donation would be essential to promote the preservation of the lymphatic and immune system of infected patients.

The Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) Pandemic: Are Africa's Prevalence and Mortality Rates Relatively Low?

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the cause of coronavirus disease 19 (COVID-19), has been rapidly spreading since December 2019, and within a few months, it turned out to be a global pandemic. The disease affects primarily the lungs, but its pathogenesis spreads to other organs as well. However, its mortality rates vary, and in the majority of infected people, there are no serious consequences. Many factors including advanced age, preexisting health conditions, and genetic predispositions are believed to exacerbate outcomes of COVID-19. The virus contains several structural proteins including the spike (S) protein with subunits for binding, fusion, and internalization into host cells following interaction with host cell receptors and proteases (ACE2 and TMPRSS2, respectively) to cause the subsequent pathology. Although the pandemic has spread into all countries, most of Africa is thought of as having relatively less prevalence and mortality. Several hypotheses have been forwarded as reasons for this and include warmer weather conditions, vaccination with BCG (i.e., trained immunity), and previous malaria infection. From genetics or metabolic points of view, it has been proposed that most African populations could be protected to some degree because they lack some genetic susceptibility risk factors or have low-level expression of allelic variants, such as ACE2 and TMPRSS2 that are thought to be involved in increased infection risk or disease severity. The frequency of occurrence of α-1 antitrypsin (an inhibitor of a tissue-degrading protease, thereby protecting target host tissues including the lung) deficiency is also reported to be low in most African populations. More recently, infections in Africa appear to be on the rise. In general, there are few studies on the epidemiology and pathogenesis of the disease in African contexts, and the overall costs and human life losses due to the pandemic in Africa will be determined by all factors and conditions interacting in complex ways.

A global effort to dissect the human genetic basis of resistance to SARS-CoV-2 infection

SARS-CoV-2 infections display tremendous interindividual variability, ranging from asymptomatic infections to life-threatening disease. Inborn errors of, and autoantibodies directed against, type I interferons (IFNs) account for about 20% of critical COVID-19 cases among SARS-CoV-2-infected individuals. By contrast, the genetic and immunological determinants of resistance to infection per se remain unknown. Following the discovery that autosomal recessive deficiency in the DARC chemokine receptor confers resistance to Plasmodium vivax, autosomal recessive deficiencies of chemokine receptor 5 (CCR5) and the enzyme FUT2 were shown to underlie resistance to HIV-1 and noroviruses, respectively. Along the same lines, we propose a strategy for identifying, recruiting, and genetically analyzing individuals who are naturally resistant to SARS-CoV-2 infection.

COVID-19, Cation Dysmetabolism, Sialic Acid, CD147, ACE2, Viroporins, Hepcidin and Ferroptosis: A Possible Unifying Hypothesis

Background: iron and calcium dysmetabolism, with hyperferritinemia, hypoferremia, hypocalcemia and anemia have been documented in the majority of COVID-19 patients at later/worse stages. Furthermore, complementary to ACE2, both sialic acid (SA) molecules and CD147 proved relevant host receptors for SARS-CoV-2 entry, which explains the viral attack to multiple types of cells, including erythrocytes, endothelium and neural tissue. Several authors advocated that cell ferroptosis may be the core and final cell degenerative mechanism. Methods: a literature research was performed in several scientific search engines, such as PubMed Central, Cochrane Library, Chemical Abstract Service. More than 500 articles were retrieved until mid-December 2021, to highlight the available evidence about the investigated issues. Results: based on COVID-19 literature data, we have highlighted a few pathophysiological mechanisms, associated with virus-based cation dysmetabolism, multi-organ attack, mitochondria degeneration and ferroptosis. Our suggested elucidated pathological sequence is: a) spike protein subunit S1 docking with sialylated membrane glycoproteins/receptors (ACE2, CD147), and S2 subunit fusion with the lipid layer; b) cell membrane morpho-functional changes due to the consequent electro-chemical variations and viroporin action, which induce an altered ion channel function and intracellular cation accumulation; c) additional intracellular iron concentration due to a deregulated hepcidin-ferroportin axis, with higher hepcidin levels. Viral invasion may also affect erythrocytes/erythroid precursors, endothelial cells and macrophages, through SA and CD147 receptors, with relative hemoglobin and iron/calcium dysmetabolism. AB0 blood group, hemochromatosis, or environmental elements may represent possible factors which affect individual susceptibility to COVID-19.     Conclusions: our literature analysis confirms the combined role of SA molecules, ACE2, CD147, viroporins and hepcidin in determining the cation dysmetabolism and final ferroptosis in the cells infected by SARS-CoV-2. The altered ion channels and electrochemical gradients of the cell membrane have a pivotal role in the virus entry and cell dysmetabolism, with subsequent multi-organ immune-inflammatory degeneration and erythrocyte/hemoglobin alterations.

COVID-19, Cation Dysmetabolism, Sialic Acid, CD147, ACE2, Viroporins, Hepcidin and Ferroptosis: A Possible Unifying Hypothesis

Background: iron and calcium dysmetabolism, with hyperferritinemia, hypoferremia, hypocalcemia and anemia have been documented in the majority of COVID-19 patients at later/worse stages. Furthermore, complementary to ACE2, both sialic acid (SA) molecules and CD147 proved relevant host receptors for SARS-CoV-2 entry, which explains the viral attack to multiple types of cells, including erythrocytes, endothelium and neural tissue. Several authors advocated that cell ferroptosis may be the core and final cell degenerative mechanism. Methods: a literature research was performed in several scientific search engines, such as PubMed Central, Cochrane Library, Chemical Abstract Service. More than 500 articles were retrieved until mid-December 2021, to highlight the available evidence about the investigated issues. Results: based on COVID-19 literature data, we have highlighted a few pathophysiological mechanisms, associated with virus-based cation dysmetabolism, multi-organ attack, mitochondria degeneration and ferroptosis. Our suggested elucidated pathological sequence is: a) spike protein subunit S1 docking with sialylated membrane glycoproteins/receptors (ACE2, CD147), and S2 subunit fusion with the lipid layer; b) cell membrane morpho-functional changes due to the consequent electro-chemical variations and viroporin action, which induce an altered ion channel function and intracellular cation accumulation; c) additional intracellular iron concentration due to a deregulated hepcidin-ferroportin axis, with higher hepcidin levels. Viral invasion may also affect erythrocytes/erythroid precursors, endothelial cells and macrophages, through SA and CD147 receptors, with relative hemoglobin and iron/calcium dysmetabolism. AB0 blood group, hemochromatosis, or environmental elements may represent possible factors which affect individual susceptibility to COVID-19.     Conclusions: our literature analysis confirms the combined role of SA molecules, ACE2, CD147, viroporins and hepcidin in determining the cation dysmetabolism and final ferroptosis in the cells infected by SARS-CoV-2. The altered ion channels and electrochemical gradients of the cell membrane have a pivotal role in the virus entry and cell dysmetabolism, with subsequent multi-organ immune-inflammatory degeneration and erythrocyte/hemoglobin alterations.

ABO Blood Group Incompatibility Protects Against SARS-CoV-2 Transmission

ABO blood groups appear to be associated with the risk of SARS-CoV-2 infection, but the underlying mechanisms and their real importance remain unclear. Two hypotheses have been proposed: ABO compatibility-dependence (neutralization by anti-ABO antibodies) and ABO-dependent intrinsic susceptibility (spike protein attachment to histo-blood group glycans). We tested the first hypothesis through an anonymous questionnaire addressed to hospital staff members. We estimated symptomatic secondary attack rates (SAR) for 333 index cases according to spouse ABO blood group compatibility. Incompatibility was associated with a lower SAR (28% vs. 47%; OR 0.43, 95% CI 0.27–0.69), but no ABO dependence was detected in compatible situations. For the second hypothesis, we detected no binding of recombinant SARS-CoV-2 RBD to blood group-containing glycans. Thus, although no intrinsic differences in susceptibility according to ABO blood type were detected, ABO incompatibility strongly decreased the risk of COVID-19 transmission, suggesting that anti-ABO antibodies contribute to virus neutralization.

Role of Genetic Variants and Host Polymorphisms on COVID‐19: From Viral Entrance Mechanisms to Immunological Reactions

Coronavirus disease 2019 (COVID‐19), caused by a highly pathogenic emerging virus, is called severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Knowledge regarding the pathogenesis of this virus is in infancy; however, investigation on the pathogenic mechanisms of the SARS‐CoV‐2 is underway. In COVID‐19, one of the most remarkable characteristics is the wide range of disease manifestation and severity seen across individuals of different ethnic backgrounds and geographical locations. To effectively manage COVID‐19 in the populations, beyond SARS‐CoV‐2 detection, serological response assessment, and analytic techniques, it is critical to obtain knowledge about at‐risk individuals and comprehend the identified variations in the disease's severity in general and also in the populations' levels. Several factors can contribute to variation in disease presentation, including population density, gender and age differences, and comorbid circumstances including diabetes mellitus, hypertension, and obesity. Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility. Besides this, COVID‐19 has also been linked with a higher risk of mortality in men and certain ethnic groups, revealing that host genetic characteristics may affect the individual risk of death. Also, genetic variants involved in pathologic processes, including virus entrance into cells, antiviral immunity, and inflammatory response, are not entirely understood. Regarding SARS‐CoV‐2 infection characteristics, the present review suggests that various genetic polymorphisms influence virus pathogenicity and host immunity, which might have significant implications for understanding and interpreting the matter of genetics in SARS‐CoV‐2 pathogenicity and customized integrative medical care based on population investigation.

Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility.

Genetic variants were involved in the pathologic processes of SARS‐CoV‐2 infection.

Various genetic polymorphisms influence virus pathogenicity and host immunity.

Human leukocyte antigens (HLAs) may play a vital role in SARS‐CoV‐2 susceptibility.

Polymorphisms in several genes such as IL‐6, TMPRSS2, IFITM3, CD26, ACE, and DBP were associated with the COVID‐19 severity.

Viral and Host Genetic and Epigenetic Biomarkers Related to SARS-CoV-2 Cell Entry, Infection Rate, and Disease Severity

The rapid spread of COVID-19 outbreak lead to a global pandemic declared in March 2020. The common features of corona virus family helped to resolve structural characteristics and entry mechanism of SARS-CoV-2. However, rapid mutagenesis leads to the emergence of new strains that may have different reproduction rates or infectivity and may impact the course and severity of the disease. Host related factors may also play a role in the susceptibility for infection as well as the severity and outcomes of the COVID-19. We have performed a literature and database search to summarize potential viral and host-related genomic and epigenomic biomarkers, such as genetic variability, miRNA, and DNA methylation in the molecular pathway of SARS-CoV-2 entry into the host cell, that may be related to COVID-19 susceptibility and severity. Bioinformatics tools may help to predict the effect of mutations in the spike protein on the binding to the ACE2 receptor and the infectivity of the strain. SARS-CoV-2 may also target several transcription factors and tumour suppressor genes, thus influencing the expression of different host genes and affecting cell signalling. In addition, the virus may interfere with RNA expression in host cells by exploiting endogenous miRNA and its viral RNA. Our analysis showed that numerous human miRNA may form duplexes with different coding and non-coding regions of viral RNA. Polymorphisms in human genes responsible for viral entry and replication, as well as in molecular damage response and inflammatory pathways may also contribute to disease prognosis and outcome. Gene ontology analysis shows that proteins encoded by such polymorphic genes are highly interconnected in regulation of defense response. Thus, virus and host related genetic and epigenetic biomarkers may help to predict the course of the disease and the response to treatment.

ABO blood group does not influence the level of anti-SARS-CoV-2 antibodies in convalescent plasma donors

BACKGROUND

The association of the ABO blood group with COVID-19 disease has been confirmed by several studies, with the blood group A patients being more susceptible and prone to a more severe clinical course of the disease. Additionally, several authors also addressed the association of ABO-types and the levels of anti-SARS-CoV-2 antibodies in convalescents, mostly supporting a theory that the non-O blood group convalescents present with higher levels of anti-SARS-CoV-2 antibodies.

STUDY DESIGN AND METHODS

Since previous findings were based on small convalescent cohorts, we quantified the anti-SARS-CoV-2 antibody levels in total 3187 convalescent plasma donors with three commercial serological and one standard neutralizing antibody test. The majority of donors had undergone a mild form of the disease and the median time of sampling was 66 days after diagnosis.

RESULTS

None of the antibody quantitation results showed any significant association with the ABO blood group types. The same result was evident in the subgroup of vaccinated individuals (n=370) and the subgroups when stratified according to post-COVID-19 periods (0-60, 60-120, and 120-180 days).

CONCLUSION

In conclusion, we found no evidence to confirm that the ABO blood group types influence the level of SARS-CoV-2 antibody response in COVID-19 convalescent plasma donors.

Allelic Variants Within the ABO Blood Group Phenotype Confer Protection Against Critical COVID-19 Hospital Presentation

Introduction: Coronavirus disease 2019 (COVID-19) disease severity differs widely due to numerous factors including ABO gene-derived susceptibility or resistance. The objective of this study was to investigate the association of the ABO blood group and genetic variations of the ABO gene with COVID-19 severity in a heterogeneous hospital population sample from the United Arab Emirates, with the use of an epidemiological and candidate gene approach from a genome-wide association study (GWAS). Methods: In this cross-sectional study, a total of 646 participants who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were recruited from multiple hospitals and population-based (quarantine camps) recruitment sites from March 2020 to February 2021. The participants were divided into two groups based on the severity of COVID-19: noncritical (n = 453) and critical [intensive care unit (ICU) patients] (n = 193), as per the COVID-19 Reporting and Data System (CO-RADS) classification. The multivariate logistic regression analysis demonstrated the association of ABO blood type as well as circulating anti-A antibodies and anti-B antibodies as well as A and B antigens, in association with critical COVID-19 hospital presentation. A candidate gene analysis approach was conducted from a GWAS where we examined 240 single nucleotide polymorphisms (SNPs) (position in chr9: 136125788-136150617) in the ABO gene, in association with critical COVID-19 hospital presentation. Results: Patients with blood group O [odds ratio (OR): 0.51 (0.33, 0.79); p = 0.003] were less likely to develop critical COVID-19 symptoms. Eight alleles have been identified to be associated with a protective effect of blood group O in ABO 3'untranslated region (UTR): rs199969472 (p = 0.0052), rs34266669 (p = 0.0052), rs76700116 (p = 0.0052), rs7849280 (p = 0.0052), rs34039247 (p = 0.0104), rs10901251 (p = 0.0165), rs9411475 (p = 0.0377), and rs13291798 (p = 0.0377). Conclusion: Our findings suggest that there are novel allelic variants that link genetic variants of the ABO gene and ABO blood groups contributing to the reduced risk of critical COVID-19 disease. This study is the first study to combine genetic and serological evidence of the involvement of the ABO blood groups and the ABO gene allelic associations with COVID-19 severity within the Middle Eastern population.

Risk factors for oxygen requirement in hospitalized pregnant and postpartum women with COVID-19

OBJECTIVE

To identify risk factors for Oxygen (O₂) needs in pregnant and postpartum women with COVID-19.

METHODS

Prospective cohort involving pregnant women hospitalized with COVID-19 from April to October 2020. The oxygen need was analyzed regarding risk factors: demographic characteristics, clinical and laboratory parameters at hospital admission, and chest Computer Tomography (CT) findings. Poisson univariate analysis was used to estimate the Relative Risk (RR) and 95% Confidence Intervals.

RESULTS

145 patients, 80 who used and 65 who did not use O₂, were included. Body mass index ≥ 30, smoking, and chronic hypertension increased the risk of O₂ need by 1.86 (95% CI 1.10-3.21), 1.57 (95% CI 1.16‒2.12), and 1.46 (95% CI 1.09‒1.95), respectively. Patients who were hospitalized for COVID-19 and for obstetric reasons had 8.24 (95% CI 2.8‒24.29) and 3.44 (95% CI 1.05‒11.31) times more use of O₂ than those admitted for childbirth and abortion. Respiratory rate ≥ 24 breaths/min and O₂ saturation < 95% presented RR for O₂ requirements of 2.55 (1.82‒3.56) and 1.68 (95% CI 1.27-2.20), respectively. Ground Glass (GG) < 50% and with GG ≥ 50%, the risk of O₂ use were respectively 3.41-fold and 5.33-fold higher than in patients who haven't viral pneumonia on CT. The combination of C-reactive protein ≥ 21 mg/L, hemoglobin < 11.0 g/dL, and lymphopenia < 1500 mm³ on hospital admission increased the risk of O₂ use by 4.97-times.

CONCLUSIONS

In obstetric patients, clinical history, laboratory, clinical and radiological parameters at admission were identified as a risk for O₂ need, selecting the population with the greatest chance of worsening.

ABO blood groups and risk of human immunodeficiency virus infection: A systematic review and meta-analysis

The last few decades have seen a pandemic of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), which continues to cause substantial morbidity and mortality. ABO blood groups are anthropological and genetic characteristics of a population whose associations with HIV infection are still controversial. This systematic review with meta-analysis was undertaken to investigate whether certain blood groups may have associations with HIV infection. PubMed, Scopus and Web of Science databases were systematically searched as of 6 September 2021. Grey literature was identified through screening Google Scholar, and reference lists of relevant studies. All observational studies providing data on ABO blood group distribution among HIV-infected and uninfected participants were included. Using a random effect model, risk ratios (RR) and 95% confidence intervals (CIs) were pooled to quantify this relationship. Fifty eligible studies with a total of 3,068,244 participants and 6508 HIV-infected cases were included. The overall analysis found that blood group AB increased the risk of HIV infection by 19% as compared with non-AB blood groups (RR = 1.19, 95% CI: 1.03-1.39, p = 0.02). Pooled estimates for other blood groups failed to reach statistical significance. Subgroup analyses identified a positive relationship between AB blood group and HIV infection within Asia, patient populations (as opposed to blood donors and general populations), studies with lower sample sizes, high-income countries and studies with a moderate quality score. The sequential omission and re-analysis of studies within sensitivity analyses produced no change in the overall pooled effect. In conclusion, this study identified that blood group AB carriers were more susceptible to HIV infection. Future investigations should be directed toward clarification of the exact role of ABO blood groups in HIV infection and the possible underlying mechanisms.

ABO Blood Groups and the Incidence of Complications in COVID-19 Patients: A Population-Based Prospective Cohort Study

After a COVID-19 outbreak in the Falles festival of Borriana (Spain) during March 2020, a cohort of patients were followed until October 2020 to estimate complications post-COVID-19, considering ABO blood groups (ABO). From 536 laboratory-confirmed cases, 483 completed the study (90.1%) carried by the Public Health Center of Castelló and the Emergency and Microbiology and Clinical Analysis of Hospital de la Plana Vila-real. The study included ABO determination and telephone interviews of patients. The participants had a mean age of 37.2 ± 17.1 years, 300 females (62.1%). ABO were O (41.4%), A (45.5%), B (9.1%), and AB (3.9%). We found no difference in the incidence of COVID-19 infections. A total of 159 (32.9%) patients reported one or more post-COVID-19 complications with divergent incidences after adjustment: O (32.3%), A (32.6%), B (54.1%), and AB (27.6%); B groups had more complications post-COVID-19 when compared with O group (adjusted relative risk [aRR] 95% confidence interval [CI] 1.68, 95% CI 1.24–2.27), and symptoms of fatigue (1.79, 95% CI 1.08–2.95), myalgia (2.06, 95% CI 1.10–3.84), headache (2.61, 95% CI 1.58–4.31), and disorder of vision (4.26 95% CI 1.33–13.60). In conclusion, we observed significant differences in post-COVID-19 complications by ABO, with a higher incidence in B group. Additional research is justified to confirm our results.

Challenges in the Application of Glyco-Technology to Hepatitis B Virus Therapy and Diagnosis

Hepatitis B virus (HBV) is a major pathogen that causes acute/chronic hepatitis. Continuous HBV infection can lead to the development of hepatocellular carcinoma (HCC). Although several different anti-HBV treatments are available for chronic hepatitis B patients, discontinuing these medications is difficult. Patients with chronic hepatitis B at high risk for HCC therefore require close observation. However, no suitable biomarkers for detecting high-risk groups for HCC exist, except for serum HBV-DNA, but a number of HCC biomarkers are used clinically, such as alpha-fetoprotein (AFP) and protein induced by vitamin K absence-II (PIVKA-II). Glycosylation is an important post-translational protein modification involved in many human pathologic conditions. HBV surface proteins contain various oligosaccharides, and several reports have described their biological functions. Inhibition of HBV glycosylation represents a potential novel anti-HBV therapy. It is thought that glycosylation of hepatocytes/hepatoma cells is also important for HBV infection, as it prevents HBV from infecting cells other than hepatocytes, even if the cells express the HBV receptor. In this review, we summarize considerable research regarding the relationship between HBV and glycosylation as it relates to the development of novel diagnostic tests and therapies for HBV.

Association between blood groups and COVID-19 outcome in Iranian patients

Aim: Many factors have been speculated to explain the COVID-19 complex clinical phenotype. Due to the inconsistent data published on blood groups and COVID-19, we conducted a study on Iranian patients to further assess this association. Materials & methods: This retrospective study was conducted on data collected from confirmed COVID-19 hospitalized patients during March and December 2020 in a referral hospital for COVID-19, 5 Azar Hospital, Gorgan, north of Iran. A total of 1554 confirmed COVID-19 cases were enrolled in the study with blood group (ABO and Rh), demographic, and clinical data available. Results: Of 1554 patients, 1267 and 287 cases had recovered and deceased (due to COVID-19) outcomes, respectively. Most of the cases had O+ (29.6%), the least number had AB- (0.5%), and most of the deceased cases had O+ blood types (31.4%). Logistic regression analysis revealed that groups A- and B- had higher and groups B+, AB+, O+ and O- had lower odds of death than the A+ group. Conclusion: This study indicates that blood types may be related to the clinical outcome of COVID-19. Further studies with a large cohort for multiple people are required to validate this association.

Comprehensive Survey of Using Machine Learning in the COVID-19 Pandemic

Since December 2019, the global health population has faced the rapid spreading of coronavirus disease (COVID-19). With the incremental acceleration of the number of infected cases, the World Health Organization (WHO) has reported COVID-19 as an epidemic that puts a heavy burden on healthcare sectors in almost every country. The potential of artificial intelligence (AI) in this context is difficult to ignore. AI companies have been racing to develop innovative tools that contribute to arm the world against this pandemic and minimize the disruption that it may cause. The main objective of this study is to survey the decisive role of AI as a technology used to fight against the COVID-19 pandemic. Five significant applications of AI for COVID-19 were found, including (1) COVID-19 diagnosis using various data types (e.g., images, sound, and text); (2) estimation of the possible future spread of the disease based on the current confirmed cases; (3) association between COVID-19 infection and patient characteristics; (4) vaccine development and drug interaction; and (5) development of supporting applications. This study also introduces a comparison between current COVID-19 datasets. Based on the limitations of the current literature, this review highlights the open research challenges that could inspire the future application of AI in COVID-19.