Association between ABO blood groups and COVID-19 infection, severity and demise: A systematic review and meta-analysis

COVID-19 and blood group-related antigens: can natural anti-carbohydrate antibodies provide innate protection from symptomatic SARS-CoV-2 infection?

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) primarily targets respiratory mucosa, causing coronavirus disease 2019 (COVID-19). Susceptibility and severity of COVID-19 may be influenced by predisposing factors including blood groups. In this study, we investigated whether natural anti-carbohydrate antibodies provide innate protection against SARS-CoV-2 and influence disease severity.

Methodology

We used samples (plasma and saliva) from a longitudinal cohort study in Bangladesh that enrolled 100 COVID-19 symptomatic and asymptomatic patients. We also enrolled 21 and 38 healthy controls during the pandemic period and pre-pandemic period, respectively. We phenotype ABO blood grouping from blood and determined Lewis and secretor status (H antigen) from the saliva samples. We quantified natural anti-carbohydrate antibodies (anti-A, anti-B, anti-Tn-Mono and anti-αGal IgG, IgA, and IgM) from plasma collected at enrollment. We also explored the trend of natural anti-carbohydrate antibodies until 3 months of convalescence period among the COVID-19 patients (day 14 and day 90 from enrollment). Antibody quantification and ABH/Lewis phenotyping were performed using enzyme-linked immunosorbent assay (ELISA).

Results

We included 99 COVID-19 patients and 59 healthy controls assessing the differences of natural antibody titer during enrollment, while 95 patients were analyzed exploring Lewis and secretor status with natural antibody titer and disease status. We did not find significant difference in the distribution for neither ABO blood groups nor non-secretors and Lewis-negative individuals among asymptomatic or symptomatic patients and healthy controls. Nonetheless, we observed lower anti-A antibody titers among symptomatic patients compared to healthy controls. We also identified slight differences in antibody titers linked to age and gender. Anti-A and anti-B antibodies among asymptomatic patients had a higher trend up to 3 months from infection compared to symptomatic patients.

Conclusion

Higher natural anti-A and anti-B antibody titers may offer protection against symptomatic COVID-19 infections. Gender and blood group differences indicate potential innate immune factors influencing disease severity, but larger studies are needed to confirm these findings.

The immunopathogenesis of SARS-CoV-2 infection: Overview of lessons learned in the first 5 years

This review provides a broad overview of lessons learned in the five years since COVID-19 was identified. It is a bimodal disease, starting with an initially virus-driven phase, followed by resolution or ensuing inappropriate immune activation causing severe inflammation that is no longer strictly virus dependent. Humoral immunity is beneficial for preventing or attenuating the early stage, without benefit once the later stage begins. Neutralizing antibodies elicited by natural infection or vaccination are short-lived and highly vulnerable to viral sequence variation. By contrast, cellular immunity, particularly the CD8+ T cell arm, has a role in preventing or attenuating severe disease, is far less susceptible to viral variation, and is longer-lived than antibodies. Finally, an ill-defined phenomenon of prolonged symptoms after acute infection, termed "long COVID," is poorly understood but may involve various immunologic defects that are hyperactivating or immunosuppressive. Remaining issues include needing to better understand the immune dysregulation of severe disease to allow more tailored therapeutic interventions, developing antibody strategies that cope with the viral spike sequence variability, prolonging vaccine efficacy, and unraveling the mechanisms of long COVID to design therapeutic approaches.

C. Chen L. ABO blood group and COVID-19 severity: Associations with endothelial and adipocyte activation in critically ill patients

BACKGROUND

ABO blood group has been implicated both in susceptibility to, and severity of, SARS-CoV-2 infection. The aim of this study was to explore a potential association between ABO blood group and severity of COVID-19 infection in critically ill patients and the following biological mechanisms: inflammatory cytokines, endothelial injury, and adipokines.

METHODS

We conducted a retrospective study of 128 critically ill COVID-19 patients admitted to Vancouver General Hospital from March 2020-March 2021. Outcomes including 28-day mortality, need for mechanical ventilation and length of intensive care unit (ICU) stay were compared between patients with A & AB blood type vs. B & O blood type. Likewise, serum inflammatory markers, markers of endothelial activation, and adipokines were compared.

RESULTS

The association between ABO and severity of disease was confirmed. Patients with A&AB blood group had more frequent ventilation requirements compared to patients with blood group B&O (N(%): 35 (71%) vs 41 (52%), p = 0.041), higher total ICU mortality (14 (29%) vs 9 (11%), p = 0.018), longer median ICU stay (days, median [interquartile range]: 10 [6-19], vs 7 [3-14], p = 0.016) and longer median hospital stay (26 [14-36] vs. 17 [10-30] p = 0.034). No association was found between ABO blood group and serum inflammatory cytokines or their receptors [IL-6, IL-1b, IL-10, TNF, sIL-6R, sgp130] measured within the first 10 days of ICU stay. No association was found between ABO and plasma markers of endothelial injury [Thrombomodulin, ADAMTS13, sP-Selectin, Factor IX, Protein C, Protein S, vWF]. Among the plasma adipokines, there were no differences between lipocalin-2, PAI-1 or resistin. Notably, however, median adipsin was higher in patients with A&AB blood group compared to O&B (16.3 [4.2-38.5] x106 pg/mL vs. 9.61 [3.0-20.8] x 106 pg/mL, p = 0.048).

CONCLUSIONS

This retrospective single-center study confirms an association between A and AB blood type with more severe COVID-19. While an underlying mechanism was not identified, the finding of higher adipsin levels in patients with type A/AB blood warrants further investigation in larger prospective studies.

The Investigation of the Distribution of ABO/Rh Blood Group in Hospitalized COVID-19 Patients and Its Association With Disease Severity, Clinical Outcomes, Lab Tests, and Radiologic Findings

Background and Aims

it is important to identify patients at higher risk for severity and poor outcomes of COVID-19 infection, to have better disease management and pandemic control. In this study, we aimed to assess the distribution of ABO and Rh blood groups in hospitalized COVID-19 infected patients and demonstrate its association with severity and outcomes of the disease.

Methods

This is a cross-sectional study at Ziaeian Specialist Hospital, in Tehran, Iran. Of all confirmed COVID-19 infected patients who were admitted to this hospital, 273 patients were enrolled in this study and categorized based on their disease severity or clinical outcomes including intensive care unit (ICU) admission, need for mechanical ventilation and mortality. The distribution of ABO and Rh blood groups was assessed and compared between different groups, to investigate the association of blood group types with disease severity or outcomes. Also, the study population was categorized based on their blood group types to demonstrate the association of laboratory parameters, radiologic findings, and length of hospitalization with blood groups. Sex, age and underlying disease were adjusted in the final model by multivariate regression analysis.

Results

This study showed that Blood group A (35.9%) was the most prevalent among hospitalized COVID-19 patients followed by O (34.8%), B (21.6%), and AB (7.7%) (A > O > B > AB). ABO and Rh blood group was not associated with disease severity, need for mechanical ventilation, or ICU admission, while blood group B was associated with an increased risk of death in comparison with type O, in hospitalized COVID-19 patients (p = 0.02). The number of patients with severe levels of C-reactive protein (CRP) test results was lower in O blood group patients in comparison with non-O blood groups (p = 0.01).

Conclusion

No significant association was found between blood groups and other lab tests, radiologic findings, and length of hospitalization.

Tofacitinib Mitigates the Increased SARS-CoV-2 Infection Susceptibility Caused by an IBD Risk Variant in the PTPN2 Gene

BACKGROUND & AIMS

Coronavirus disease (COVID-19), caused by severe acquired respiratory syndrome-Coronavirus-2 (SARS-CoV-2), triggered a global pandemic with severe medical and socioeconomic consequences. Although fatality rates are higher among the elderly and those with underlying comorbidities, host factors that promote susceptibility to SARS-CoV-2 infection and severe disease are poorly understood. Although individuals with certain autoimmune/inflammatory disorders show increased susceptibility to viral infections, there is incomplete knowledge of SARS-CoV-2 susceptibility in these diseases. The aim of our study was to investigate whether the autoimmunity risk gene, PTPN2, which also confers elevated risk to develop inflammatory bowel disease, affects susceptibility to SARS-CoV-2 viral uptake.

METHODS

Using samples from PTPN2 genotyped patients with inflammatory bowel disease, PTPN2-deficient mice, and human intestinal and lung epithelial cell lines, we investigated how PTPN2 affects expression of the SARS-CoV-2 receptor angiotensin converting enzyme 2 (ACE2), and uptake of virus-like particles expressing the SARS-CoV2 spike protein and live SARS-CoV-2 virus.

RESULTS

We report that the autoimmune PTPN2 loss-of-function risk variant rs1893217 promotes expression of the SARS-CoV-2 receptor, ACE2, and increases cellular entry of SARS-CoV-2 spike protein and live virus. Elevated ACE2 expression and viral entry were mediated by increased Janus kinase-signal transducers and activators of transcription signaling and were reversed by the Janus kinase inhibitor, tofacitinib.

CONCLUSION

Collectively, our findings uncover a novel risk biomarker for increased expression of the SARS-CoV-2 receptor and viral entry, and identify a clinically approved therapeutic agent to mitigate this risk.

Lack of association of ABO and RhD blood groups with COVID-19 mortality: A 2-center cross-sectional study in Saudi Arabia

Several diseases, including both noninfectious diseases and bacterial and viral diseases, are associated with the ABO and RH blood group systems. Previous studies have shown a link between blood type and the probability of coronavirus disease 2019 (COVID-19) infection. In this study, we aimed to explore the correlation between deaths caused by COVID-19 and ABO and RhD blood types in Saudi Arabia. In this cross-sectional observational study, data from COVID-19 patients were collected from 2 major hospitals treating COVID-19 in Riyadh City, Saudi Arabia, between March 2020 and November 2021. The association between ABO and RhD blood types and COVID-19 outcomes was investigated. A total of 2302 real-time polymerase chain reaction-confirmed COVID-19 patients were enrolled in this study; a chi-square test was used to determine the statistical significance of the data. Of the 2302 enrolled patients, 1008 (43.8%) had blood type O, 677 (29.41%) had blood type A, 502 (21.8%) had blood type B, and 115 (5%) had blood type AB. Of the patients, 2143 (93.1%) were RhD-positive. The O-positive blood type had the highest mortality rate among COVID-19-infected patients, whereas the AB-negative type had the lowest. However, statistical analysis revealed no significant correlation between blood type (ABO or RhD) and COVID-19-based susceptibility or mortality. In conclusion, we found no association between ABO and RhD blood types and either susceptibility to or mortality due to COVID-19 in Saudi Arabia.

ABO and Rhesus blood groups and multiple health outcomes: an umbrella review of systematic reviews with meta-analyses of observational studies

BACKGROUND

Numerous studies have been conducted to investigate the relationship between ABO and Rhesus (Rh) blood groups and various health outcomes. However, a comprehensive evaluation of the robustness of these associations is still lacking.

METHODS

We searched PubMed, Web of Science, Embase, Scopus, Cochrane, and several regional databases from their inception until Feb 16, 2024, with the aim of identifying systematic reviews with meta-analyses of observational studies exploring associations between ABO and Rh blood groups and diverse health outcomes. For each association, we calculated the summary effect sizes, corresponding 95% confidence intervals, 95% prediction interval, heterogeneity, small-study effect, and evaluation of excess significance bias. The evidence was evaluated on a grading scale that ranged from convincing (Class I) to weak (Class IV). We assessed the certainty of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation criteria (GRADE). We also evaluated the methodological quality of included studies using the A Measurement Tool to Assess Systematic Reviews (AMSTAR). AMSTAR contains 11 items, which were scored as high (8-11), moderate (4-7), and low (0-3) quality. We have gotten the registration for protocol on the PROSPERO database (CRD42023409547).

RESULTS

The current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations. We re-calculated each association and found only one convincing evidence (Class I) for an association between blood group B and type 2 diabetes mellitus risk compared with the non-B blood group. It had a summary odds ratio of 1.28 (95% confidence interval: 1.17, 1.40), was supported by 6870 cases with small heterogeneity (I2 = 13%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger's test > 0.10, but the largest study effect was not more conservative than the summary effect size) or excess of significance (P < 0.10, but the value of observed less than expected). And the article was demonstrated with high methodological quality using AMSTAR (score = 9). According to AMSTAR, 18, 32, and 11 studies were categorized as high, moderate, and low quality, respectively. Nine statistically significant associations reached moderate quality based on GRADE.

CONCLUSIONS

Our findings suggest a potential relationship between ABO and Rh blood groups and adverse health outcomes. Particularly the association between blood group B and type 2 diabetes mellitus risk.

Investigating ABO Blood Groups and Secretor Status in Relation to SARS-CoV-2 Infection and COVID-19 Severity

The ABO blood groups, Lewis antigens, and secretor systems are important components of transfusion medicine. These interconnected systems have been also shown to be associated with differing susceptibility to bacterial and viral infections, likely as the result of selection over the course of evolution and the constant tug of war between humans and infectious microbes. This comprehensive narrative review aimed to explore the literature and to present the current state of knowledge on reported associations of the ABO, Lewis, and secretor blood groups with SARS-CoV-2 infection and COVID-19 severity. Our main finding was that the A blood group may be associated with increased susceptibility to SARS-CoV-2 infection, and possibly also with increased disease severity and overall mortality. The proposed pathophysiological pathways explaining this potential association include antibody-mediated mechanisms and increased thrombotic risk amongst blood group A individuals, in addition to altered inflammatory cytokine expression profiles. Preliminary evidence does not support the association between ABO blood groups and COVID-19 vaccine response, or the risk of developing long COVID. Even though the emergency state of the pandemic is over, further research is needed especially in this area since tens of millions of people worldwide suffer from lingering COVID-19 symptoms.

Lewis a-b- histo-blood group antigen phenotype is predictive of severe COVID-19 in the black South African population group

Several risk factors have been associated with SARS-CoV-2 infections and severity of COVID-19 disease it causes. This study investigated whether variations in histo-blood group antigen (HBGA) expression can predispose individuals to SARS-CoV-2 infections and severity of the disease. Nasopharyngeal swabs, randomly selected from SARS-CoV-2 positive and SARS-CoV-2 negative individuals, were tested for Lewis and H-type 1 HBGA phenotypes by ELISA using monoclonal antibodies specific to Lewis a, Lewis b and H type 1 antigens. The most common Lewis HBGA phenotype among all study participants was Lewis a-b+ (46%), followed by Lewis a-b- (24%), Lewis a+b- and Lewis a+b+ (15% each), while 55% of the study participants were H-type 1. Although SARS-CoV-2 negative individuals had a lower likelihood of having a Lewis a-b- phenotype compared to their SARS-CoV-2 positives counterparts (OR: 0.53, 95% C.I: 0.255-1.113), it did not reach statistical significance (P = 0.055). The frequency of Lewis a+b+, Lewis a+B-, Lewis a-b+, H type 1 positive and H type 1 negative were consistent between SARS-CoV-2 positive and SARS-CoV-2 negative individuals. When stratified according to severity of the disease, individuals with Lewis a+b- phenotype had a higher likelihood of developing mild COVID-19 symptoms (OR: 3.27, 95% CI; 0.9604-11.1), but was not statistically significant (P = 0.055), while Lewis a-b- phenotype was predictive of severe COVID-19 symptoms (OR: 4.3, 95% CI: 1.274-14.81), P = 0.016. In conclusion, individuals with Lewis a-b- phenotype were less likely to be infected by SARS-CoV-2, but when infected, they were at risk of severe COVID-19.

Association of ABO and Rhesus blood groups with severe outcomes from non-SARS-CoV-2 respiratory infection: A prospective observational cohort study in Bristol, UK 2020-2022

Despite significant global morbidity associated with respiratory infection, there is a paucity of data examining the association between severity of non-SARS-CoV-2 respiratory infection and blood group. We analysed a prospective cohort of adults hospitalised in Bristol, UK, from 1 August 2020 to 31 July 2022, including patients with acute respiratory infection (pneumonia [n = 1934] and non-pneumonic lower respiratory tract infection [NP-LRTI] [n = 1184]), a negative SARS-CoV-2 test and known blood group status. The likelihood of cardiovascular complication, survival and hospital admission length was assessed using regression models with group O and RhD-negative status as reference groups. Group A and RhD-positive were over-represented in both pneumonia and NP-LRTI compared to a first-time donor population (p < 0.05 in all); contrastingly, group O was under-represented. ABO group did not influence cardiovascular complication risk; however, RhD-positive patients with pneumonia had a reduced odds ratio (OR) for cardiovascular complications (OR = 0.77 [95% CI = 0.59-0.98]). Compared to group O, group A individuals with NP-LRTI were more likely to be discharged within 60 days (hazard ratio [HR] = 1.17 [95% CI = 1.03-1.33]), while group B with pneumonia was less likely (HR = 0.8 [95% CI = 0.66-0.96]). This analysis provides some evidence that blood group status may influence clinical outcome following respiratory infection, with group A having increased risk of hospitalisation and RhD-positive patients having reduced cardiovascular complications.

Changes in prevalence of anxiety and depression among COVID-19 patients during a two-year recovery period: A systematic review and meta-analysis

OBJECTIVE

To analyze the temporal trend of anxiety and depression prevalences up to 2 years of follow-up for COVID-19 patients during the recovery period and to compare regional differences.

METHODS

We performed a systematic review from PubMed, Embase, Web of Science, CNKI, Wanfang, and VIP using keywords such as "COVID-19", "anxiety", "depression", and "cohort study". Meta-analysis was performed to estimate the pooled prevalence of anxiety and depression at five follow-up time intervals. Subgroup analyses were conducted by different regions.

RESULTS

34 cohort studies were included in the meta-analyses. The pooled anxiety prevalence rates at 0-1 month, 1-3 months, 3-6 months, 6-12 months and 12-24 months were 18% (95% CI: 11% to 28%), 18% (95% CI: 12% to 28%), 22% (95% CI: 16% to 29%), 15% (95% CI: 11% to 21%), and 10% (95% CI: 0.05% to 20%), respectively, and the pooled depression prevalence rates were 22% (95%CI: 15% to 33%), 19% (95% CI: 13% to 29%), 21% (95% CI: 15% to 28%), 15% (95% CI: 11% to 20%), and 9% (95% CI: 0.4% to 21%) respectively. The prevalence of depression in Asian and non-Asian countries was statistically different at 0-1 month (χ2 = 15.248, P < 0.001) and 1-3 months (χ2 = 28.298, P < 0.001), and prevalence of anxiety was statistically different at 3-6 months (χ2 = 9.986, P = 0.002) and 6-12 months (χ2 = 7.378, P = 0.007).

CONCLUSION

The prevalence of anxiety and depression in COVID-19 patients generally tends to decrease after 2 years of recovery, but may temporarily increase at 3-6 months. There are regional differences in the changes in prevalence of anxiety and depression.

Familial Aggregation and ABO Blood Groups and COVID-19 Severity Among Hospitalized Patients

Background

Planning effective preventive and control measures requires understanding of the variability in the severity of infectious illnesses and factors determining susceptibility. The present study aimed to assess the association between familial susceptibility and ABO blood group with COVID-19 disease severity and adverse outcomes.

Methods

The present study was a retrospective investigation that was carried out at a tertiary care hospital with a bed capacity of 560 in the state of Kerala, India. A structured questionnaire was used to extract demographic and clinical characteristics from screened records. The study participants were stratified into 2 distinct groups based on the severity of their illness: mild to moderate and severe. Familial aggregation was operationally defined as the occurrence of COVID-19 diagnosis in any first-degree relative.

Results

A total of 362 hospitalized patients with confirmed COVID-19 infection were included in the analysis. Among them 62 (17.1%) were categorized as severe COVID-19 and 300 (82.9%) were categorized as mild to moderate COVID-19. Binary logistic regression analysis showed that the odds of sever COVID-19 disease was significantly higher among patients with familial aggregation (odds ratio, 2.47; 95% confidence interval, 2.12–2.85) and with non-O blood group (odds ratio, 2.21; 95% confidence interval, 2.01–2.56).

Conclusions

The findings of our study highlight the significance of familial aggregation and ABO blood group as crucial factors in determining the severity of COVID-19 disease. Comprehending the interrelationship between these variables and the genetic makeup of the host may hold significance in prognosticating the gravity of COVID-19 consequences.

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.

Association between ABO blood type and coronavirus disease 2019 severe outcomes across dominant variant strains

Objectives

Existing evidence suggests a link between ABO blood type and severe outcomes in coronavirus disease 2019 (COVID-19). We aimed to assess the relationship between blood type and severe outcomes across variant strains throughout the pandemic.

Methods

This was a multicenter retrospective observational cohort analysis from a large health system in southeastern Michigan using electronic medical records to evaluate emergency encounters, hospitalization, and severe outcomes in COVID-19 based on ABO blood type. Consecutive adult patients presenting to the emergency department with a primary diagnosis of COVID-19 (U07.1) from March 1, 2020 through December 31, 2022 were assessed. Patients who presented during three distinct time intervals that coincided with Alpha, Delta, and Omicron variant predominance were included in the analysis. Exclusions included no record of ABO blood type, positive PCR COVID-19 test within the preceding 28 days, and if transferred from out of the health system. Severe outcomes were inclusive of intensive care unit admission, mechanical ventilation, or death, which, as a composite, represented our primary outcome. Secondary outcomes were hospital admission and length of stay. A logistic regression model was employed to test the association between ABO blood type and severe outcome, adjusting for age, sex, race, vaccination status, Elixhauser comorbidity indices, and the dominant variant time period in which the encounter occurred.

Results

Of the 33,796 COVID-19 encounters, 9416 met inclusion criteria; 4071 (43.2%) were type O, 3417 (36.3%) were type A, 459 (4.9%) were type AB, and 1469 (15.6%) were type B blood. Note that 66.4% of the cohort was female (p = 0.18). The proportion of composite severe disease among the four blood types was similar and ranged between 8.6% and 8.9% (p = 0.98). Note that 53.0% of type A blood patients required hospital admission, compared to 51.9%, 50.4%, and 48.1% of type AB, B, and O blood, respectively (p < 0.001). Compared to patients with O blood type (43.2%), non-O blood type (58.8%; composite of A, AB, and B) exhibited no statistically significant difference in the proportion of composite severe disease (8.8% vs. 8.7%; p = 0.81) Multivariable regression analyses exhibited no significant difference regarding the presence of severe outcomes among the four blood types or O versus non-O blood types during T1, T2, and T3.

Conclusions

ABO blood type was not associated with COVID-19 severe outcomes across the Delta, Alpha, and Omicron dominant COVID waves across a large health system in southeastern Michigan. Further research is needed to better understand if ABO blood type is a risk factor for severe disease among evolving COVID-19 variants and other viral upper respiratory infections.

Best Evidence Topic report: does blood group type O decrease the risk of severe COVID-19 infection?

A short-cut systematic review was conducted using a described protocol. The three-part question addressed was: In patients with COVID-19 infection, does blood group type O versus non-O blood groups lead to a lower risk of severe COVID-19 infection? MEDLINE, Embase, and Cochrane databases were searched for relevant evidence. Altogether, 238 papers were found using the search strategy developed. Seventeen provided the best evidence to answer the three-part question. The data on first author name, publication year, country of origin, study type, study sample size, participant's gender, reported effect sizes, main findings and limitations were extracted from the relevant studies and listed in a table. Finally, 4 out of 17 studies revealed that having blood group type O may be associated with a lower risk of severe COVID-19 among patients with COVID-19 infection and the 13 remaining studies reported no significant relationship between having O blood group and risk of COVID-19 severity among the infected individuals. Of three systematic reviews and meta-analyses identified, none detected a protective effect of blood group type O. The clinical bottom line is that the best available evidence does not support the notion that blood group type O is protective against serious outcomes in COVID-19.

Association of ABO blood group, Rh phenotype and MN blood group with susceptibility to COVID-19

BACKGROUND

Previous studies have reported that the susceptibility to coronavirus disease 2019 (COVID-19) is related to ABO blood group, but the relationship with Rh phenotype and MN blood group is unknown. China had adopted a strict control policy on COVID-19 until December 5, 2022, when local communities were liberalized. Therefore, we aimed to explore the correlation between ABO blood group, Rh phenotype, MN blood group and susceptibility to COVID-19 based on the time sequence of infection during the pandemic.

METHODS

A total of 870 patients who were routinely hospitalized in Ningbo Medical Center Lihuili Hospital from March 1, 2023 to March 31, 2023 were randomly selected to enroll in this study. Patients were divided into susceptible group and non-susceptible group, according to the time of their previous infection. The demographics and clinical information of the enrolled participants were collected from electronic medical records. The association of ABO blood group, Rh phenotype and MN blood group with susceptibility to COVID-19 was analyzed.

RESULTS

A total of 650 cases (74.7%) had been infected with COVID-19, with 157 cases (18.0%) in the second week and 252 cases (29.0%) in the third week, reaching the peak of infection. Compared with the non-susceptible group, the susceptible group had no statistically significant differences in ABO blood group and Rh phenotype, but the proportion of N+ was higher (75.6% vs 68.9%, P = 0.030) and the proportion of MM was lower (24.4% vs 31.1%, P = 0.030). Consistent with this, ABO blood group and Rh phenotype were not significantly associated with susceptibility to COVID-19 (P>0.05), while N+ and MM were associated with susceptibility to COVID-19 (OR: 1.432, 95% confidence interval [CI]: 1.049, 1.954, P = 0.024; OR: 0.698, 95% CI: 0.512, 0.953, P = 0.024, respectively), after adjusting for age, sex, BMI, basic disease, and vaccination status in multivariate logistic regression analysis.

CONCLUSION

Our study showed that ABO blood group and Rh phenotype may not be related to the susceptibility to COVID-19, but MN blood group may be associated with the susceptibility to COVID-19.

Allele-specific long-range sequencing as a method for ABO haplotyping in clinical blood group diagnosis and immunohematology research

BACKGROUND

Safe transfusion therapy requires accurate testing of blood donors and recipients to determine their ABO blood group compatibility. Genotyping does not always clarify serological blood typing discrepancies and conventional PCR methods are not suitable to identify ABO haplotypes. Therefore, an allele-specific long-range sequencing-based typing method was established.

METHODS

Study samples (n = 100) and six patient samples were ABO phenotyped and screened for specific single nucleotide polymorphisms (SNP) in the ABO gene. Based on identified heterozygous SNPs in intron 1 (12897G>A), 2 (437C>T) or 4 (102C>A, 1511G>T) both ABO alleles were investigated separately using a high-fidelity long-range PCR system and Sanger sequencing. The alleles were correlated to the ABO phenotypes determined.

RESULTS

Direct sequencing of allelic PCR products up to 6743 bases has been successful in discriminating common combinations of the ABO*A1.01, ABO*A2.01, ABO*B.01, ABO*O.01.01, ABO*O.01.02 and ABO*O.02.01 alleles. 10 out of 64 haplotypes were found to be not previously described. The uncommon ABO*AW.31.01 and the unusual O alleles ABO*O.05 and ABO*O.02.03 alleles were detected in patient samples, resolving the initial inconclusive serologic ABO typing results.

CONCLUSION

This method is an effective tool for analyzing ABO haplotypes. Applicable for ABO molecular diagnostics and immunohematology research it may help to improve pre-transfusion blood type testing.

Association between ABO blood group/genotype and COVID-19 in a Japanese population

An association between coronavirus disease 2019 (COVID-19) and the ABO blood group has been reported. However, such an association has not been studied in the Japanese population on a large scale. Little is known about the association between COVID-19 and ABO genotype. This study investigated the association between COVID-19 and ABO blood group/genotype in a large Japanese population. All Japanese patients diagnosed with COVID-19 were recruited through the Japan COVID-19 Task Force between February 2020 and October 2021. We conducted a retrospective cohort study involving 1790 Japanese COVID-19 patients whose DNA was used for a genome-wide association study. We compared the ABO blood group/genotype in a healthy population (n = 611, control) and COVID-19 patients and then analyzed their associations and clinical outcomes. Blood group A was significantly more prevalent (41.6% vs. 36.8%; P = 0.038), and group O was significantly less prevalent (26.2% vs. 30.8%; P = 0.028) in the COVID-19 group than in the control group. Moreover, genotype OO was significantly less common in the COVID-19 group. Furthermore, blood group AB was identified as an independent risk factor for most severe diseases compared with blood group O [aOR (95% CI) = 1.84 (1.00-3.37)]. In ABO genotype analysis, only genotype AB was an independent risk factor for most severe diseases compared with genotype OO. Blood group O is protective, whereas group A is associated with the risk of infection. Moreover, blood group AB is associated with the risk of the "most" severe disease.

Correlation between ABO blood type, susceptibility to SARS-CoV-2 infection and COVID-19 disease severity: A systematic review

OBJECTIVES

To verify the association between the ABO blood type and the risk of SARS-CoV-2 infection and COVID-19 disease severity.

METHODS

This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), using the 2020 PRISMA Checklist and flow diagram, and articles selected for review were analyzed using the Newcastle-Ottawa Quality Rating Scale. The research question was: "Would the ABO blood group influence the risk of infection and clinical course of patients infected with SARS-CoV-2?", The following databases were used: Embase, PubMed, Virtual Health Library (VHL), Web of Science, ScienceDirect and Scopus. The protocol for this review was registered in the Prospective Register of Systematic Reviews (PROSPERO), number CRD42021245945.

RESULTS

We found 798 articles across PubMed, Embase, Scopus, Web of Science, Science Direct and Virtual Health Library and 54 articles were included in the final analysis. Among 30 studies evaluating the risk of COVID-19 infection, 21 found significant correlations with ABO blood groups, 14 of them revealing an increased risk in blood group A and 15 studies showing a decreased risk in blood group O. Most studies found no significant correlation with disease severity or mortality.

CONCLUSION

The qualitative assessment of available information suggests that blood group A may be a risk factor for COVID-19 infection and that blood group O may have a protective effect. We were unable to determine a clear association between the ABO blood group and mortality. These conclusions are based on highly heterogenous evidence.

ABO blood group and rhesus factor association with inpatient COVID-19 mortality and severity: a two-year retrospective review

Background

Early reports have indicated a relationship between ABO and rhesus blood group types and infection with SARS-CoV-2. We aim to examine blood group type associations with COVID-19 mortality and disease severity.

Methods

This is a retrospective chart review of patients ages 18 years or older admitted to the hospital with COVID-19 between January 2020 and December 2021. The primary outcome was COVID-19 mortality with respect to ABO blood group type. The secondary outcomes were 1. Severity of COVID-19 with respect to ABO blood group type, and 2. Rhesus factor association with COVID-19 mortality and disease severity. Disease severity was defined by degree of supplemental oxygen requirements (ambient air, low-flow, high-flow, non-invasive mechanical ventilation, and invasive mechanical ventilation).

Results

The blood type was collected on 596 patients with more than half (54%, N=322) being O+. The ABO blood type alone was not statistically associated with mortality (P=0.405), while the RH blood type was statistically associated with mortality (P<0.001). There was statistically significant association between combined ABO and RH blood type and mortality (P=0.014). Out of the mortality group, the O+ group had the highest mortality (52.3%), followed by A+ (22.8%). The combined ABO and RH blood type was statistically significantly associated with degree of supplemental oxygen requirements (P=0.005). The Kaplan-Meier curve demonstrated that Rh- patients had increased mortality.

Conclusion

ABO blood type is not associated with COVID-19 severity and mortality. Rhesus factor status is associated with COVID-19 severity and mortality. Rhesus negative patients were associated with increased mortality risk.

ABO Blood Type and Metabolic Markers in COVID-19 Susceptibility and Severity: A Cross-Sectional Study

Background and Aims: To evaluate the effect of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus on the function and metabolic changes, as well as the relationship of the virus with blood groups. Methods and Results: This cross-sectional study included a matched sample of adult individuals with coronavirus disease 2019 (COVID-19) (n = 114) or without (controls; n = 236). Blood samples were collected and processed for triglycerides (TGs), total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and blood typing analysis. The results showed that subjects with COVID-19 had higher TG and lower HDL-C levels compared with the control group. As for blood typing, the risk of COVID-19 was higher in subjects with blood group A than in those with blood group B and in those with other blood groups. In addition, an association of COVID-19 with blood type and Rh A- was observed. When related to the severity of COVID-19 symptoms, blood type A was more protective against moderate/severe symptoms compared with blood type O. In addition, individuals with blood type O were 2.90 times more likely to have symptoms moderate/severe symptoms of COVID-19 than those with other blood groups and individuals with type A blood were less likely to have severe/moderate symptoms of COVID-19 compared with individuals without type A blood. Conclusion: The results suggest that blood type may play a role in susceptibility to SARS-CoV-2 infection and add evidence that infection with the novel coronavirus may be associated with changes in lipid metabolism.

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.

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.

Effectiveness of COVID-19 Convalescent Plasma (CCP) During the Pandemic Era: A Literature Review

Worldwide pandemic with coronavirus disease-2019 (COVID-19) was caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). As November 2, 2022, World Health Organization (WHO) received 628,035,553 reported incidents on COVID-19, with 6,572,800 mortalities and, with a total 12,850,970,971 vaccine doses have been delivered as of October 31, 2022. The infection can cause mild or self-limiting symptoms of pulmonary and severe infections or death may be caused by SARS-CoV-2 infection. Simultaneously, antivirals, corticosteroids, immunological treatments, antibiotics, and anticoagulants have been proposed as potential medicines to cure COVID-19 affected patients. Among these initial treatments, COVID-19 convalescent plasma (CCP), which was retrieved from COVID-19 recovered patients to be used as passive immune therapy, in which antibodies from cured patients were given to infected patients to prevent illness. Such treatment has yielded the best results in earlier with preventative or early stages of illness. Convalescent plasma (CP) is the first treatment available when infectious disease initially appears, although few randomized controlled trials (RCTs) were conducted to evaluate its effectiveness. The historical record suggests with potential benefit for other respiratory infections, as coronaviruses like Severe Acute Respiratory Syndrome-CoV-I (SARS-CoV-I) and Middle Eastern Respiratory Syndrome (MERS), though the analysis of such research is constrained by some non-randomized experiments (NREs). Rigorous studies on CP are made more demanding by the following with the immediacy of the epidemics, CP use may restrict the ability to utilize it for clinical testing, non-homogenous nature of product, highly decentralized manufacturing process; constraints with capacity to measure biologic function, ultimate availability of substitute therapies, as antivirals, purified immune globulins, or monoclonal antibodies. Though, it is still not clear how effectively CCP works among hospitalized COVID-19 patients. The current review tries to focus on its efficiency and usage in clinical scenarios and identifying existing benefits of implementation during pandemic or how it may assist with future pandemic preventions.

Blood-Type-A is a COVID-19 infection and hospitalization risk in a Turkish cohort

We have shown in an ethnically homogenous Turkey cohort with more than six thousand cases and 25 thousand controls that ABO blood types that contain anti-A antibody (O and B) are protective against COVID-19 infection and hospitalization, whereas those without the anti-A antibody (A and AB) are risks. The A + AB frequency increases from 54.7 % in uninfected controls to 57.6 % in COVID-19 outpatients, and to 62.5 % in COVID-19 inpatients. The odds-ratio (OR) for lacking of anti-A antibody risk for infection is 1.16 (95 % confidence interval (CI) 1.1-1.22, and Fisher test p-value 1.8 × 10^-7). The OR for hospitalization is 1.23 (95 %CI 1.06-1.42, Fisher test p-value 0.005). A linear regression treating controls, outpatients, inpatients as three numerical levels over anti-A antibody leads to a p-value of 5.9 × 10^-9. All these associations remain to be statistically significant after conditioning over age, even though age itself is a risk for both infection and hospitalization. We also attempted to correct the potential effect from vaccination, even though vaccination information is not available, by using the date of the data collection as a surrogate to vaccination status. Although no significant association between infection/hospitalization with Rhesus blood system was found, forest plots are used to illustrate possible trends.

Thrombocytopaenia and COVID-19 infection during pregnancy increases the risk of preeclampsia: a multicentre study

RESEARCH QUESTION

Is a low platelet count related to an increased risk of severe disease in pregnant women with active severe acute respiratory syndrome coronavirus 2 infection?

DESIGN

A cross-sectional multicentre study in pregnant women with COVID-19 confirmed by polymerase chain reaction, antigen test, antibody test, or all.

RESULTS

A total of 153 pregnant women with COVID-19 were included in the study, of whom 12.4% had thrombocytopaenia. Pregnant women with thrombocytopaenia were on average 3.1 years older (95% CI 0.18 to 6.38) than women without thrombocytopaenia. Pregnant smokers had a higher risk of thrombocytopaenia than non-smokers (OR 6.55, CI 95% 1.29 to 33.13). B Rh negative (B Rh-) pregnant women had a much higher risk of thrombocytopaenia than pregnant women with other blood groups (OR 16.83, CI 95% 1.42 to 199.8). Pregnant women with thrombocytopaenia had a much higher risk of suffering from preeclampsia (OR 16.2, CI 95% 1.35 to 193.4).

CONCLUSIONS

COVID-19 infection is not a risk factor for a low platelet count in pregnant women, although the risk is increased by smoking and in women with blood group B Rh-. In case of pregnancy with thrombocytopaenia, COVID-19 infection leads to an increased risk of preeclampsia.

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.

Effects of ABO blood groups and RH-factor on COVID-19 transmission, course and outcome: A review

ABO and Rh blood grouping systems are two of the non-modifiable risk factors that play an important role in the susceptibility, severity and outcomes of COVID-19 infection. This review explores these associations all over the world, in an attempt to conclude a clear idea for future reference in clinical practice. In the present review, a link has been drawn between blood groups and COVID-19 transmission, course and prognosis, as literature suggests that blood group O plays a protective role against the infection, while blood group A exhibits a higher risk of exacerbation. In contrast with Rh negative individuals, Rh positive individuals are prone to more severe infection and complications, despite the fact that the underlying mechanisms of this association remain understudied. Nevertheless, the connection remains subject to controversy; since some studies report doubts about it. Thus, this association requires further investigation.

The immunogenetics of COVID-19

The worldwide coronavirus disease 2019 pandemic was sparked by the severe acute respiratory syndrome caused by coronavirus 2 (SARS-CoV-2) that first surfaced in December 2019 (COVID-19). The effects of COVID-19 differ substantially not just between patients individually but also between populations with different ancestries. In humans, the human leukocyte antigen (HLA) system coordinates immune regulation. Since HLA molecules are a major component of antigen-presenting pathway, they play an important role in determining susceptibility to infectious disease. It is likely that differential susceptibility to SARS-CoV-2 infection and/or disease course in COVID-19 in different individuals could be influenced by the variations in the HLA genes which are associated with various immune responses to SARS-CoV-2. A growing number of studies have identified a connection between HLA variation and diverse COVID-19 outcomes. Here, we review research investigating the impact of HLA on individual responses to SARS-CoV-2 infection and/or progression, also discussing the significance of MHC-related immunological patterns and its use in vaccine design.

Relationships of ABO and Rhesus blood groups with type 2 diabetes mellitus: a systematic review and meta-analysis

OBJECTIVES

The susceptibility to type 2 diabetes mellitus (T2DM) has been linked to blood type. We aimed to characterize the relationships of the ABO and Rhesus blood groups with T2DM.

METHODS

Literature searches were performed using the Medline, PubMed, Scopus, Cochrane, EMBASE, and Google Scholar databases to identify studies published up to 31 March 2022. The PRISMA guidelines were used for reporting. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were obtained using fixed-effects models.

RESULTS

Twenty-six studies of 6870 patients with T2DM and 11,879 controls were identified. Compared with the other ABO groups, people with blood type B were at higher risk of T2DM (OR: 1.30, 95% CI: 1.20-1.41), while group O was associated with a lower risk (OR: 0.92, 95% CI: 0.86-0.98). There were no significant associations of T2DM with blood types A or AB, or Rh factor.

CONCLUSION

Individuals with blood type B are at higher risk of developing T2DM. Therefore, they should be screened for T2DM on a frequent basis and be made aware of the importance of maintaining a balanced diet and regular exercise for the prevention of obesity and T2DM.

PROSPERO REGISTRATION NUMBER

CRD42022353945.

Blood types (ABO/Rhesus) and SARS-CoV-2 infection: a retrospective, cross-sectional study in 2828 healthcare workers

Background: The authors aimed to investigate the relationship between ABO/Rhesus blood types and the risk of SARS-CoV-2 infection and hospitalization in healthcare workers (HCWs). Materials & methods: This study compared HCWs with (n = 510) and without (n = 2318) SARS-CoV-2 infection. Risk factors for SARS-CoV-2 infection and hospitalization in HCWs were shown as odds ratios with 95% CI. Results: Blood group O was found to be protective by 20% from the risk of developing SARS-CoV-2 infection in HCWs (29.2 vs 33.8%; odds ratio: 0.808; 95% CI: 0.655–0.996; p = 0.045). The prevalence of group O was lower in hospitalized patients than in outpatients (25 vs 29.5%; p = 0.614). Conclusion: These findings suggest that blood groups are associated with the development of SARS-CoV-2 infection.

In this study, the relationship between ABO blood groups and the development of SARS-CoV-2 infection was investigated in healthcare workers (HCWs) working in a tertiary hospital. A total of 2828 HCWs were included in the study. Of those, 510 (18%) had SARS-CoV-2 infection. The prevalence of blood group O was 33% (n = 933). The prevalence of group O was lower in hospitalized patients than in outpatients (25 vs 29.5%; p = 0.614). Further analysis revealed that blood group O was associated with a decreased risk of developing SARS-CoV-2 infection in HCWs by up to 20%.

In the study of Copur et al., #bloodgroupO was found to be protective by 20% from the risk of developing #SARS-CoV-2 #infection in #healthcareworkers.

Sequelae of COVID-19 among previously hospitalized patients up to 1 year after discharge: a systematic review and meta-analysis

OBJECTIVE

Although complications and clinical symptoms of COVID-19 have been elucidated, the prevalence of long-term sequelae of COVID-19 is less clear in previously hospitalized COVID-19 patients. This review and meta-analysis present the occurrence of different symptoms up to 1 year of follow-up for previously hospitalized patients.

METHODS

We performed a systematic review from PubMed and Web of Science using keywords such as "COVID-19", "SARS-CoV-2", "sequelae", "long-term effect" and included studies with at least 3-month of follow-up. Meta-analyses using random-effects models were performed to estimate the pooled prevalence for different sequelae. Subgroup analyses were conducted by different follow-up time, regions, age and ICU admission.

RESULTS

72 articles were included in the meta-analyses after screening 11,620 articles, identifying a total of 167 sequelae related to COVID-19 from 88,769 patients. Commonly reported sequelae included fatigue (27.5%, 95% CI 22.4-33.3%, range 1.5-84.9%), somnipathy (20.1%, 95% CI 14.7-26.9%, range 1.2-64.8%), anxiety (18.0%, 95% CI 13.8-23.1%, range 0.6-47.8%), dyspnea (15.5%, 95% CI 11.3-20.9%, range 0.8-58.4%), PTSD (14.6%, 95% CI 11.3-18.7%, range 1.2-32.0%), hypomnesia (13.4%, 95% CI 8.4-20.7%, range 0.6-53.8%), arthralgia (12.9%, 95% CI 8.4-19.2%, range 0.0-47.8%), depression (12.7%, 95% CI 9.3-17.2%, range 0.6-37.5%), alopecia (11.2%, 95% CI 6.9-17.6%, range 0.0-47.0%) over 3-13.2 months of follow-up. The prevalence of most symptoms reduced after > 9 months of follow-up, but fatigue and somnipathy persisted in 26.2% and 15.1%, respectively, of the patients over a year. COVID-19 patients from Asia reported a lower prevalence than those from other regions.

CONCLUSIONS

This review identified a wide spectrum of COVID-19 sequelae in previously hospitalized COVID-19 patients, with some symptoms persisting up to 1 year. Management and rehabilitation strategies targeting these symptoms may improve quality of life of recovered patients.

Association between ABO blood types and the prognosis and mortality rates in patients with severe COVID-19 admitted in the intensive care unit of a tertiary-level hospital in Turkey

OBJECTIVES

There is limited number of data showing possible correlation between ABO blood types and prognosis and mortality of COVID-19 patients. It was aimed to investigate whether ABO blood group type affects the prognosis and mortality rates in patients with severe COVID-19 hospitalized in the ICU (intensive care unit) of a tertiary-level hospital in Turkey.

METHODS

The data of 273 patients with diagnosis of severe COVID-19 who were admitted to ICU from April 2020 through June 2021 and in an age range between 25-93 years were evaluated in this retrospective study.

RESULTS

Blood group distribution was 47.3, 13.2, 10.6 and 28.9% for groups A, B, AB, and O, respectively. As a respiratory status at admission to ICU, the ratio of intubation patients with blood type O was significantly higher than of other groups while most of patients in group A achieved spontaneous respiration without any mechanical ventilator (p = .0168). The mean neutrophil ratio, NLR, concentrations of procalcitonin, lactate, urea and ferritin significantly increased in the serum of patients with type O (p < .01 for all except p = .016 for the ferritin). The weaning duration was longest among patients with blood group O while the hospitalization duration was longest among patients with group AB; however, there was not significant difference (p > .05). The highest mortality rate was calculated in group AB as 68.97% and lowest was 47.2% in group B without any statistical difference (p > .05).

CONCLUSION

ABO blood types carry different association risk factors for the prognosis of severe COVID-19 patients hospitalized in ICU. Specifically, blood group O was correlated with an increased risk of deterioration of respiratory status including intubation and elevation of laboratory findings whereas it did not affect the risk of increased mortality.

Visualizing novel connections and genetic similarities across diseases using a network-medicine based approach

Understanding the genetic relationships between human disorders could lead to better treatment and prevention strategies, especially for individuals with multiple comorbidities. A common resource for studying genetic-disease relationships is the GWAS Catalog, a large and well curated repository of SNP-trait associations from various studies and populations. Some of these populations are contained within mega-biobanks such as the Million Veteran Program (MVP), which has enabled the genetic classification of several diseases in a large well-characterized and heterogeneous population. Here we aim to provide a network of the genetic relationships among diseases and to demonstrate the utility of quantifying the extent to which a given resource such as MVP has contributed to the discovery of such relations. We use a network-based approach to evaluate shared variants among thousands of traits in the GWAS Catalog repository. Our results indicate many more novel disease relationships that did not exist in early studies and demonstrate that the network can reveal clusters of diseases mechanistically related. Finally, we show novel disease connections that emerge when MVP data is included, highlighting methodology that can be used to indicate the contributions of a given biobank.

Lower Levels of ABO Anti-A and Anti-B of IgM, IgG and IgA Isotypes in the Serum but Not the Saliva of COVID-19 Convalescents

Individuals with ABO type O, naturally possessing anti-A and anti-B antibodies in their serum, are underrepresented among patients infected with SARS-CoV-2 compared with healthy controls. The ABO antibodies might play a role in the viral transmission. Therefore, we aimed to quantify anti-A/anti-B, including their subclasses IgM, IgG and IgA, in the serum and saliva of Caucasians (n = 187) after mild COVID-19 to compare them with individuals who had never been infected with SARS-CoV-2. Two samples were collected within two months after the diagnosis (median days: 44) and two months later. ABO antibodies were determined by flow cytometry. Additionally, total IgA in saliva and antibodies specific to SARS-CoV-2 were tested by ELISA. COVID-19 convalescents had significantly lower levels of anti-A/anti-B IgM, IgG and IgA in their serum than control subjects (p < 0.001). Interestingly, no significant differences were observed in saliva. ABO antibody levels remained stable over the period considered. No relation of ABO to the level of SARS-CoV-2-specific antibodies was observed. Total IgA was lower in convalescents than in controls (p = 0.038). Whereas ABO antibodies in the saliva may not contribute to the pathogenesis of COVID-19, individual pre-existing high serum concentrations of anti-A/anti-B may have a protective effect against SARS-CoV-2 infection.

Association between Blood Group and COVID-19

Context:

COVID-19 is an emerging infectious disease and blood group has an influence on the susceptibility of infectious diseases including COVID-19.

Aim:

The present study was conducted with the aim to observe the association of ABO blood groups with COVID-19.

Setting and Design:

A nonexperimental hospital-based case–control research design was adopted to conduct the study with 200 COVID-19 patients who met the inclusion criteria.

Subjects and Methods:

Informed consent was obtained from the participants after explained the purpose of the study. Data were collected by interview method using a structured questionnaire and medical record was also utilized to collect the data. The collected data were prepared for analysis using Microsoft Excel.

Statistical Analysis Used:

Both descriptive and inferential statistical methods were used to analyze the data using the software SPSS 16 version.

Results:

The results of the study revealed that out of 200 participants, 83 (42.5%) belonged to A+, 68 (33%) belonged to B+, 7 (14%) belonged to O+, 18 (9%) belonged to AB +, and 4 (%) belonged to A-blood group.

Conclusion:

The findings of the current study concluded that the prevalence rate of COVID-19 was higher among non-O blood group than in the O blood group and the blood group is associated with the severity of illness. Despite further studies on the individuals with confirmed exposure to COVID-19 infection should be conducted with large samples to generalize the findings.

Systematic review and meta-analysis of the effect of ABO blood group on the risk of SARS-CoV-2 infection

We have been experiencing a global pandemic with baleful consequences for mankind, since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was first identified in Wuhan of China, in December 2019. So far, several potential risk factors for SARS-CoV-2 infection have been identified. Among them, the role of ABO blood group polymorphisms has been studied with results that are still unclear. The aim of this study was to collect and meta-analyze available studies on the relationship between SARS-CoV-2 infection and different blood groups, as well as Rhesus state. We performed a systematic search on PubMed/MEDLINE and Scopus databases for published articles and preprints. Twenty-two studies, after the removal of duplicates, met the inclusion criteria for meta-analysis with ten of them also including information on Rhesus factor. The odds ratios (OR) and 95% confidence intervals (CI) were calculated for the extracted data. Random-effects models were used to obtain the overall pooled ORs. Publication bias and sensitivity analysis were also performed. Our results indicate that blood groups A, B and AB have a higher risk for COVID-19 infection compared to blood group O, which appears to have a protective effect: (i) A group vs O (OR = 1.29, 95% Confidence Interval: 1.15 to 1.44), (ii) B vs O (OR = 1.15, 95% CI 1.06 to 1.25), and (iii) AB vs. O (OR = 1.32, 95% CI 1.10 to 1.57). An association between Rhesus state and COVID-19 infection could not be established (Rh+ vs Rh- OR = 0.97, 95% CI 0.83 to 1.13).

Association of IgE elevation with blood group in COVID-19 patients

Aim : All parameters that are thought to be efficient in getting sick and follow-up of the disease should be investigated because of COVID-19 disease has serious consequences. The aim of this study was to investigate whether there is a relationship between the AB0 blood group with Rh factor systems and the frequency of catching COVID-19 infection and between IgE elevation according to blood groups and COVID-19 positivity. Material and Method: Blood groups and IgE levels of the control group (2690 patients) were compared retrospectively with 7300 patients who were admitted to our hospital between March 10, 2020, and March 31, 2021, and confirmed as COVID-19 positive with viral ribonucleic acid reverse transcriptase-polymerase chain reaction (RT-PCR). Results: It was found that among the blood groups, the highest COVID-19 positivity belonged to the A blood group (46.17%) and the lowest belonged to the AB blood group (9.04%). The increase in IgE elevation was found statistically significant in COVID-19 positive patients (P

Fucosyltransferase 2: A Genetic Risk Factor for Intestinal Diseases

The fucosyltransferase 2 gene (FUT2) mediates the synthesis of histoblood group antigens (HBGA) that occur in vivo from multiple organs, particularly on the surface of intestinal epithelial cells and body fluids. To date, many studies have demonstrated that the interaction of HBGA with the host microbiota is the cause of pathogenesis of intestinal diseases, making FUT2 non-secretor a risk factor for inflammatory bowel disease (IBD) due to the lack of HBGA. As HBGA also acts as an attachment site for norovirus (NoV) and rotavirus (RV), the non-secretor becomes a protective factor for both viral infections. In addition, the interaction of norovirus and rotavirus with symbiotic bacteria has been found to play an important role in regulating enteroviral infection in IBD. Given the current incomplete understanding of the complex phenomenon and the underlying pathogenesis of intestinal diseases such as IBD, it has recently been hypothesized that the FUT2 gene regulates intestinal bacteria through attachment sites, may help to unravel the role of FUT2 and intestinal flora in the mechanism of intestinal diseases in the future, and provide new ideas for the prevention and treatment of intestinal diseases through more in-depth studies.

Correlation of SARS-CoV-2 infection severity with ABO blood groups and RhD antigen: a case-control study

OBJECTIVE

The role of ABO types and RhD antigen in coronavirus disease 2019 (COVID-19) severity has been investigated in several recent studies. Thus, the objective of this study was to identify the relationship of ABO and RhD types with symptomatic COVID-19 disease and determine the groups associated with an increased risk of hospitalization.

METHODS

This observational case-control study was performed in 530 Iraqi-Kurdish patients with COVID-19. Among them, 184 were severe cases that required hospitalization, while 346 were mild to moderate cases that were treated at home. ABO and RhD antigen groups were compared between cases and 1698 control records from 1 year before the pandemic. The diagnosis of COVID-19 was based on real-time polymerase chain reaction tests and high-resolution chest computed tomography scans with the typical clinical presentation.

RESULTS

There were no significant differences in ABO and RhD antigen distributions between the COVID-19 cases and non-COVID controls. No ABO group was associated with the risk of hospitalization as a marker of the severity of infection.

CONCLUSIONS

There was no significant association between symptomatic COVID-19 disease and any ABO group or RhD antigen type. No impact of ABO groups on hospitalization was documented.

A Comprehensive Comparison of Clinical Presentation and Outcomes of Kidney Transplant Recipients with COVID-19 during Wave 1 versus Wave 2 at a Tertiary Care Center, India

Data comparing the clinical spectrum of COVID-19 in kidney transplant recipients (KTRs) during the first and second waves of the pandemic in India is limited. Our single-center retrospective study compared the clinical profile, mortality, and associated risk factors in KTRs with COVID-19 during the 1st wave (1^st February 2020 to 31^st January 2021) and the second wave (1^st March-31^st August 2021). 156 KTRs with PCR confirmed SARS-CoV-2 infection treated at a tertiary care hospital in New Delhi during the 1st and the second waves were analyzed. The demographics and baseline transplant characteristics of the patients diagnosed during both waves were comparable. Patients in the second wave reported less frequent hospitalization, though the intensive care unit (ICU) and ventilator requirements were similar. Strategies to modify immunosuppressants such as discontinuation of antinucleoside drugs with or without change in calcineurin inhibitors and the use of steroids were similar during both waves. Overall patient mortality was 27.5%. The demographics and baseline characteristics of survivors and nonsurvivors were comparable. A higher percentage of nonsurvivors presented with breathing difficulty, low SpO₂, and altered sensorium. Both wave risk factors for mortality included older age, severe disease, ICU/ventilator requirements, acute kidney injury (AKI) needing dialysis, Chest Computerized Tomographic (CT) scan abnormalities, and higher levels of inflammatory markers particularly D-dimer and interleukin-6 levels. Conclusions. KTRs in both COVID-19 waves had similar demographics and baseline characteristics, while fewer patients during the second wave required hospitalization. The D-dimer and IL-6 levels are directly correlated with mortality.

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.

The Role of ABO Blood Type in Patients with SARS-CoV-2 Infection: A Systematic Review

The SARS-CoV-2 infection has caused over 422 million contagions and 5.8 million deaths resulting in a global health crisis. Several studies have investigated the risk factors predisposing to the infection and reported that the host susceptibility can be linked to the ABO blood group, but the current evidence is controversial. We systematically searched for articles in EMBASE, PubMed, and Cochrane library published up to 7 May 2021 to explore the association of the ABO blood group with the susceptibility to SARS-CoV-2 infection. All studies in people undergoing SARS-CoV-2 test controls were included. Odds ratios were obtained in each study and then synthesised by using meta-analysis. Overall, 22 articles were selected and more than 1,200,000 individuals of whom 74,563 resulted positive to SARS-CoV-2 and 1,166,717 resulted negative, were included in the meta-analysis. Overall, 487,985 subjects had blood group A, 151,879 had group B, 52,621 had group AB, and 548,795 had group O. Group O was slightly less associated with infection, as compared to the other three blood groups (OR = 0.91, 95% CI = 0.85-0.99, p = 0.02). Conversely, group A was slightly more associated with infection, as compared to the other three groups (OR = 1.06, 95% CI = 1.00-1.13, p = 0.04). This meta-analysis shows associations between blood groups and SARS-CoV-2 infection and supports the hypothesis that blood type O may have a slightly lower risk of infection, whereas blood type A may have a slightly higher risk of infection.

Role of ABO Blood Group in SARS-CoV-2 Infection in Households

An association between certain ABO/Rh blood groups and susceptibility to SARS-CoV-2 infection has been proposed for adults, although this remains controversial. In children and adolescents, the relationship is unclear due to a lack of robust data. Here, we investigated the association of ABO/Rh blood groups and SARS-CoV-2 in a multi-center study comprising 163 households with 281 children and 355 adults and at least one SARS-CoV-2 seropositive individual as determined by three independent assays as a proxy for previous infection. In line with previous findings, we found a higher frequency of blood group A (+ 6%) and a lower frequency of blood group O (−6%) among the SARS-CoV-2 seropositive adults compared to the seronegative ones. This trend was not seen in children. In contrast, SARS-CoV-2 seropositive children had a significantly lower frequency of Rh-positive blood groups. ABO compatibility did not seem to play a role in SARS-CoV-2 transmission within the families. A correction for family clusters was performed and estimated fixed effects of the blood group on the risk of SARS-CoV-2 seropositivity and symptomatic infection were determined. Although we found a different distribution of blood groups in seropositive individuals compared to the reference population, the risk of SARS-CoV-2 seropositivity or symptomatic infection was not increased in children or in adults with blood group A or AB versus O or B. Increasing age was the only parameter positively correlating with the risk of SARS-CoV-2 infection. In conclusion, specific ABO/Rh blood groups and ABO compatibility appear not to predispose for SARS-CoV-2 susceptibility in children.

Clinical picture and long-term symptoms of SARS-CoV-2 infection in an Italian pediatric population

Background

SARS-CoV-2 infection in the pediatric age group has a milder course than in adults, but in some cases even children may present with severe forms or develop long-term consequences. The aim of this study was to analyze the clinical features, long-term effects, lifestyle changes and psychological effects of SARS-CoV-2 infection in a pediatric sample of the Italian population.

Methods

We conducted a telephone survey among 3075 children infected with SARS-CoV-2 in the Latina Local Health Authority. Outcomes included: clinical features of infection, long-term symptoms, lifestyle changes and emotional symptoms during the illness. The information obtained was automatically linked to a spreadsheet and analyzed.

Results

One thousand four hundred thirteen children agreed to participate in the study; the mean age was 112.8 ± 21.9 months. Children were infected mainly inside familial clusters (59.6%; n = 842); 99% (n = 1399) of children were asymptomatic or exhibited mild symptoms. 20% (n = 259) of children experienced long-term symptoms; risk factors were: older age, higher body mass index and longer duration of infection.

Throughout the period of infection, children spent most of the time on devices like tv-video, social media and mobile phone for non-educational activities. 58.8% (n = 620) of parents expressed a negative opinion about distance learning. Finally, we observed that 49,6% (n = 532) of children experienced psychological symptoms during quarantine period.

Conclusion

Despite a lower susceptibility to COVID-19 in children, it is important to keep the focus high in children, both because of the possible long symptoms after infection and the impact on a children’s mental and physical health due to pandemic. We believe that the return to school or other extracurricular activities are important to correct some of the risk factors for the long COVID syndrome, as obesity, and to limit the cultural damage generated by distance learning and psychological effects related to restrictive measures.

Association of ABO blood group with respiratory disease hospitalization and severe outcomes: a retrospective cohort study in blood donors

OBJECTIVES

Environmental, socioeconomic, and genetic factors all are associated with respiratory diseases. We aimed to investigate the association between the ABO blood group and the susceptibility to respiratory diseases.

METHODS

We constructed a retrospective cohort study of blood donors in Shaanxi, China between January 1, 2012, and December 31, 2018, to investigate the impacts of the ABO blood group on the risk of hospitalization due to respiratory diseases.

RESULTS

Of 1,686,263 enrolled participants (680,788 females), 26,597 were admitted to the hospital for respiratory diseases. Compared with blood group O, blood groups A, B, and AB all demonstrated a higher risk for diseases of the upper respiratory tract (International Classification of Diseases, Tenth Revision: J30-J39) (ARR (Adjusted relative risk) 1.139, 95% confidence interval [1.106-1.225]; 1.095 [1.019-1.177]; 1.178 [1.067-1.30], respectively). Conversely, blood group A was found to have a lower risk (0.86 [0.747-0.991]) for influenza (J09-J11) and blood group B had a lower risk for pneumonia (J12-J18) (0.911 [0.851-0.976]) than blood group O. The duration of hospitalization was significantly different across the blood groups in J09-J11 and J30-J39 (P <0.05).

CONCLUSION

The blood group appears to be a prognostic factor in differentiating the occurrence of specific respiratory diseases and duration.

A common TMPRSS2 variant has a protective effect against severe COVID-19

BACKGROUND

The human protein transmembrane protease serine type 2 (TMPRSS2) plays a key role in SARS-CoV-2 infection, as it is required to activate the virus' spike protein, facilitating entry into target cells. We hypothesized that naturally-occurring TMPRSS2 human genetic variants affecting the structure and function of the TMPRSS2 protein may modulate the severity of SARS-CoV-2 infection.

METHODS

We focused on the only common TMPRSS2 non-synonymous variant predicted to be damaging (rs12329760 C>T, p.V160M), which has a minor allele frequency ranging from 0.14 in Ashkenazi Jewish to 0.38 in East Asians. We analysed the association between the rs12329760 and COVID-19 severity in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units recruited as part of the GenOMICC (Genetics Of Mortality In Critical Care) study. Logistic regression analyses were adjusted for sex, age and deprivation index. For in vitro studies, HEK293 cells were co-transfected with ACE2 and either TMPRSS2 wild type or mutant (TMPRSS2V160M). A SARS-CoV-2 pseudovirus entry assay was used to investigate the ability of TMPRSS2V160M to promote viral entry.

RESULTS

We show that the T allele of rs12329760 is associated with a reduced likelihood of developing severe COVID-19 (OR 0.87, 95%CI:0.79-0.97, p = 0.01). This association was stronger in homozygous individuals when compared to the general population (OR 0.65, 95%CI:0.50-0.84, p = 1.3 × 10-3). We demonstrate in vitro that this variant, which causes the amino acid substitution valine to methionine, affects the catalytic activity of TMPRSS2 and is less able to support SARS-CoV-2 spike-mediated entry into cells.

CONCLUSION

TMPRSS2 rs12329760 is a common variant associated with a significantly decreased risk of severe COVID-19. Further studies are needed to assess the expression of TMPRSS2 across different age groups. Moreover, our results identify TMPRSS2 as a promising drug target, with a potential role for camostat mesilate, a drug approved for the treatment of chronic pancreatitis and postoperative reflux esophagitis, in the treatment of COVID-19. Clinical trials are needed to confirm this.

ABO Blood System and COVID-19 Susceptibility: Anti-A and Anti-B Antibodies Are the Key Points

The implication of the ABO blood group in COVID-19 disease was formulated early, at the beginning of the COVID-19 pandemic more than 2 years ago. It has now been established that the A blood group is associated with more susceptibility and severe symptoms of COVID-19, while the O blood group shows protection against viral infection. In this review, we summarize the underlying pathophysiology of ABO blood groups and COVID-19 to explain the molecular aspects behind the protective mechanism in the O blood group. A or B antigens are not associated with a different risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than that of other antigens. In this case, the cornerstone is natural anti-A and anti-B antibodies from the ABO system. They are capable of interfering with the S protein (SARS-CoV-2) and angiotensin-converting enzyme 2 (ACE2; host cell receptor), thereby conferring protection to patients with sufficient antibodies (O blood group). Indeed, the titers of natural antibodies and the IgG isotype (specific to the O blood group) may be determinants of susceptibility and severity. Moreover, older adults are associated with a higher risk of bad outcomes due to the lack of antibodies and the upregulation of ACE2 expression during senescence. A better understanding of the role of the molecular mechanism of ABO blood groups in COVID-19 facilitates better prognostic stratification of the disease. Furthermore, it could represent an opportunity for new therapeutic strategies.