Abstract

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.

Abstract

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.

Abstract

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).

Abstract

BACKGROUND Following the first reports in the literature, the association between the ABO blood group and SARS-CoV-2 infection has been investigated by a number of studies, although with varying results. The main object of this systematic review was to assess the relationship between the ABO blood group and the occurrence and severity of COVID-19. MATERIALS AND METHODS A systematic literature search using appropriate MeSH terms was performed through Medline and PubMed. The outcomes considered were the prevalence of the blood group O vs non-O types in SARS-CoV-2 infected and non-infected subjects, and the severity of SARS-CoV-2 infection according to ABO group. The methodological quality of the studies included in the analysis was assessed with the Newcastle-Ottawa Scale, and the overall quality of the available evidence using the GRADE system. Benchmarks used to evaluate the effect size were odd ratios (ORs) for case control studies and risk ratios (RRs) for cohort studies. RESULTS Twenty-one studies were included in the analysis. Overall, individuals with group O had a lower infection rate compared to individuals of non-O group (OR: 0.81; 95% CI: 0.75, 0.86). However, the difference in the effect size was significantly lower in cohort studies compared to case control studies. No evidence was found indicating an effect of the O type on the disease severity in the infected patients. DISCUSSION We have found low/very low evidence that group O individuals are less susceptible to SARS-CoV-2 infection compared to those in the non-O group. No evidence was found indicating an effect of the O type on disease severity in SARS-CoV-2 infection.

Abstract

INTRODUCTION Previous studies have linked the relationship between ABO blood group and COVID-19 infection. However, existing evidence is preliminary and controversial. This meta-analysis sought to identify studies that describe COVID-19 and ABO blood group. METHODOLOGY A literature search was conducted from PubMed, Web of Science, MedRxiv, BioRxiv and Google Scholar databases. Members of cases and controls were extracted from collected studies. Pooled Odds ratio (OR) and 95% confidence interval (95%CI) were calculated and interpreted from extracted data. Publication bias and sensitivity analysis were also applied to confirm our discovery. RESULTS Total 13,600 patients and 3,445,047 controls were included in the study. Compared to other ABO blood group, blood group O was associated with a lower risk of COVID-19 infection (OR = 0.76, 95%CI 0.66-0.84), while blood group A and AB was associated with a higher risk (OR = 1.25, 95%CI 1.10-1.41; OR = 1.13, 95%CI 1.04-1.23, respectively). In the subgroup analysis, the relationship between blood group A, O and COVID-19 infection remained stable among Chinese, European and Eastern Mediterranean populations. In American population, blood groups B was linked with increased risk of COVID-19 infection (OR = 1.21, 95%CI 1.09-1.35). CONCLUSIONS Our data suggested that individuals with blood types A and AB are more susceptible to COVID-19, while people with blood type O are less susceptible to infection. More research is needed to clarify the precise role of the ABO blood group in COVID-19 infection to address the global question.

Abstract

Background Numerous studies investigate the association between the ABO blood groups and the occurrence of COVID-19 infection;discordant findings were reported Therefore, the purpose of this meta-analysis was to evaluate the existing evidence on the susceptibility of the ABO blood group to COVID-19 infection Methods Systematically searched published articles in PubMed, Google Scholar, Scopus, and EMBASE between 1 st January 2020 and 21 st March 2021 After quality control and the exclusion of irrelevant studies, 12 studies were included in the final analysis Results Although the random-effect meta-analysis revealed a large heterogeneity among studies, I 2 = 99 197% The pooled event rates and (95% CIs) for A, O, B, and AB blood group were 0 459 (95%CI: 0 358–0 441), 0 342 (95%CI: 0 298–0 374), 0 180 (95%CI: 0 150–0 214), and 0 076 (95%CI: 0 055–0 127), respectively These results indicated that the COVID-19 infection rate was higher in persons with blood group A > O > B > AB Overall, the ABO blood group's vulnerability to COVID-19 infection was statistically significant (pooled p -value<0 001) Conclusion This meta-analysis offers a further indication of blood group A individuals' vulnerability to COVID-19 infection, and blood type AB are linked to a lower risk of COVID-19 infection

Abstract

BACKGROUND Numerous studies investigate the association between the ABO blood groups and the occurrence of COVID-19 infection; discordant findings were reported. Therefore, the purpose of this meta-analysis was to evaluate the existing evidence on the susceptibility of the ABO blood group to COVID-19 infection. METHODS Systematically searched published articles in PubMed, Google Scholar, Scopus, and EMBASE between 1 st January 2020 and 21 st March 2021. After quality control and the exclusion of irrelevant studies, 16 studies were included in the final analysis. RESULTS Although the random-effect meta-analysis revealed a large heterogeneity among studies, I 2 = 99.197 %. The pooled event rates and (95 % CIs) for A, O, B, and AB blood group were 0.459 (95 %CI: 0.358-0.441), 0.342 (95 %CI: 0.298-0.374), 0.180 (95 %CI: 0.150-0.214), and 0.076 (95 %CI: 0.055-0.127), respectively. These results indicated that the COVID-19 infection rate was higher in persons with blood group A > O > B > AB. Overall, the ABO blood group's vulnerability to COVID-19 infection was statistically significant (pooled p -value<0.001). CONCLUSION This meta-analysis offers a further indication of blood group A individuals' vulnerability to COVID-19 infection, and blood type AB are linked to a lower risk of COVID-19 infection.

Abstract

BACKGROUND AND AIMS The COVID-19 spreads rapidly around the world which has brought a global health crisis. The pathogen of COVID-19 is SARS-COV-2, and previous studies have proposed the relationship between ABO blood group and coronavirus. Here, we aim to delve into the association between ABO blood group and COVID-19 infection, severity and demise. METHODS The relevant studies were retrieved from five databases: PubMed, MedRxiv, BioRxiv,Web of Science and CNKI. Members of cases(symptomatic cases, severe cases, died cases) and controls(asymptomatic controls, non-severe controls, alive controls) were extracted from collected studies. Odds ratios (OR) and 95% confidence intervals (CI) were calculated and interpreted from extracted data. Publication bias and sensitivity analysis were also applied to confirm our discovery. RESULTS Overall 31,100 samples were included in the analysis. Compared to other ABO blood type, an increased odds of infecting COVID-19 among individuals with A blood group (OR: 1.249, 95%CI: 1.114-1.440, P < 0.001) and a decreased odds of infecting COVID-19 among individuals with blood group O (OR: 0.699, 95%CI: 0.635-0.770, P < 0.001) were found. Besides, individuals with blood group AB seems to link a higher risk to COVID-19 severity (OR: 2.424, 95%CI: 0.934-6.294) and demise (OR: 1.348, 95%CI: 0.507-3.583). Meantime, individuals with O blood group might had lower risk to COVID-19 severity (OR: 0.748, 95%CI: 0.556-1.007), and individuals with B blood group were likely to relate a lower risk to COVID-19 demise. CONCLUSIONS The current meta-analysis suggest that blood type A might be more susceptible to infect COVID-19 while blood type O might be less susceptible to infect COVID-19; there were no correlation between ABO blood group and severity or demise of COVID-19. However, more investigation and research are warranted to clarify the relationship between COVID-19 and ABO blood type.

Abstract

Introduction The relationship between ABO blood group and the incidence of COVID-19 infection and death has been investigated in several studies The reported results were controversial, so the objective of the present study is to assess the relationship between different blood groups and the onset and mortality of COVID-19 infection using meta-analysis method Methods We searched the databases using appropriate MeSH terms We screened articles on the basis of titles, abstracts, and full texts, and the articles that met the inclusion criteria were selected Quality assessment was done with the Newcastle-Ottawa Scale checklist The estimated frequency of COVID-19 infection and death in terms of ABO blood group and the overall estimate of the odd ratio between blood group with COVID-19 infection and death was done with 95% confidence interval Results The pooled frequency of blood groups A, B, O, and AB among COVID-19 infected individuals was estimated as 36 22%, 24 99%, 29 67%, and 9 29% respectively The frequency of blood groups A, B, O, and AB among the dead cases due to COVID-19 infection was estimated as 40%, 23%, 29%, and 8% respectively The odd ratio of COVID-19 infection for blood group A versus the other blood groups was estimated 1 16 (CI 95%: 1 02-1 33) The corresponding figures for blood groups O and AB versus other blood groups were estimated as 0 73 (CI 95%: 0 60-0 88) and 1 25(CI 95%: 0 84-1 86) respectively Conclusion This meta-analysis showed that individuals with blood group A are at higher risk for COVID-19 infection while those with blood group O are at lower risk Although the odds ratio of death for AB blood group was non-significant, it was considerable

Abstract

At present, existing evidence about the association between SARS-CoV-2 infection and ABO blood group polymorphism is preliminary and controversial. In this meta-analysis we investigate this association and determine SARS-CoV-2 positive individuals' odds of having a specific blood group compared to controls. We performed a systematic search on MEDLINE and LitCovid databases for studies published through July 15, 2020. Seven studies met inclusion criteria for meta-analysis, including a total of 13 subgroups of populations (7503 SARS-CoV-2 positive cases and 2962160 controls). We analysed the odds of having each blood group among SARS-CoV-2 positive patients compared with controls. Random-effects models were used to obtain the overall pooled odds ratio (OR). Subgroup and sensitivity analyses were performed in order to explore the source of heterogeneity and results consistency. The results of our meta-analysis indicate that SARS-CoV-2 positive individuals are more likely to have blood group A (pooled OR 1.23, 95%CI: 1.09-1.40) and less likely to have blood group O (pooled OR = 0.77, 95%CI: 0.67-0.88). Further studies are needed to investigate the mechanisms at the basis of this association, which may affect the kinetics of the pandemic according to the blood group distribution within the population.