Assessment of the Relationship between COVID-19 infection and Glucose Levels in Related to ABO Group Among Diabetes Patients in Iraq

COV-19 has been quickly spreading in the world, producing lung inflammation and abrupt, even deadly, pulmonary collapse, COV-19were much higher in diabetic patients than in non-diabetic pa-tients. Diabetes is one of the primary causes of illness and death, and its prevalence is projected to increase rapidly over the next several decades. This investigation sought to determine how COVID-19 influenced the levels of glucose in the blood of patients diagnosed with type 1 and type 2 diabetes (DM), as well as whether or not the levels of glucose returned to normal following a recovery period of one month. Addi-tionally, there was a connection between ABO blood type and the severity of COV-19. The current study was to how COV-19 affected ABO group distribution and blood glucose levels in people who suffer from type 1 and 2 diabetes (DM). Study design: This study included ninety (90) patient divided into three groups: diabetes patient group (30) sample (control), 30 sample of DM with COV-19group and 30 sample recovery from Covid 19 after period one month of recovery, determination of the above mentioned blood groups was performed using manual method, and glucose levels measured of DM by diabetes device. The study demonstrated a relation between blood type ABO and COV-19, with type B blood being the most influenced by COV-19 in patients with type 2 diabetes, whereas there were no significant variations between blood types in those who suffer from type 1 diabetes. In type 1, 2 diabetic patients, no significant differences in blood glucose levels were found between diabetic patients with COV-19 and the recovery group from COV-19. The study displayed that the severity of COV-19 disease associated with B blood type in patients who suffer from type 2 diabetes and Cov-19 has no direct impact on blood glucose levels.Copyright © 2023, Colegio de Farmaceuticos de la Provincia de Buenos Aires. All rights reserved.

Association Between ABO Blood Group System and COVID-19 Severity.

OBJECTIVES: A possible association between blood group systems (ABO and Rh) and coronavirus disease 2019 (COVID-19) severity has recently been investigated by various studies with conflicting results. However, due to variations in the prevalence of the ABO and Rh blood groups in different populations, their association with COVID-19 might be varied as well. Therefore, we conducted this study on Libyan participants to further investigate this association and make population-based data available to the worldwide scientific community. METHODS: In this case-control study, ABO and Rh blood groups in 419 confirmed COVID-19 cases in Zawia, Libya, and 271 healthy controls were compared using descriptive statistics and χ 2 tests. RESULTS: Blood group A was significantly more prevalent in patients with severe COVID-19 (64/125; 51.2%) than in patients with nonsevere COVID-19 (108/294, 36.7%) (P < .034), whereas the O blood group prevalence was higher in nonsevere COVID-19 cases (131/294, 44.5%) compared with severe cases (43/125, 34.4%) (P < .001). CONCLUSIONS: The results showed a significant association between blood group A and the severity of COVID-19, whereas patients with blood group O showed a low risk of developing severe COVID-19 infection. No significant association was found between Rh and susceptibility/severity of the disease.

Reduced susceptibility to COVID-19 associated with ABO blood group and pre-existing anti-A and anti-B antibodies.

BACKGROUND: Susceptibility to severe acute respiratory syndrome coronavirus 2 shows individual variability in un-vaccinated and previously un-exposed individuals. We investigated the impact of ABO blood group, titers of anti-A and anti-B, other blood group antigens, and the extracellular deposition of ABH antigens as controlled by secretor fucosyltransferase 2 (FUT2) status. STUDY DESIGN AND METHODS: We studied incidents in three different hospitals between April to September 2020, where un-diagnosed coronavirus disease 2019 (COVID-19) patients were cared for by health care workers without use of personal protection and with close contact while delivering therapy. We recruited 108 exposed staff, of whom 34 were diagnosed with COVID-19. ABO blood type, titer of anti-A and -B, blood group specific alleles, and secretor status were determined. RESULTS: Blood group O was associated with lower risk of COVID-19 (OR 0.39, 95 %CI (0.16-0.92), p = 0.03) compared to non-O, i.e., blood groups A, B and AB. High titer anti-A immunoglobulin G (IgG) compared to low titer was associated with lower risk of COVID-19 (OR 0.24 95 %CI (0.07-0.78), p = 0.017). High titer of anti-B immunoglobulin M (IgM) compared to no anti-B (IgM) was associated with lower risk of COVID-19 (OR 0.16, 95 %CI (0.039-0.608), p = 0.006) and the same applies to low titer anti-B (IgM) compared to no titer (OR 0.23, 95 %CI (0.07-0.72), p = 0.012). The 33Pro variant in Integrin beta-3, that is part of human platelet antigen 1b (HPA-1b), was associated with lower risk of COVID-19 (OR 0.23, 95 %CI (0.034-0.86), p = 0.028). CONCLUSION: Our data showed that blood group O, anti-A (IgG) titer, anti-B (IgM) titer as well as HPA-1b are associated with lower risk for COVID-19.

An Insight into Association Between COVID-19 Infection and ABO Blood Group

Coronavirus disease 2019 (COVID-19), a pandemic that is triggered by a novel coronavirus, named severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) or 2019-nCoV, causes primarily respiratory discomfort along with other mild symptoms/no symptoms, leading to severe illness and death, if proper care is not taken. At present, COVID-19 is the resilient reason for a large number of human casualties worldwide as well as a cause of crucial economic loss posturing global threat. There is a necessity of intensive research to elucidate the pathogenic mechanisms of COVID-19, which would assist in understating the susceptibility towards the infection as well as prompt development of effective prevention and treatment strategies. Over the years, clinical studies have indicated the risk of various pathogenic infections prejudiced due to preexisting chronic diseases as well as ABO blood group types to a larger extent. In line of this, current COVID-19 infection-associated clinical studies intensely endorse the relationship of blood group type of individual and risk of COVID-19 infection. In this chapter, various clinical studies from January 2020 to June 2020 have been summarized to highlight the eminence of ABO blood group and COVID-19 infection susceptibility in human population. These reports evidently support the fact that individuals with A histo blood group were found to be more vulnerable to COVID-19 infection whereas individuals with blood group O were less likely to get infected with virus. To get deeper insight in this fact, many more studies are desirable in order to further explicate the promising protective role of the blood group O and it will be supportive for designing and planning several additional countermeasures against COVID-19 infection. © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 2021.

Ssessment of post-vaccination collective immunity against new coronavirus infection (COVID-19) among servicemen of the armed forces of the Russian Federation

The recent vaccination campaign targeting the new coronavirus infection (COVID-19) carried out in the Armed Forces of the Russian Federation, on the background of the current unstable global pandemic situation, makes it necessary to study post-vaccination population immunity to the SARS-CoV-2 virus and thus identify key features of immunity in organized military collectives. In the future, this will make it possible to objectively assess the risks of a worsening pandemic situation, effectively adjust the ongoing sanitary and anti-epidemic measures aimed at preserving and strengthening the health of military personnel, as one of the main conditions for maintaining the combat readiness of the Armed Forces of the Russian Federation. During a study conducted on epidemic indications, it was found that vaccination with Gam-Covid-Vac contributes to the formation of collective immunity with 95% effectiveness. A gender-based analysis of the immune response showed that the proportion of persons who lack class G immunoglobulins to SARS-CoV-2 among females is twice than that among men (9.3% and 4.7%, respectively). Seroprevalence indicators, classified by blood group, range from 94.4% (AB (IV) Rh-) to 97.4% (A (II) Rh-). There were no significant differences in seroprevalence between groups of people with different blood groups;however, the highest value of seroprevalence was seen among military personnel with blood group A (II) Rh-. In this context, it is advisable to continue monitoring the formation of immunity in individuals with various blood groups. The results obtained made it possible to form a primary medical and social "portrait" of a serviceman with the most adequate immune response to the introduction of the Gam-Covid-Vac vaccine (a man under the age of 20 with blood type A (II) Rh-) and to draw a conclusion about the high effectiveness of vaccination in military units (formations) staffed by conscripts and military educational organizations.

Relationship between AB0 and Rh Blood Groups in COVID-19 Patients and In-Hospital Mortality

According to the Berlin classification10, Group 3 consisted of patients who had PaO2/FiO2 between 200-300 mild ARDS (Acute respiratory distress syndrome) or more than 300 non-ARDS and whose clinical condition is not severe, nasal oxygen support was sufficient. Patients older than 18 years of age, whose blood group information was registered in the hospital database system, and who had positive PCR (Polymerase Chain Reaction) test results were included in the study. Patients whose blood group information was not registered in the hospital database system and PCR test results were negative, and who were younger than 18 years of age were excluded from the study. [...]we did not find a significant difference between AB0 and Rh blood groups and disease severity in patients with mild clinical findings and intensive care patients with moderate-severe clinical findings.

Prediction of COVID-19 infection severity using ABO blood group types and Rh factor

Background & Objective: Biological markers for the prediction of acquiring Covid-19 risk are deficient and there is a dire need of immediate research data. The objective of the study was to predict the link of ABO blood group types along with Rh factor distribution with the severity of Covid-19. Methods: This was an observational cross-sectional survey conducted in medicine department of Pakistan Ordnance Factory Hospital, Wah Cantt Pakistan, from August 2020 to December 2020 after approval of IRB. Participants tested positive for presence of Covid-19 infection by polymerase chain reaction (PCR) were included in the study. Covid-19 infection severity was measured through mild, moderate and severe disease categories and analyzed. ABO blood group and Rh subgroups data for all the Covid-19 infected patients were obtained from the laboratory section of the hospital and analyzed. Data was entered in SPSS v 26 and analyzed. Cox regression model was used to find out the severity of Covid-19. Results: Total 248 patients were included;75% patients were male and 25% were females. The mean age of the patients was 52.77+or-15.58 years. A very significant association was found between ABO blood group types, Rh factor antigen and severity of Covid-19 (p=0.001). When stratified ABO, Rh antigen blood group with health status of all patients there was a very significant association between them (p=0.013). An insignificant association between male and female odds ratio of ABO blood group types but blood group B, Rh positive antigen was more susceptible in Covid-19 positive patients. Conclusion: There is a link between ABO blood group types along with Rh factor antigen (B+ and O+) with the severity of Covid-19 positive patients. ABO blood group types and Rh factor can be used as a potential marker/tool to predict the susceptibility of acquiring Covid-19 infection as well as for severity of the infection.

Relationship between the ABO blood group and Rhesus factors with COVID-19 susceptibility.

INTRODUCTION: The molecular research has raised copious hypotheses about different molecular effects on the variable expression of the current virus on the human body. The present prospective study aims to determine clinically as well as statistically, the relation between ABO blood groups and Rhesus (Rh) factor and the severity of the Covid-19 virus. RESEARCH DESIGN AND METHODS: We conducted a prospective, single-centered study at The Combined Military Hospital Lahore, Pakistan. Details of only those patients who exhibit COVID-19 symptoms were included. The odds ratios with a 95% confidence interval and the chi-square test of blood groups and Rhesus factor was also conducted individually with the severity of disease, outcomes, and respiratory symptoms. P-values less than 0.05 was considered significant. RESULTS: The chi-square test and odd ratio yielded no significant results when the covid-19 status was compared with the Rhesus factor (p-value > 0.05). However, the results were found to be significant when associations were run between Covid-19 status and all the blood groups (p-value < 0.05). CONCLUSION: According to the analytical results of the present study, protective nature of all the blood antigens (A, B, AB, none) was observed in patients presenting with Covid-19 symptoms of varying severity.

Associations of ABO and Rhesus D blood groups with phenome-wide disease incidence: A 41-year retrospective cohort study of 482,914 patients.

Background: Whether natural selection may have attributed to the observed blood group frequency differences between populations remains debatable. The ABO system has been associated with several diseases and recently also with susceptibility to COVID-19 infection. Associative studies of the RhD system and diseases are sparser. A large disease-wide risk analysis may further elucidate the relationship between the ABO/RhD blood groups and disease incidence. Methods: We performed a systematic log-linear quasi-Poisson regression analysis of the ABO/RhD blood groups across 1,312 phecode diagnoses. Unlike prior studies, we determined the incidence rate ratio for each individual ABO blood group relative to all other ABO blood groups as opposed to using blood group O as the reference. Moreover, we used up to 41 years of nationwide Danish follow-up data, and a disease categorization scheme specifically developed for diagnosis-wide analysis. Further, we determined associations between the ABO/RhD blood groups and the age at the first diagnosis. Estimates were adjusted for multiple testing. Results: The retrospective cohort included 482,914 Danish patients (60.4% females). The incidence rate ratios (IRRs) of 101 phecodes were found statistically significant between the ABO blood groups, while the IRRs of 28 phecodes were found statistically significant for the RhD blood group. The associations included cancers and musculoskeletal-, genitourinary-, endocrinal-, infectious-, cardiovascular-, and gastrointestinal diseases. Conclusions: We found associations of disease-wide susceptibility differences between the blood groups of the ABO and RhD systems, including cancer of the tongue, monocytic leukemia, cervical cancer, osteoarthrosis, asthma, and HIV- and hepatitis B infection. We found marginal evidence of associations between the blood groups and the age at first diagnosis. Funding: Novo Nordisk Foundation and the Innovation Fund Denmark.

Immunogenetic Predisposition to SARS-CoV-2 Infection.

Herein, we included 527 individuals from two Hospitals, Chemnitz and University-Hospital Leipzig. In total, 199 were negative for PCR and 328 were positive upon first admission. We used next generation sequencing for HLA-A, B, C, DRB1, DRB345, DQA1, DQB1, DPA1, and DPB1, and in some cases, HLA-E, F, G, and H. Furthermore, we molecularly defined 22 blood group systems comprising 26 genes and 5 platelet antigen genes. We observed a significant enrichment of homozygosity for DQA/DQB in the positive group. Within the negative subjects, HLA-B*57:01, HLA-B*55:01, DRB1*13:01, and DRB1*01:01 were enriched, and in the positive group, homozygosity for DQA/DQB, DRB1*09:01, and DRB1*15:01 was observed. DQA1*01:01, DQA1*02:01, and DQA1*01:03 were enriched in the negative group. HLA-DQB1*06:02 was enriched in the positive group, and HLA-DQB1*05:01 and HLA-DQB1*06:03 were enriched in the negative group. For the blood group systems MNS, RH, LE, FY, JK, YT, DO, and KN, enrichment was seen in both groups, depending on the antigen under observation. Homozygosity for D-positive RHD alleles, as well as the phenotypes M-N+ of the MNS blood group system and Yk(a-) of the KN system, were enriched in the positive group. All of these significances disappeared upon correction. Subjects who carried homozygous HPA-1a were more frequent in the negative group, contrasting with the finding that HPA-1ab was enriched in the positive group.

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.

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

BACKGROUND: Previous studies have reported Blood type O to confer a lower risk of SARS-CoV-2 infection, while secretor status and other blood groups have been suspected to have a similar effect as well. STUDY DESIGN AND METHODS: To determine whether any other blood groups influence testing positive for SARS-CoV-2, COVID-19 severity, or prolonged COVID-19, we used a large cohort of 650,156 Danish blood donors with varying available data for secretor status and blood groups ABO, Rh, Colton, Duffy, Diego, Dombrock, Kell, Kidd, Knops, Lewis, Lutheran, MNS, P1PK, Vel, and Yt. Of these, 36,068 tested positive for SARS-CoV-2 whereas 614,088 tested negative between 2020-02-17 and 2021-08-04. Associations between infection and blood groups were assessed using logistic regression models with sex and age as covariates. RESULTS: The Lewis blood group antigen Lea displayed strongly reduced SARS-CoV-2 susceptibility OR 0.85 CI[0.79-0.93] p < .001. Compared to blood type O, the blood types B, A, and AB were found more susceptible toward infection with ORs 1.1 CI[1.06-1.14] p < .001, 1.17 CI[1.14-1.2] p < .001, and 1.2 CI[1.14-1.26] p < .001, respectively. No susceptibility associations were found for the other 13 blood groups investigated. There was no association between any blood groups and COVID-19 hospitalization or long COVID-19. No secretor status associations were found. DISCUSSION: This study uncovers a new association to reduced SARS-CoV-2 susceptibility for Lewis type Lea and confirms the previous link to blood group O. The new association to Lea could be explained by a link between mucosal microbiome and SARS-CoV-2.

EVALUATION OF HUMAN ABO BLOOD GROUPS AND BLOOD COMPONENTS AMONG IRAQI PATIENTS INFECTED WITH CORONAVIRUS DISEASE 2019 (COVID-19).

OBJECTIVE: The aim: To evaluate the differences in blood groups, gender and type of Rh factor, as well as the levels of hemoglobin, white blood cells and platelets among patients infected with COVID-19. PATIENTS AND METHODS: Materials and methods: A cross-sectional study was performed on 202 patients diagnosed with sever COVID-19 infection who were admitted to the Al-Shefaa center in Al- Hakeem hospital in Al-Najef city.Haematological investigations involved the types of blood groups, Rh factors, haemoglobin (Hb), white blood cells (WBCs), and platelets. In addition, the demographic features including age, gender and presence of any prescribed medications before or at the time of the study were also included. RESULTS: Results: This study indicated that COVID-19 infected patients with type A blood group are at higher risk of hospitalization than other blood groups, and the majority of these patients were Rh positive. Additionally, WBCs counts indicated that the majority of patients had increased risk of getting infections which demonstrated lower WBC counts than normal. Platelet and Hb levels were normal for the majority of patients. CONCLUSION: Conclusions: The findings of this study may help in the diagnosis of the pandemic infection with COVID-19, and prediction of the incidence of some complications caused by COVID-19. Further researches are warranted to confirm our findings.

Association of blood group A with hospital comorbidity in patients infected by SARS-CoV-2.

Background and objectives: In the pandemic caused by SARS-CoV-2, identifying which risk factors are associated with the most serious forms of the disease is important. Blood group A has been presented in various studies as a poor prognostic factor. The objective of this study was to evaluate whether patients with blood group A were associated with more important comorbidities, measured by the Charlson Index, which may explain their worse clinical evolution. Patients and methods: A prospective and consecutive study examined 100 patients diagnosed with COVID-19 and admitted in March 2020. A multivariate linear regression model was used to evaluate the association of blood group A with the Charlson Index. Results: Patients in group A had a higher Charlson Index (P = .037), rate of lymphopenia (P = .039) and thrombopenia (P = .014), and hospital mortality (P = .044). Blood group A was an independent factor associated with the Charlson Index (B 0.582, 95% CI 0.02-1.14, P = .041). Conclusions: Group A was independently associated with greater comorbidity, associated with an increase of 0.582 points in the Charlson Index compared to other blood groups. It was also associated with lower hospital mortality.

Fundamento y objetivos: En la pandemia provocada por SARS-CoV-2, es importante identificar qué factores de riesgo se asocian a las formas más graves de la enfermedad. El grupo sanguíneo A se ha presentado en diversos estudios como factor de mal pronóstico. El objetivo de este estudio radica en evaluar si los pacientes de grupo sanguíneo O asocian comorbilidades más importantes, medido por el Índice de Charlson, que puedan justificar también su peor evolución clínica. Pacientes y método: Estudio prospectivo y consecutivo con 100 pacientes diagnosticados de COVID-19 ingresados en marzo de 2020. Se empleó un modelo de regresión lineal multivariante para evaluar la asociación del grupo sanguíneo A con el Índice de Charlson. Resultados: Los pacientes del grupo A presentaron mayor Índice de Charlson (P = .037), linfopenia (P = .039), trombopenia (P = .014) y mortalidad hospitalaria (P = .044).El grupo sanguíneo A demostró ser un factor independiente asociado a dicho índice [B 0.582, IC 95% (0.02­1.14), P = .041]. Conclusiones: El grupo A se asocia de forma independiente a mayor comorbilidad, asociando un incremento de 0.582 puntos en el índice de Charlson con respecto al resto de grupos sanguíneos. Además, asocia una tendencia de menor mortalidad hospitalaria.

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.

The effects of blood group type on COVID-19 recovery in patients

Background: The arising Covid infection 2019 is rapidly spreading over the world and has been named a pandemic by the World Health Organization (WHO). The ABO blood group has been linked to the susceptibility to viral infection in the past. According to research, blood groups A and O are associated with a higher and lower risk of coronavirus disease 2019 positivity. Objectives: The goal of the study was to see if there was a link between ABO blood type and COVID-19 susceptibility in patients recovering in Baghdad and Hilla hospitals, and if the former could be used as a biomarker for the latter.

International Society of Blood Transfusion Working Party on Red Cell Immunogenetics and Blood Group Terminology Report of Basel and three virtual business meetings: Update on blood group systems.

BACKGROUND AND OBJECTIVES: Under the ISBT, the Working Party (WP) for Red Cell Immunogenetics and Blood Group Terminology is charged with ratifying blood group systems, antigens and alleles. This report presents the outcomes from four WP business meetings, one located in Basel in 2019 and three held as virtual meetings during the COVID-19 pandemic in 2020 and 2021. MATERIALS AND METHODS: As in previous meetings, matters pertaining to blood group antigen nomenclature were discussed. New blood group systems and antigens were approved and named according to the serologic, genetic, biochemical and cell biological evidence presented. RESULTS: Seven new blood group systems, KANNO (defined numerically as ISBT 037), SID (038), CTL2 (039), PEL (040), MAM (041), EMM (042) and ABCC1 (043) were ratified. Two (039 and 043) were de novo discoveries, and the remainder comprised reported antigens where the causal genes were previously unknown. A further 15 blood group antigens were added to the existing blood group systems: MNS (002), RH (004), LU (005), DI (010), SC (013), GE (020), KN (022), JMH (026) and RHAG (030). CONCLUSION: The ISBT now recognizes 378 antigens, of which 345 are clustered within 43 blood group systems while 33 still have an unknown genetic basis. The ongoing discovery of new blood group systems and antigens underscores the diverse and complex biology of the red cell membrane. The WP continues to update the blood group antigen tables and the allele nomenclature tables. These can be found on the ISBT website (http://www.isbtweb.org/working-parties/red-cell-immunogenetics-and-blood-group-terminology/).

ABO-Rh Blood Types and Clinical Consequences of COVID-19 Infection.

Aim and Background: Because of there is no sufficient evidence showing a relationship between blood types and severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, this study was planned to investigate the effects of ABO blood group on the clinical outcomes of SARS-CoV-2 infection. Patients and Methods: The data of the patients were examined retrospectively. The patients who were hospitalized in wards or intensive care unit, constituted the study group. The patients who presented to the hospital because of other causes and whose blood type examinations were performed, were included in the control group. Results: The study group consisted of 406 six patients were diagnosed with SARS-CoV-2 infection. Control group consisted of 38079 patients whose blood group was determined for any reason in the same period. The rate of Rh negativity was significantly higher in the patient group (p = 0,01). Hospitalization duration in intensive care was significantly longer in the blood type A and AB groups compared to the blood type O group (p = 0,03). Conclusion: Our results are in agreement with other studies suggesting that blood group O individuals are somewhat more resistant to clinically overt infection with SARS-CoV-2 than other blood groups. In addition, Rh negativity may also be an individual risk factor for SARS-CoV-2 infection.

Association of blood group A with hospital comorbidity in patients infected by SARS-CoV-2. / Asociación del grupo sanguíneo A con mayor comorbilidad hospitalaria en pacientes infectados por SARS-CoV-2.

BACKGROUND AND OBJECTIVES: In the pandemic caused by SARS-CoV-2, identifying which risk factors are associated with the most serious forms of the disease is important. Blood group A has been presented in various studies as a poor prognostic factor. The objective of this study was to evaluate whether patients with blood group A were associated with more important comorbidities, measured by the Charlson Index, which may explain their worse clinical evolution. PATIENTS AND METHODS: A prospective and consecutive study examined 100 patients diagnosed with COVID-19 and admitted in March 2020. A multivariate linear regression model was used to evaluate the association of blood group A with the Charlson Index. RESULTS: Patients in group A had a higher Charlson Index (P=.037), rate of lymphopenia (P=.039) and thrombopenia (P=.014), and hospital mortality (P=.044). Blood group A was an independent factor associated with the Charlson Index (B 0.582, 95% CI 0.02-1.14, P=0.041). CONCLUSIONS: Group A was independently associated with greater comorbidity, associated with an increase of 0.582 points in the Charlson Index compared to other blood groups. It was also associated with lower hospital mortality.

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.