COVID-19 Susceptibility By Race, Blood Type

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COVID-19 Susceptibility By Race, Blood Type Oct 14, 2020 21:52:00 GMT

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Post by Admin on Oct 14, 2020 21:52:00 GMT

UNDERSTANDING AGE-ADJUSTED MORTALITY RATES
While there are many features of the novel coronavirus that are still unclear, this we know with certainty: The risk of dying from COVID-19 rises sharply with advanced age. About 3 in 100,000 Americans under age 45 have died from the virus, according to data submitted to the CDC through Sept. 5. The COVID-19 death rate for Americans age 45-54 rises to 22 per 100,000; more than doubles for those age 55-64 (53 per 100,000); and more than doubles among those age 65-74 (123 per 100,000). Among Americans age 75 and older, the death toll is exceedingly high: 464 people per 100,000, as shown below.

Due to this steep age gradient to COVID-19 mortality, it is important to consider the varying age distributions of America’s racial and ethnic groups. A higher share of White Americans are in the older age brackets than any other group. To illustrate this, consider that the median age of non-Hispanic White Americans is 44 years, according to the latest Census Bureau data. The comparable figure for all populations of color is considerably lower—for Asians (37), Blacks (34), Pacific Islanders (33), Indigenous (32) and especially Latinos (30), half of whom have not yet reached their 30th birthday.

Even within the same race groups, the age distribution varies—with retirement destination states such as Florida having a much higher share of older adults within their White population, for example.

Black, Indigenous, Pacific Islander and Latino Americans all have a COVID-19 death rate of roughly triple or more White Americans (age-adjusted).

So, to remove the role of age differences from COVID-19 mortality rates, we have also produced age-adjusted rates. Because mortality data is not available for all states by race and age jointly (which is preferred), we have used indirect standardization to calculate these rates. See our NOTES section for details and cautions about our method.

Adjusting the racial data we’ve collected for age differences increases the COVID-19 mortality rate for all racial and ethnic groups except for Whites, who experience a decrease, as shown below. Latinos’ rate rises the most following age-adjustment, revealing that the virus is impacting Latinos far more than would be expected based on their age profile.

While Black Americans continue to experience the highest COVID-19 mortality rate after age-adjusting, doing so also widens the gap between Black and White mortality—from 2.2 to 3.4 times as high. Mortality rates for Indigenous people rise to 3.3 times as high as Whites’ mortality impact. Rates for Latinos and Pacific Islanders also rise substantially, to 3.3 and 2.9 times as high as Whites, respectively. Finally, the Asian mortality rate—which was slightly below the White rate—rises above the White death rate (1.3 times as high), when age is taken into account. Put another way, Black, Indigenous, Pacific Islander and Latino Americans all have COVID-19 death rates of roughly triple or more the rate of White Americans (age-adjusted).

What does this mean? It indicates that many younger Americans who are Black, Latino, Indigenous or Pacific Islanders are dying of COVID-19—driving their mortality rates far above White Americans’. Despite their relative youthfulness (a protective factor against COVID), their death rates are elevated. As Brookings Institution has reported, “In every age category, Black people are dying from COVID at roughly the same rate as White people more than a decade older.”

Depending on the community, this may be due to numerous, reinforcing factors related to a higher likelihood of contracting the virus—such as greater workplace exposures, including inability to work from home or no access to sick days; living in geographic areas, housing arrangements including congregate settings (such as nursing homes, group homes, treatment centers, correctional facilities), or accessing public transportation where the virus is more easily spread. It also results from poorer outcomes after acquiring COVID-19—such as resulting from less access to testing; higher presence of underlying health conditions like diabetes, hypertension, obesity and asthma; and receiving delayed or poorer medical care, perhaps because they lack health insurance or distrust health providers or they are simply receiving inferior care. The racial disparities in COVID-19 mortality—due to these compounding, elevated risks from our systems of housing, labor force, health care, and policy responses—are the result of systemic racism.

It is important to note that, while age-adjusted mortality rates help us remove the influence of age differences in racial groups to examine disparities in outcomes, they are not the actual mortality rates experienced by these groups.

Last Edit: Oct 14, 2020 21:55:44 GMT by Admin

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COVID-19 Susceptibility By Race, Blood Type Oct 15, 2020 6:28:31 GMT

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Post by Admin on Oct 15, 2020 6:28:31 GMT

Individuals with blood type O may have lowest risk of infection; individuals with A and AB may have increased risk of severe clinical outcomes.

Two studies published today (October 14, 2020) in Blood Advances suggest people with blood type O may have a lower risk of COVID-19 infection and reduced likelihood of severe outcomes, including organ complications, if they do get sick.

As the pandemic continues, the global biomedical research community is working urgently to identify coronavirus risk factors and potential therapeutic targets. The potential role of blood type in predicting risk and complications of COVID-19 infection has emerged as an important scientific question. These new studies add evidence that there may be an association between blood type and vulnerability to COVID-19; however, additional research is needed to better understand why and what it means for patients.

Individuals with blood type O may be less vulnerable to COVID-19 infection

Blood type O may offer some protection against COVID-19 infection, according to a retrospective study . Researchers compared Danish health registry data from more than 473,000 individuals tested for COVID-19 to data from a control group of more than 2.2 million people from the general population. Among the COVID-19 positive, they found fewer people with blood type O and more people with A, B, and AB types.

The study results suggest that people with blood types A, B, or AB may be more likely to be infected with COVID-19 than people with type O. The researchers did not find any significant difference in rate of infection between A, B, and AB types. Since blood group distributions vary among ethnic subgroups, the researchers also controlled for ethnicity and maintained that fewer people with blood type O tested positive for the virus.

“It is very important to consider the proper control group because blood type prevalence may vary considerably in different ethnic groups and different countries,” said study author Torben Barington, MD, of Odense University Hospital and the University of Southern Denmark. “We have the advantage of a strong control group – Denmark is a small, ethnically homogenous country with a public health system and a central registry for lab data – so our control is population-based, giving our findings a strong foundation.”

Blood groups A and AB associated with increased risk of severe clinical outcomes of COVID-19 infection People with blood groups A or AB appear to exhibit greater COVID-19 disease severity than people with blood groups O or B, according to a separate retrospective study. Researchers examined data from 95 critically ill COVID-19 patients hospitalized in Vancouver, Canada. They found that patients with blood groups A or AB were more likely to require mechanical ventilation, suggesting that they had greater rates of lung injury from COVID-19. They also found more patients with blood group A and AB required dialysis for kidney failure.

Together, these findings suggest that patients in these two blood groups may have an increased risk of organ dysfunction or failure due to COVID-19 than people with blood types O or B. Furthermore, while people with blood types A and AB did not have longer overall hospital stays than those with types O or B, they did remain in the intensive care unit (ICU) for a longer average time, which may also signal a greater COVID-19 severity level.

“The unique part of our study is our focus on the severity effect of blood type on COVID-19. We observed this lung and kidney damage, and in future studies, we will want to tease out the effect of blood group and COVID-19 on other vital organs,” said study author Mypinder S. Sekhon, MD, of the University of British Columbia. “Of particular importance as we continue to traverse the pandemic, we now have a wide range of survivors who are exiting the acute part of COVID-19, but we need to explore mechanisms by which to risk stratify those with longer-term effects.”

References:

“Reduced prevalence of SARS-CoV-2 infection in ABO blood group O” by Mike Bogetofte Barnkob, Anton Pottegård, Henrik Støvring, Thure Mors Haunstrup, Keld Homburg, Rune Larsen, Morten Bagge Hansen, Kjell Titlestad, Bitten Aagaard, Bjarne Kuno Møller and Torben Barington, 14 October 2020, Blood Advances.
DOI: 10.1182/bloodadvances.2020002657

“The association of ABO blood group with indices of disease severity and multiorgan dysfunction in COVID-19” by Ryan L. Hoiland,Nicholas A. Fergusson, Anish R. Mitra, Donald E. G. Griesdale, Dana V. Devine, Sophie Stukas, Jennifer Cooper, Sonny Thiara, Denise Foster, Luke Y. C. Chen, Agnes Y. Y. Lee, Edward M. Conway, Cheryl L. Wellington and Mypinder S. Sekhon, 14 October 2020, Blood Advances.
DOI: 10.1182/bloodadvances.2020002623

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COVID-19 Susceptibility By Race, Blood Type Oct 16, 2020 1:31:27 GMT

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Post by Admin on Oct 16, 2020 1:31:27 GMT

Reduced prevalence of SARS-CoV-2 infection in ABO blood group O

Abstract
Identification of risk factors for contracting and developing serious illness following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is of paramount interest. Here, we performed a retrospective cohort analysis of all Danish individuals tested for SARS-CoV-2 between 27 February 2020 and 30 July 2020, with a known ABO and RhD blood group, to determine the influence of common blood groups on virus susceptibility. Distribution of blood groups was compared with data from nontested individuals. Participants (29% of whom were male) included 473 654 individuals tested for SARS-CoV-2 using real-time polymerase chain reaction (7422 positive and 466 232 negative) and 2 204 742 nontested individuals, accounting for ∼38% of the total Danish population. Hospitalization and death from COVID-19, age, cardiovascular comorbidities, and job status were also collected for confirmed infected cases. ABO blood groups varied significantly between patients and the reference group, with only 38.41% (95% confidence interval [CI], 37.30-39.50) of the patients belonging to blood group O compared with 41.70% (95% CI, 41.60-41.80) in the controls, corresponding to a relative risk of 0.87 (95% CI, 0.83-0.91) for acquiring COVID-19. This study identifies ABO blood group as a risk factor for SARS-CoV-2 infection but not for hospitalization or death from COVID-19.

Introduction
Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has spread rapidly since its emergence in December 2019, causing a pandemic with 18 093 891 people infected globally (as of 3 August 2020). In severe cases, individuals develop a number of symptoms, including acute respiratory illness, collectively known as coronavirus disease 2019 (COVID-19). Development of COVID-19 is associated with age, sex, and comorbidities, such as cardiovascular diseases,1 although severe disease is not limited to these risk groups. Recent reports have suggested that ABO blood groups might play a role in the infection,2-6 with a lower than expected prevalence of blood group O individuals among patients. ABO blood groups are increasingly recognized to influence susceptibility to certain viruses, including SARS-CoV-17 and norovirus.8,9 Blood group A and B glycosyltransferases also affect glycosylation in a large number of cell types, including epithelial cells in the respiratory tract10 and shed viral particles.11,12 A, B, and AB individuals are also at increased risk for thrombosis and cardiovascular diseases,13 which are important comorbidities among hospitalized COVID-19 patients,14 possibly mediated by glycosylation of proteins involved in hemostasis.15 To obtain valid estimates of relative risk (RR), representativeness of the reference material is important. Although blood group frequencies and susceptibility for SARS-CoV-2 can vary substantially among ethnic groups, Denmark is a relatively ethnically homogenous society with free access to health care services. Here, we take of advantage of this, as well as the Danish centralized registries, to compare the blood groups of 473 654 individuals tested for SARS-CoV-2 and stratified for severity, measured as hospitalization or death from COVID-19.

Methods
Study design, variables, and oversight
A retrospective cohort analysis of all individuals with registered ABO and RhD blood groups in Denmark was performed. Data were extracted from electronic health records capturing all Danish patients, the Danish Microbiology Database, the Danish Civil Registration System, Danish Authorizations Register for health care workers, the Danish Patient Safety Authorization Register, and the Danish National Patient Register in a pseudo-anonymized form.16 Information concerning ABO and RhD blood groups, SARS-CoV-2 test results, and hospitalization and/or death from COVID-19 was collected, as well as demographic information (sex, age, authorization as health care personnel) and cardiovascular comorbidities. Death from COVID-19 was defined as death within 60 days following diagnosis. Cardiovascular comorbidities were defined by the 10th revision of the International Statistical Classification of Diseases and Related Health Problems codes for acute myocardial infarction (I-21), heart failure (I-50), and cerebral hemorrhage or infarction (I-60-64). Cases 60 years of age or older were grouped as “older.”

According to Danish law, studies based entirely on registry data do not require approval from an ethics review board.17 The study was registered at the University of Southern Denmark’s data inventory (record no. 10/960).

Study population
From 27 February 2020 to 30 July 2020, 841 327 individuals were tested by real-time polymerase chain reaction for SARS-CoV-2 infection in Denmark. Eligibility was determined by whether ABO and RhD blood group information was available, which was the case for 473 654 individuals (56%). A reference group with relevant blood group information from 2 204 742 nontested individuals was included (alive on 31 January 2020).

Supplemental Figure 1 outlines the testing strategy in Denmark during the spring of 2020, which is explained in detail by Pottegård et al.16 As a result of the strategy initially followed in Denmark, a large number of health care workers are among the tested individuals. Twenty-nine percent of this population was male, and 71% was female. The majority of patients (74%) in this study had mild disease and were not hospitalized.

Study outcomes
The primary outcome was status of ABO and RhD blood groups and test results for SARS-CoV-2. Secondary outcomes were hospitalization and death from COVID-19.

Results
Of 841 327 people tested for SARS-CoV-2 in Denmark, ABO and RhD blood groups could be identified for 473 654 individuals (supplemental Figure 2). ABO and RhD data from 2 204 742 individuals not tested for SARS-CoV-2 were used as a reference, corresponding to ∼38% of the entire Danish population.

Supplemental Figure 3 shows the demographic characteristics of the tested population, stratified by sex and age. Of 473 654 individuals tested, 7422 were positive for SARS-CoV-2, and 466 232 were negative. In the population that tested negative for SARS-CoV-2, 32.0% were men, and the median age was 50 years (interquartile range, 36-64). Among positive cases, 32.9% were men, and the median age was 52 years (interquartile range, 40-67).

The distribution of ABO groups among those tested and the 2 204 742 nontested reference individuals is shown in Table 1. There was a slight, but statistically significant, difference in blood group distribution between the SARS-CoV-2− individuals and the reference population (P < .001). Among the SARS-CoV-2+ individuals, considerably fewer group O individuals were found (P < .001); conversely, more A, B, and AB individuals were noted (P < .001, P = .011, and P = .091, respectively). When blood group O was excluded, no significant difference was seen among A, B, and AB (P = .30). No difference in the RhD group was found between positively tested cases and the reference population (P = .15). We classified individuals after risk factors associated with COVID-19, including age ≥60 years, cardiovascular comorbidity, and job in the health care sector. No difference in the distribution of ABO groups was found when infected individuals with a given risk factor were compared with those without (all P > .1; supplemental Table 1). Together, these data indicate that the RRs for contracting SARS-CoV-2 are 0.87 (95% CI, 0.83-0.91), 1.09 (95% CI, 1.04-1.14), 1.06 (95% CI, 0.99-1.14), and 1.15 (95% CI, 1.03-1.27) for O, A, B, and AB individuals, respectively.

Table 1.
Distribution of ABO blood groups among individuals tested and not tested for SARS-CoV-2 in Denmark

Blood group SARS-CoV-2 tested, n (%) Reference population, n (%) P, SARS-CoV-2+ vs reference population RR (95% CI), positive individuals vs reference population
Positive Negative
O 2851 (38.41) 193 401 (41.48) 919 303 (41.69) <.001 0.87 (0.82-0.91)
A 3296 (44.41) 199 211 (42.73) 934 421 (42.39) <.001 1.09 (1.02-1.13)
B 897 (12.09) 52 838 (11.33) 252 559 (11.46) .091 1.06 (1.03-1.19)
AB 378 (5.09) 20 782 (4.46) 98 459 (4.47) .011 1.15 (1.05-1.31)
Total, n 7422 466 232 2 204 742
There was no difference (all P > .40) between ABO blood groups and clinical severity of COVID-19 for nonhospitalized patients vs hospitalized patients or for deceased patients vs living patients (Table 2).

Table 2.
Distribution of ABO blood groups and clinical severity among individuals infected with SARS-CoV-2 in Denmark

Blood group Confirmed SARS-CoV-2 infected, n (%) P, hospitalized vs nonhospitalized P, deceased vs alive
Hospitalized Nonhospitalized Deceased Alive
O 721 (36.96) 2130 (38.93) 201 (36.55) 2650 (38.56) .12 .35
A 896 (45.93) 2400 (43.87) 259 (47.09) 3037 (44.19) .12 .19
B 233 (11.94) 664 (12.14) 64 (11.64) 833 (12.12) .82 .74
AB 101 (5.18) 277 (5.06) 26 (4.73) 352 (5.12) .84 .68
Total, n 1951 5471 550 6872
7422 7422

Immigrants from nonwestern countries and their first-generation descendants are overrepresented among Danish COVID-19 patients (constituting 18% of cases but only 9% of the population),18 which could confound the ABO distribution among SARS-CoV-2+ individuals. Therefore, we performed a sensitivity analysis by calculating a weighted reference ABO distribution, taking into account the number of COVID-19 cases among immigrants from the nations constituting the largest sources of nonwestern immigration in Denmark (Pakistan, Morocco, Somalia, Turkey, and Iraq) and reference ABO distributions in their respective country of origin. Using this weighted ABO distribution as an alternative reference population, we reanalyzed and found an adjusted RR for blood group O individuals of 0.88 (supplemental Table 2), which was very similar to our initial result (RR, 0.87; Table 1).

Discussion
Here, we demonstrate that blood group O is significantly associated with reduced susceptibility to SARS-CoV-2 infection. Additionally, ABO blood groups were not associated with rates of hospitalization or death following infection.

Our study has several limitations. ABO blood group information was only available for 62% of all tested individuals, and only doctors and nurses were identified as health care personnel. The sex of the tested population was skewed, with females accounting for 71% of those who screened negative and 67% of those who screened positive. However, blood groups are generally independent of sex. More importantly, however, is the fact that blood group distributions vary among ethnic subgroups with different susceptibility for infection. Indeed, a higher than expected contribution of immigrants from nonwestern countries is noted among Danish COVID-19 patients,18 but a sensitivity analysis indicated this is not a major bias and, thus, is unlikely to affect the overall conclusion.

The data presented here are consistent with other studies reporting primarily on hospitalized patients2-6 and those exploring SARS-CoV-1 susceptibility.7 Several hypotheses could explain these results. In vitro studies have indicated that SARS-CoV-1 particles can be glycosylated by the A variant of the ABO glycosyltransferases, allowing anti-A antibodies to neutralize the virus.11 Although not studied, it is likely to be the case for the B variant, as well, and, therefore, for anti-B antibodies. Because anti-A and anti-B are present on mucosal surfaces in some individuals lacking the corresponding ABO blood group,19 this might explain the relative protection of blood group O individuals. In this context, it is interesting that the highest RR for infection was found for blood group AB lacking both antibodies. However, the RR of group AB did not differ significantly from that of group A or B; because of the paucity of blood group AB, it would require a considerably larger number of patients to clarify this. Alternatively, the effect could be indirect, as a result of the association between ABO blood groups and levels of von Willebrand factor, which is higher in non-O individuals15 and who are also more prone to arterial and venous thrombosis,20 which are important comorbidities for COVID-19. Importantly, the majority of patients reported here were not hospitalized and, therefore, were less likely to have such comorbidities.

Our findings of similar relative protection by blood group O in young individuals, in health care personnel, and in individuals without a registered cardiovascular diagnosis suggest that associations between non-O blood groups and comorbidities do not explain the apparent protection enjoyed by group O individuals, in line with findings reported by Zietz and Tatonetti.3 Moreover, our data do not indicate an association between blood group and progression to hospitalization or death from COVID-19. This is consistent with data from Ellinghaus et al,6 who did not find any differences in the usage of oxygen or ventilation between ABO blood groups in hospitalized patients. Given the known increased risk of thrombosis in non-O individuals and the evolving central role for thrombosis in the pathogenesis of COVID-19, it is important to explore this aspect more closely in larger patient cohorts (eg, by examining ABO blood type and viral load, the severity of symptoms, and the long-term effects following COVID-19). Furthermore, it should be emphasized that the 2 hypotheses do not exclude each other.

Last Edit: Oct 16, 2020 1:33:13 GMT by Admin

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COVID-19 Susceptibility By Race, Blood Type Nov 29, 2020 4:42:35 GMT

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Post by Admin on Nov 29, 2020 4:42:35 GMT

The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.

Certain blood groups less likely to get COVID-19

A large study adds to evidence that people with type O or Rhâˆ’negative blood may be at slightly lower risk from the new coronavirus. Among 225,556 Canadians who were tested for the virus, the risk for a COVID-19 diagnosis was 12% lower and the risk for severe COVID-19 or death was 13% lower in people with blood group O versus those with A, AB, or B, researchers reported on Tuesday in Annals of Internal Medicine. People in any blood group who were Rh-negative were also somewhat protected, especially if they had O-negative blood. People in these blood type groups may have developed antibodies that can recognize some aspect of the new virus, coauthor Dr. Joel Ray of St. Michael's Hospital in Toronto told Reuters. "Our next study will specifically look at such antibodies, and whether they explain the protective effect," Ray said. Whether or how this information might influence COVID-19 prevention or treatment is still unclear. (https://bit.ly/2JhQvws)

Vitamin D fails to help in severe COVID-19 cases

Low levels of vitamin D have been linked to higher risk for severe COVID-19, but high vitamin D levels do not fix the problem. Increasing vitamin D levels in critically ill patients did not shorten their hospital stay or lower their odds of being moved to intensive care, needing mechanical ventilation, or dying, doctors in Brazil found. They randomly gave 240 patients hospitalized with severe COVID-19 either a single high dose of vitamin D3 or a placebo. Only 6.7% of patients in the vitamin D group had "deficient" levels of the nutrient, compared to 51.5% of patients in the placebo group, but there was no difference in the outcomes, according to a paper posted on medRxiv ahead of peer review. The same was true when the researchers focused on the 116 patients with vitamin D deficiency before the treatment. The authors say theirs is the first randomized trial of its kind to show that vitamin D supplementation "is ineffective to improve hospital length of stay or any other clinical outcomes among hospitalized patients with severe COVID-19." (https://bit.ly/3mfqOeH)

Last Edit: Nov 29, 2020 4:43:31 GMT by Admin

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COVID-19 Susceptibility By Race, Blood Type Nov 30, 2020 21:00:07 GMT

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Post by Admin on Nov 30, 2020 21:00:07 GMT

Association Between ABO and Rh Blood Groups and SARS-CoV-2 Infection or Severe COVID-19 IllnessFREE
A Population-Based Cohort Study

Joel G. Ray, MD, MScMichael J. Schull, MD, MScMarian J. Vermeulen, MScAlison L. Park, MSc

doi.org/10.7326/M20-4511

Abstract
Background:
The ABO and rhesus (Rh) blood groups may influence risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

Objective:
To determine whether ABO and Rh blood groups are associated with risk for SARS-CoV-2 infection and severe coronavirus disease 2019 (COVID-19) illness.

Design:
Population-based cohort study.

Setting:
Ontario, Canada.

Patients:
All adults and children who had ABO blood group assessed between January 2007 and December 2019 and who subsequently had SARS-CoV-2 testing between 15 January and 30 June 2020.

Measurements:
The main study outcome was SARS-CoV-2 infection, determined by viral RNA polymerase chain reaction testing. A second outcome was severe COVID-19 illness or death. Adjusted relative risks (aRRs) and absolute risk differences (ARDs) were adjusted for demographic characteristics and comorbidities.

Results:
A total of 225 556 persons were included, with a mean age of 54 years. The aRR of SARS-CoV-2 infection for O blood group versus A, AB, and B blood groups together was 0.88 (95% CI, 0.84 to 0.92; ARD, −3.9 per 1000 [CI, −5.4 to −2.5]). Rhesus-negative (Rh−) blood type was protective against SARS-CoV-2 infection (aRR, 0.79 [CI, 0.73 to 0.85]; ARD, −6.8 per 1000 [CI, −8.9 to −4.7]), especially for those who were O-negative (O−) (aRR, 0.74 [CI, 0.66 to 0.83]; ARD, −8.2 per 1000 [CI, −10.8 to −5.3]). There was also a lower risk for severe COVID-19 illness or death associated with type O blood group versus all others (aRR, 0.87 [CI, 0.78 to 0.97]; ARD, −0.8 per 1000 [CI, −1.4 to −0.2]) and with Rh− versus Rh-positive (aRR, 0.82 [CI, 0.68 to 0.96]; ARD, −1.1 per 1000 [CI, −2.0 to −0.2]).

Limitation:
Persons who rapidly died of severe COVID-19 illness may not have had SARS-CoV-2 testing.

Conclusion:
The O and Rh− blood groups may be associated with a slightly lower risk for SARS-CoV-2 infection and severe COVID-19 illness.

Primary Funding Source:
Ontario Academic Health Sciences Centre AFP Innovation Fund and the Ontario Ministry of Health and Long-Term Care.

Type O blood may protect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (1–3). Non–peer-reviewed data from New York City suggest that rhesus-negative (Rh−) status may also be protective (4). Prior studies did not distinguish between SARS-CoV-2 infection and severe coronavirus disease 2019 (COVID-19)–related illness, were not done at a population level within a universal health care environment, comprised few patients typically recruited within a single hospital setting (5, 6), and were prone to ascertainment bias. These studies did not use appropriate control participants, such as those who had also undergone SARS-CoV-2 testing, and typically did not consider important confounders, especially preexisting comorbidities.

The uncertainty around ABO or Rh blood groups and SARS-CoV-2 infection persists (7). Accordingly, this population-based study was done to evaluate SARS-CoV-2 infection and severe COVID-19 illness in relation to ABO and Rh status.

Last Edit: Nov 30, 2020 21:00:51 GMT by Admin