Enligt den här svenska studien så har blodgrupp en påtaglig betydelse för mortalitet och behovet av vård på IVA. Människor med Bg A kan i princip definieras som en riskgrupp enligt studien.
"Coronavirus disease 2019 (COVID-19) is primarily associated with respiratory failure, but both renal and circulatory failure is common in patients that require critical care or die of the disease [1]. A recently published GWAS showed a strong association between severe COVID-19 and the ABO blood group locus in a cohort from Italy and Spain, with a higher risk for patients with blood group A [2]. This is consistent with data on susceptibility to COVID-19 being associated with blood group in Chinese [3]. Although the GWAS dataset did not include data on mortality, there is a preliminary report in an American cohort that blood group A is associated with both severity of COVID-19 and death [4].
Here, we present data on blood type distribution from a Swedish critical care cohort (n = 64) compared to the blood type distribution in the population as a whole: A 43%, AB 4%, B 9%, and O 44% giving a dichotomized distribution of A/AB 47% to B/O 53% [5]. Blood typing was performed using routine clinical procedures at the Clinical Immunology and Transfusion Medicine at the University Hospital in Uppsala.
Using the population blood type distribution to estimate the expected frequencies,
we found an association of blood type A with the risk of requiring critical care (HR (95% CI) = 2.01 (1.23–3.28)) and increased risk of death within 30 days (HR (95% CI) = 3.16 (1.28–7.77)) in COVID-19 (Fig. 1). This indicates that the findings in the previous studies are consistent also in a northern European population.
...
Taken together, with previously published data, this indicates that blood group A is a risk factor for disease severity and death in COVID-19 irrespective of the genetic background."
https://ccforum.biomedcentral.com/articles/10.1186/s13054-020-03223-8