While research results explaining the risk of infection or prognosis of the novel coronavirus infection (COVID-19, Corona 19) in association with a specific blood type have been continuously published, a research result that this time corona 19 is independent of blood type came out.
Joint researchers such as Intermountain Medical Center in Utah in the United States said in a paper published on the 5th of’The JAMA Network Open’, “No specific relationship was confirmed between Corona 19 and ABO blood types.” The connection was completely denied.
The researchers also pointed out that, as this study was the result of a large-scale survey of more than 100,000 people, the investigation of Corona 19 and blood type conducted without thorough control of genetic factors, geographic location, and virus type in the future is meaningless.
○ Researchers at Wuhan Central Hospital in China raise blood type association for the first time.
Since the Corona 19 epidemic last year, there have been several attempts to explain the severity or risk of infection of Corona 19 in relation to blood type. It started with Chinese researchers. Researchers at Huazhong University of Science and Technology, located in Wuhan, Hubei Province, China, conducted a blood type study on 265 patients who were hospitalized at Wuhan Central Hospital for Corona 19 from February 1 to March 25 last year, and found that 104 (39.3%) had type A. It was reported that the number of infections was the highest in the order of type O (68 persons·25.7%), type B (67 persons·25.3%), and type AB (26 persons·9.8%).
The researchers examined the blood type ratio using 3694 people who were not infected with Corona 19 as a control group in Wuhan City, with type O being the most at 1250 (33.8%), followed by type A (1188, 32.3%) and type B (920). 24.9%) followed by AB type (336 persons·9.15).
The researchers compared the corona 19 inpatient group and the control group at Wuhan Central Hospital, and found that type O was the lowest in cases of corona 19 infection by percentage. If it is not related to blood type, the proportion of each blood type should be similar in the corona19 patient group or in the control group, whereas type O accounted for 33.8% in the control group, while the difference was large, representing 25.7% in the patient group.
On the other hand, type A showed 32.3% of the control group, but it recorded 39.3%, which is the most common among corona19 infected people, showing a high corona19 positive rate. Accordingly, the researchers argued that type A has a relatively higher risk of corona 19 infection than type O.
Researchers in Italy and Spain have wedge on this claim. Researchers from the’COVID-19 Host Genetics Initiative’, launched by a group of 12 biobanks in the United States and Europe to find out the cause of Corona 19 at the genetic level, announced on October 15 last year in the medical journal New England. “The 3p21.31 gene cluster appears to be involved in the severity of Corona 19,” in the Journal of Medicin (NEJM). “In the case of ABO blood types involving the 9q34.2 gene cluster, the risk of Corona 19 compared to other blood types in the case of ABO Is high”.
At the same time, on October 14 last year, an international academic journal’Blood Advances’ published a paper by a Danish researcher saying that type O has a lower risk of corona 19 infection.
○ US researchers surveyed a cohort of 10,7796 people
However, studies have continued to show that there is no relationship between Corona 19 and blood type. Researchers at Massachusetts General Hospital in the U.S. conducted a survey of 7648 people who had been tested for Corona 19 from March 6 to April 16, 2020. It was announced in the’Hematology Newsletter’ on July 12 last year that it could not find any evidence of change.
Researchers at Columbia University’s Irving Medical Center also surveyed 11,112 patients with Corona 19 registered at hospitals in New York at Nature Communications on November 13 last year. , According to the results of a study, Corona 19 is not explained by only types A and O, such as the higher risk of death in AB type.
This time, researchers at Intermountain Medical Center analyzed the data of 10,7796 people who were diagnosed with Corona 19 for 8 months from March 3 to November 2 of last year. This is the first large-scale cohort study of more than 100,000 people. The researchers argued that data analysis did not find any association with specific blood types, such as increasing the severity of Corona 19 or lowering the risk of infection.
In particular, type A, which was designated as a blood type with a high risk of infection, had a 3% lower diagnostic test positive rate than type O, and 11% fewer hospitalized cases than type O after being tested positive. As the symptoms worsened, 16% of them were transferred to the intensive care unit.
In the paper, the researchers pointed out that “ABO blood types have different blood type ratios according to race and region, but previous studies did not take into account differences in genetic background, geography, and environment, while the sample size was small.”