If a person carries a blood group A resists disease, more than the person that carries a blood group B carries.
A blood type (also called a blood group) is a classification of blood based on the presence and absence of antibodies and also based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs). These antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system. Some of these antigens are also present on the surface of other types of cells of various tissues. Several of these red blood cell surface antigens can stem from one allele (or an alternative version of a gene) and collectively form a blood group system. Blood types are inherited and represent contributions from both parents. A total of 35 human blood group systems are now recognized by the International Society of Blood Transfusion (ISBT). The two most important ones are ABO and the RhD antigen; they determine someone's blood type (A, B, AB and O, with +, − or Null denoting RhD status).
Thank so much dear Dr. Shibabrata Pattanayak But in our daily life we see the spread of immune weakness and viral diseases in people with a particular blood group !?
Blood types help us to fight diseases and tell us what major disease epidemics a given population suffered in its recent history, (e.g. in the last thousand years). For example, most native Americans belong to group O. It is believed that this is due to a syphilis epidemic and that the O type were better at fighting off the disease. Group A and B make people more resistant to cholera, while AB confers the most resistance. O offers virtually no immunity against cholera. B confers weaker protection against plague. This is probably why B is more common in North-East Europe, which was virtually unaffected by the Black Death during the Middle Ages.
A-type carriers are the most likely to survive plague, but suffer from a higher rate of heart disease, because their blood is more likely to clot. They are also at increased risk of contracting smallpox and developing cancer of the esophagus, pancreas, and stomach. Type O, contrarily to A, is slightly protective against cardiovascular problems. It also boosts resistance against tuberculosis, but increases the risk of venous thromboembolism and developing duodenal and peptic ulcers. It also attracts more mosquitoes (through which malaria is transmitted). A recent study revealed that people with type O blood are less likely to get pancreatic cancer, but also stomach, breast, ovarian and cervical cancer.
The ABO blood group system isn't the only antigen system found in humans. There are about 30 human blood type systems: Rhesus, Kell, Diego, Duffy, Kidd, and so on. Each have a role in immunity. Some are found only in some specific populations and completely absent elsewhere. This is the case of Diego antigens, found only (at low frequency) among Mongolic people and Amerindians.
An interesting issue requiring scientific investigation. If the factors differentiating particular blood groups are the issues of the presence or absence of specific antibodies and antigens, it is possible differences in resistance to specific diseases caused primarily by external factors that can be combated by these antibodies or identified by these antigens.
My question on investigative research is if the blood group of the patient has a direct effect on the effectiveness of the coronavirus infection. Does 0 Type patients better respond to the treatments?
I cannot find much statistics on the positive patients/negative swab testing blood group of the tested for the time being.
Risk of heart disease and blood clotting conditions Some researchers believe that people with types A, B and AB blood have an increased risk of coronary heart disease, due to increased levels of inflammatory markers and certain proteins in the blood that lead to blood clotting. That translates into an increased risk of venous thromboembolisms, which are blood clots that start in veins (as opposed to arteries). Estimates vary, but the most recent and rigorous studies put the risk at about double.
Heart attacks and stroke are also clotting problems. If a clot blocks blood flow to the heart, that’s a heart attack; if it blocks blood flow to the brain, it’s a stroke. People with blood type A have a 24 percent higher risk of heart attack than people than people with AB or O blood types. For stroke, people with type AB blood have an 83 percent higher risk.
Anti-A antibodies specifically inhibited the adhesion of SARS-CoV S protein-expressing cells to ACE2-expressing cell lines. Given the nucleic acid sequence similarity and receptor angiotensin-converting enzyme 2 (ACE2) binding similarity between SARS-CoV and SARS-CoV-2, the lower susceptibility of blood group O and higher susceptibility of blood group A for COVID-19 could be linked to the presence of natural anti-blood group antibodies, particularly anti-A antibody, in the blood.
See the different reality in different sites. It needs extra time to make a conclusion.
COVID-19 and Blood Type
Study finds no relationship between blood type and severity of COVID-19
By MGH NEWS AND PUBLIC AFFAIRS, July 17, 2020 Research
HARVARD MEDICAL SCHOOL (https://hms.harvard.edu/news/covid-19-blood-type)
Blood type is not associated with a severe worsening of symptoms in people who have tested positive for COVID-19, report Harvard Medical School researchers based at Massachusetts General Hospital.
Their findings, published in the Annals of Hematology, dispel previous reports that suggested a correlation between certain blood types and COVID-19.
The study did find, however, that symptomatic individuals with blood types B and AB who were Rh positive were more likely to test positive for COVID-19, while those with blood type O were less likely to test positive.
Testing the association between blood type and COVID-19 infection, intubation, and death
Michael Zietz and Nicholas P. Tatonetti
Preprint Testing the association between blood type and COVID-19 infe...
A recent study of patients in China discovered an association between ABO blood type and SARS-CoV-2 infection status by comparing COVID-19 patients with the general population. Whether blood type is associated with increased COVID-19 morbidity or mortality remains unknown. We used observational healthcare data on 1559 individuals tested for SARS-CoV-2 (682 COV+) with known blood type in the New York Presbyterian (NYP) hospital system to assess the association between ABO+Rh blood type and SARS-CoV-2 infection status, intubation, and death. We found a higher proportion of blood group A and a lower proportion of blood group O among COV+ patients compared to COV−, though in both cases the result is significant only in Rh positive blood types. We show that the effect of blood type is not explained by risk factors we considered (age, sex, hypertension, diabetes mellitus, overweight status, and chronic cardiovascular and lung disorders).