Last Updated on Sep 23, 2020

Blood Groups

Human blood is categorized into two main groups-The ABO group and the Rh group.

HIV Antibodies

For all intents and purposes, Blood in humans is categorized into 4 subgroups – A, B, O and AB. Each of these groups may be Rh positive or Rh negative depending on the presence or absence of the Rhesus factor, which is believed to have come from the Rhesus monkeys.For example there may be individuals who may be A+ve or A-ve depending on the Rhesus factor. This applies to B, AB and O groups too. Some other categorization such as the MN blood groups are also recognized. These blood groupings are very handy when it comes to decisions regarding blood transfusions.

O group individuals are called ‘Universal Donors’ and AB group called ‘Universal recipients’. But this rule is applied only in extremely trying circumstances. It is always wise to transfuse an individual with blood from the same group blood.

Blood Groups

For all practical and routine purposes, it is ideal to transfuse to the patient the same group of blood which he belongs to. It is only under very dire emergency that we take O group as universal donor and AB groups as universal recipient. A group individuals have anti-B antibodies while B group people have anti-A antibodies. O, A and B group individuals must always be transfused with the same blood group.

Rh negative patient cannot receive blood from a positive individual. Any change in transfusion will result in antigen-antibody reactions which will lead to serious consequences.


  1. Donors who give blood voluntarily and for altruistic reasons have the lowest prevalence of HIV, hepatitis viruses and other blood-borne infections, as compared to people who donate for family members or in lieu of payment.
  2. WHO Fact sheet N°279, June 2008, Blood safety and donation


Shazidamain Friday, June 14, 2013

According to a recent survey conducted by World Health Organisation, 52.42% of all blood donated in India is through voluntary blood donation camps. The figure was 45% in 2002. This shows that nearly 47.58% of all blood donated is either from paid donors or from family members.

sriharsha.d Wednesday, April 24, 2013

i have donated my blood on 22 feb 2013. can i donate it again on 24 april 2013? i'm of 19 years

purnima.rajput Monday, April 22, 2013

kya jb koi physical ho to last night kya woh blood de sakta hai.....

Michael48 Wednesday, January 23, 2013

Can I donate at a childrens' hospital if i am taking balsalazide disodium fo colitis?

Dominik Tuesday, December 11, 2012

Can I donate blood if a smoked weed ?

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