Blood is vital to human life and across the world, millions of lives are saved through blood transfusions. However, the risk of receiving improperly tested blood is increasingly high even with ongoing efforts to screen donated blood.  Patients, especially those, who require transfusions regularly, are more at risk of getting infected with HIV or hepatitis B or hepatitis C if given blood that has not been collected and tested correctly.

Fortunately, there are newer technologies that help a great deal in minimising transfusion related infections. While some tests still target a body’s response to a virus, there are others which test directly for the viral presence. As such, it enables faster detection of infections.

Below are some commonly asked blood related questions. If you don’t find what you are looking for, please write to us at This email address is being protected from spambots. You need JavaScript enabled to view it. and we will be happy to help you.

 1.       Why is it important to screen (test) blood before transfusing it?

The simple answer is to prevent infections. Who would want to go to a hospital for surgery and come back with Hepatitis C?  In the past 20-25 years, there has been an increased prevalence of viruses like Human Immunodeficiency Virus [HIV], Hepatitis B and Hepatitis C. Sometimes, a donor is aware that he is infected but more often than not, he may not be, especially if he doesn’t show any symptoms of illness. If such blood is transfused to a patient, there is every chance he would get infected as well.

  2.     Which diseases can be transfused through blood?

 Blood transfusion continues to be a likely source of disease transmission. Bacteria, viruses, and parasites are all capable of being transmitted via transfusions. Common viral infections through blood are –

 - Human immunodeficiency virus (HIV)

 - Hepatitis viruses

 - West Nile virus (WNV)

 - Cytomegalovirus (CMV)

 - Human T-cell lymphotrophic viruses (HTLVs)

 - Parvovirus B19

  In India though, transfusion transmitted infections generally found are of HIV and Hepatitis B & C.

 3.       Who are at risk of transfusion transmitted infections?

At major risk are the patients who need multiple transfusions. Such groups may include thalassemics, cancer patients, haemophiliacs. But practically, anybody who requires a blood transfusion has some chance of being infected, especially if proper care is not taken during screening and transfusing. 

4.       What are the threats to safety of blood supply?

The greatest threat of blood transfusion is the transmission of infected blood which is undetected by conventional tests. Current licensed blood screening techniques enable blood banks to determine the exposure to blood-borne pathogens through the detection of virus-induced antibodies. These mandatory serologic tests like ELISA, detect the antibodies, but not the virus itself. Consequently, some transfusion recipients may unwittingly be exposed to serious disease if the blood products they receive contain the virus, but not the antibodies.

5.       What is the blood safety scenario in India?

The Govt of India mandates testing all donated blood for HIV, Hepatitis B, Hepatitis C, Syphillis and Malaria. Blood Banking is governed by the Drugs & Cosmetic Rule in India. According to this rule, only blood tested non reactive can be transfused to patients.

 - 1989 - HIV testing mandatory for blood banks.

 - 1999 - Hepatitis B surface antigen, Malaria and Syphilis testing made mandatory.

 - 2001 - Hepatitis C virus and test for antibody to Hepatitis C made mandatory.

6.       What is the current overview of blood banks and blood donations in India?

According to the Central Drugs Standard Control Organization (CDSCO), India has a total of 2535 licensed blood banks. Last year’s annual blood collection was approximately 8.2 million units but requirement was close to 10 million units leading to a shortage of 2 million blood units. 

The current donations are collected and screened in over 2,000 blood centers across India.Each blood center has its own standards and practices.The blood center facility varies from world-class laboratories within famous corporate and private hospitals to poorly equipped hospitals. The Indian blood transfusion service is very fragmented.The main issues include but are not limited to:

 - Lack of an effective blood authority

 - Lack of a strategic framework for developing a safe, reliable and efficient blood transfusion service

 - Lack of safe voluntary unpaid blood donors

 - Currently 70% of blood source is through replacement donations

 - 30% of blood sourced is from a mixture of paid and true voluntary donations

 - Quality of Screening Tests and Methods

 - Lack of quality reagents and test kits

 - Lack of adequate training for hospital staff

 - Poor laboratory procedures

 - Inadequate basic facilities within a majority of blood centres

7.       What is the structure of the Blood Transfusion Service in the country?

 Blood banks in India are categorized into different sectors:

- Government Blood Bank

- Private Blood Bank

- Voluntary/Charity Blood Bank

Though these blood banks have different practices and funding processes, all of them are regulated by Drug Control General of India (DCGI). The Ministry of Health and Family Welfare establishes blood safety related national policies with inputs from National AIDS Control Organization (NACO) and the National Blood Transfusion Council (NBTC). All major hospitals (government and private) have an in-house blood bank. 

8.       What are the common tests used for blood screening in India?

All licensed blood banks in India are required by law to test blood before transfusing to patients. However, there are limitations in the widely used serological tests (i.e. ELISA).Serological tests take time as they detect anti-bodies — the body’s response to avirus. Since these viral infections take time to manifest, accurate results may not be noted and infected blood is transfused as safe blood.

Mandatory tests for blood screening are:

- ELISA for HIV I/II Antibody

- ELISA for Hepatitis B (HBV) surface antigen

- ELISA for Antibody to Hepatitis C (HCV)

- VDRL/RPR for Syphilis

- Screening for Malarial Parasite

9.       Is there anything more advanced than serological tests for blood screening?

Yes, Individual Donor Nucleic Acid Testing (ID-NAT) is the latest technological advance in ensuring the safety of the nation’s blood supply. ID-NAT is a direct test which targets the viral DNA/RNA.

10.   What is the difference between ID-NAT and ELISA?

The main difference between ID-NAT and ELISA is the time taken to detect infection. Being a direct test, ID-NAT greatly reduces the ‘Window Period’ or the time between donor exposure to a virus and the presence of detectable amount of antibodies / antigens.

Direct test Indirect test
Targets viral DNA/RNA Targets antibodies – i.e. body’s response to virus
Can detect small amounts of virus in blood Doesn’t detect the virus, only the antibodies
Time taken for HIV-1  detection: 4.7 days Time taken for HIV-1  detection: 15 days
Time taken for HCV detection: 2.2 days Time taken for HCV detection: 58.3 days
Time taken for HBV  detection: 14.9 days Time taken for HBV detection: 38.3 days

11.   What are the benefits of ID-NAT?

- ID-NAT is the most sensitive and specific test for detecting HIV, HCV and HBV infections in blood. It has raised the bar in blood safety.

- ID-NAT complements serological screening by providing an additional layer of safety to Blood Supply, particularly in regions of high prevalence like India.

- ID-NAT prevents spread of HIV/AIDS and Hepatitis by significantly reducing the window period, resulting in fewer TTIs and safer blood.

- There are published cases where ELISA found the blood sample safe, but ID-NAT caught the infectious virus.

- ID-NAT not only prevents transfusion of window period infections but also detects occult infections (chronic cases where no antibodies are present and mutant viruses (where the virus has modified its structure)

- ID-NAT reduces risk of TTI’s among multi-transfused patients like Thalassemics and those with cancer.

- Improves confidence in the nation’s blood supply by detecting false negative serology results.

12.   Which countries use NAT?

Blood safety is a major concern all over the world, and most countries have added NAT as part of their routine blood screening protocols. NAT is used in Australia, Belgium, Brazil, Bulgaria, Caribbean, Czech Republic, Denmark, Egypt, Estonia, France, Germany, Greece, Hong Kong, Hungary, Indonesia, India, Israel, Ireland, Italy, Korea, Latvia, Lithuania, Malaysia, Mexico, Netherlands, New Zealand, Poland, Portugal, Romania, Singapore, Slovenia, Slovakia, South Africa, South Korea, Spain, Sweden, Switzerland, Thailand, Turkey, United Kingdom, United States.

13.   Is ID-NAT available in India?  

Indraprastha Apollo Hospital in New Delhi was the first in India to implement ID-NAT. Today, ID-NAT testing is well accepted in both Govt. Institutes, as well as in corporate hospitals. Prestigious institutes across the country have incorporated ID-NAT testing into their regular screening protocols. AIIMS, NTR Blood Bank,  AFTC, Medanta -The Medicity, P.D. Hinduja, CMC Vellore all offer ID-NAT tested blood. To see who else in India screens their blood units using ID-NAT, please click here 

14.  Why is it essential to make ID-NAT tested blood available to everyone?

It is the right of every citizen to get safe blood. This was reiterated in a Supreme Court judgment in 1999, where the Court directed the government to formulate a National Blood Policy and to ensure safe blood for all its citizens.

Patients in developing countries like India are more likely to receive blood that is contaminated with infectious diseases like HIV & Hepatitis, than industrialized nations because of Higher disease prevalence, Use of paid, family / replacement donors, Inadequate serology-based screening, Concealment of medical history and / or risky behavior. Also, in India, the social, clinical and economic effects of chronic infections / diseases like HIV, AIDS, Hepatitis B & C, and Cancer can be fatal.  Blood safety is absolutely essential to ensure that a patient who comes for treatment is not made sicker by another illness. With ID-NAT, Zero Risk Blood is now that much closer.

15.   How does ID-NAT benefit the patients?

Indraprastha Apollo Hospital, New Delhi conducted a Multicenter evaluation of Individual Donor Nucleic Acid Testing (ID-NAT) for simultaneous detection of Human Immunodeficiency Virus -1 & Hepatitis B & C viruses in Indian blood donors.

12,000 donations from 8 Indian blood centers were screened by ID-NAT. Results indicated that 1 in 1,528 tested negative by serological test but tested positive with ID-NAT. Based on the results of this study, it can be hypothesised that over 3200 TTIs can be prevented annually.

Apart from the multi centre study, there were others undertaken in India –

Site Name


# Sample

Yield [sero -ve but ID-NAT +ve

Yield rate

Multicenter Study Apollo

June 2004 - Jan 2005



1 in 1528

Apollo Delhi Routine

Apr 2006 - June 2007



1 in 3182


Nov 2008 - June 2009



1 in 1164

AIIMS Routine

Jul 2010 – Jan 2011



1 in 2622

AFTC Routine

Jan 2011- Jun 2011



1 in 218


Sunday the 23rd - . Powered by top online poker and Joomla!