Routine tests
All donations are tested for:
- HIV
- HTLV
- Hepatitis A
- Hepatitis B
- Hepatitis C
- Hepatitis E
- Syphilis
High levels of Human Parvovirus B19 (Slapped Cheek Syndrome) These infections can be passed on easily by blood transfusion, so testing is an important way to keep blood safe for patients.Our tests are very reliable, but there is an extremely small chance that we could miss an infection in its early stages. This is why we also screen our donors using the questions on the donor health check. By combining donor questions with state of the art testing we can keep our blood supply as safe as possible. A small sample of every donation is frozen and kept for at least five years. This is done in case we need to carry out additional tests at a later date.
The testing process
Samples from each donation are tested using an automated system. If everything is negative the donation can be released for use in patients. Occasionally a donation will cause a reaction during the automated testing process. If this happens, we send samples of the donation to our reference laboratory for more in-depth testing. This specialised testing will show whether the reaction is false or whether the donation carries one of the infections we test for. Approximately three in every 1,000 donations cause a reaction in our initial screening tests but only a very few of these turn out to be true infections. The majority are false reactions.
False reactions
On occasion, tests used by SNBTS (Scottish National Blood Transfusion Service) will produce false positive results. Because of our safety procedures, SNBTS cannot use a donation if it gives a false reaction. This is the case even if the donation has been cleared by our reference laboratory.
If a donor’s blood causes a false reaction we will write to let them know. The false reaction does not mean that there is anything wrong with their health. There is no need for the donor to see a doctor or have any additional tests. They will be able to donate again once the reaction has cleared. We will check this by taking samples, rather than a full donation, when they next attend a session.
Donors who test positive
Very rarely we find that a donor has evidence of a current or previous infection with one of the conditions listed earlier. In this situation, we will always inform the donor. We will get in contact with anyone with a positive test either in writing or by phone. Depending on the circumstances, we may seek further conversation. SNBTS clinical staff will give confidential advice to any donor who tests positive. They may also ask permission to refer the donor to an appropriate clinical service for further tests and follow up if required. If we are not able to contact a donor who has tested positive, we may discuss their case with an appropriate service such as their GP or a local sexual health clinic if requiring further follow-up.
Other tests: Malaria, West Nile virus, Chagas disease
We sometimes test donors or donations for these infections, depending on previous medical or travel history. More information can be found at scotblood.co.uk, or in our Travel information for blood donors leaflet.
Public health
We are required by law to notify Health Protection Scotland when we diagnose some infections, including Hepatitis A, Hepatitis B, Hepatitis C and Hepatitis E.
NATL 042 05
Published April 2024
Contact us
Telephone: 0345 90 90 999
Email: nss.snbtsenquiry@nhs.scot
Web: scotblood.co.uk
Facebook: givebloodforscotland
X: @givebloodscot
Instagram: givebloodscotland
This publication can be made available in large print, braille (English only), audio tape and different languages. Please contact nss.equalitydiversity@nhs.scot for further information.