Because blood is collected from almost all newborn babies in the UK, newborn blood spot cards are particularly useful for monitoring the health of the whole population. They are also very useful for research into the health of mothers and babies.
Stored blood spot cards are used in the following ways:
To monitor and improve the newborn screening programme
Newborn screening laboratories use stored blood spot cards to monitor and improve the screening programme. They may use the blood spots to double-check the screening tests. For example, from time to time they may retest a number of spots to check that the screening tests are working properly. The laboratory may also use stored blood spots to develop and check new methods of testing.
To directly benefit families
Babies' stored cards may be used to directly benefit families. If a baby has died but the cause is unclear, a doctor may request that the baby's stored blood spots are tested to try to find the cause of death. Stored blood spot cards have been used, for example, to find out whether a baby had a genetic condition that may have caused their death.
In some cases, testing stored blood spots may also provide information about the parents' risk of having another baby with that condition. Sometimes this sort of testing also leads to tests being offered to other family members to find out if they have the same condition.
Stored blood spot cards might also be used to identify the body of someone who has been killed in a disaster. For example, stored blood spots have been used in other countries to identify the bodies of people killed in a factory fire and those killed by the tsunami in 2004.
To monitor the health of the general population
Blood spot cards can be used to:
• answer questions about the health of the general population
• provide information for health service planning
• help measure how well public health policies prevent or manage disease
It's sometimes possible to find out information about a mother's health from their babies' blood spots. For example, by testing a baby's dried blood spot, you can tell whether or not the baby's mother has HIV.
Anonymous blood spots (where the blood spots have been separated from any identifying information on the card) were used over a period of about 20 years from the late 1980s to measure the extent of HIV infection in the general population.
One study tested newborn blood spots and compared the numbers with diagnosed cases of HIV in pregnant women. It found that although the number of infected women was steadily increasing, most did not know they had HIV.
This led to a national policy to recommend voluntary antenatal HIV testing to all pregnant women. HIV detection rates are now very high, and the use of anonymised blood spots in this way has drawn to a close.
The blood spot cards have also been used for research to find out how many people have particular genetic conditions. This is valuable information to help plan healthcare services. For example, in some countries the spots have been used to find out how many people carry genetic mutations that cause an inherited condition called primary haemochromatosis.
To answer questions about specific health problems
Researchers can use stored blood spots to answer research questions about specific health problems. For example, researchers have tested the spots of children who have developed leukaemia later in childhood to see if the genes that might cause it were present when these children were a week old.
To develop new equipment and tests
Blood spots are needed when developing new screening equipment and tests. For example, stored spots have been used to test something called a tandem mass spectrometer. With this, it's possible to screen for many more conditions than was possible in the past. The blood spots have also been used in research to decide whether or not a screening programme should be introduced for other conditions, such as toxoplasmosis.
For police forensic work
In certain situations the police can apply for access to the blood spot cards of dead or missing individuals for forensic purposes. This happens very rarely. Current guidance is that samples from specific individuals who are alive and not missing can only be released with a court order.
The police are only allowed to apply for a court order to access blood spots for specific named persons. They do not have access to information from stored blood spot collections, and are not allowed to "trawl" through a collection of blood spots in the hope of identifying someone.
How are the interests of the public protected?
There are a number of ways in which the interests of the public and personal information are protected:
- regulations and laws governing the storage and use of blood spot cards – strict guidance exists about who is allowed to access these blood spot cards and how the cards can be used.
- code of practice – the NHS Newborn Blood Spot Screening Programme has developed a code of practice to govern the storage and use of newborn blood spot cards. Under the code of practice, it's recommended that the cards are stored for at least five years, and they may be stored for longer. Laboratory directors are "custodians" of the cards, storing them and ensuring guidelines are followed. The programme is currently reviewing the code of practice.
- laws – laws covering the use of the cards include the Data Protection Act 1998, the Health and Social Care Act 2001, and the Human Tissue Act 2004. Guidance on the management of blood spot cards has been developed with careful reference to these laws.
- ethical approval and scientific peer review – stored blood spot cards can only be used in research if the research is approved by a medical research ethics committee. All potential research projects must also be reviewed by other scientists. These scientists judge the scientific value of the research before a project can be approved. This process is known as "scientific peer review".
- parental consent – when parents are offered newborn blood spot screening for their baby, they are given a pre-screening leaflet and have a discussion with their midwife. This is to help them make an informed choice. Parents are also asked to consent to screening.
- anonymity and confidentiality – steps are taken to keep private any personal information contained in, or linked in any way to, the blood spot card collection. Where blood spot cards are used anonymously, identifying information is separated from the spots before they are tested.
When identifiable blood spots are used for research that parents or patients have given their consent to, steps are taken to protect patient confidentiality. When the newborn blood spots are collected, parents can choose whether or not they want to receive invitations to take part in this type of research in future.