VOLUME 37, ISSUE 1

Pre-donation screening plays a crucial role in ensuring the safety of the donated blood supply through systematic monitoring and prevention of adverse events related to blood donation and transfusion. Blood screening protocols are essential for identifying risk factors that could jeopardize the safety and quality of donated blood. The donor screening process includes three critical aspects: the pre-donation questionnaire, the medication deferral list, and recent travel considerations. These three sections address the significance in maintaining a safe blood supply and highlight the crucial precautions that help minimize risks within blood donation and transfusion.

1. Pre-Donation Questionnaire

The pre-donation questionnaire is the foundation of the donor screening process in blood banking. It is designed to evaluate the donor’s eligibility based on their past medical history, lifestyle, and potential risk factors. The goal is to exclude potential donors who may be at increased risk of transmitting infectious disease through blood donation.

The questionnaire covers a wide range of topics, including the donor’s medical history, past surgeries, transfusions, and immunization history. Donors are asked about chronic diseases such as HIV, hepatitis, or other bloodborne pathogens. Lifestyle questions regarding sexual practices, intravenous drug use, and other high-risk behaviors are included to minimize the likelihood of disease transmission.

The questionnaire also includes questions about recent health issues, such as infections, fevers, or unexplained weight loss, which could be a harbinger of underlying pathology. If any concerning responses are identified, the donor’s eligibility for blood product donation may be deferred, either temporarily or permanently. This detailed self-assessment is crucial for maintaining the integrity of the blood supply and protecting recipients from potential harm.

While the pre-donation questionnaire is highly effective in identifying at-risk donors, it is reliant on the donor’s honesty and self-awareness. Inaccurate or incomplete information can compromise the safety of donated blood. Therefore, it is essential to continually refine the questionnaire based on emerging data and to ensure that donors understand the importance of truthful responses.  It is believed that the stigma of honestly revealing underlying diseases or risky behaviors may be the reason that targeted donations from family members may carry an increased risk of transmission of disease when compared to transfusions from the general pool of blood products.

2. Medication Deferral List

Certain medications can pose risks to blood recipients, requiring either temporary or permanent deferral of donors who use these drugs.  Anticoagulants (e.g., warfarin, apixaban) and antiplatelet medications (e.g., aspirin, clopidogrel) can interfere with the clotting process in the transfusion recipients and patients taking these medicines are therefore excluded from the donor pool. Certain immunosuppressants can compromise immune function in blood recipients. Donors on these medications are often deferred for a period of time after discontinuing the drug to ensure the drug effects have worn off. Teratogenic medications like isotretinoin (used to treat acne) and certain types of cancer therapies may also require deferral from donation due to their potential for teratogenic or cytotoxic effects on recipients.

Temporary deferral is often applied for antibiotics and is often dependent upon the type and severity of the infection being treated. The medication deferral list is regularly updated based on new research and changes in medical practice to ensure the most up-to-date safety measures.

The medication deferral process must balance the need for a safe blood supply while also retaining donors. Clear communication about the reasons for deferral, along with guidance on when the donor can return helps prevent discouraging potential long-term donors. Blood centers also need to continually update and educate staff about changes to the deferral list, ensuring that deferrals are applied consistently and appropriately.

3. Recent Travel

Geographic restrictions are necessary to protect the blood supply from transfusion-transmissible infections such as malaria, Zika virus, dengue, and Chagas disease, among others.

Donors who have recently traveled to areas where certain diseases are endemic are deferred for a specific period depending on the disease and its incubation period. For example, donors returning from malaria-endemic regions like much of Africa and South America may be deferred for up to 12 months to ensure they have not contracted the infection, as asymptomatic carriers can still transmit the parasite through blood transfusion.

Emerging global health threats, such as the Zika virus, require blood banks to continually monitor travel advisories issued by health authorities like the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). Travel to regions affected by outbreaks or epidemics may lead to temporary suspension of donations from individuals returning from those areas.

In recent years, technological advances such as pathogen reduction techniques and nucleic acid testing (NAT) have improved the detection of bloodborne pathogens in donations. However, even with these advancements, screening for recent travel history remains crucial. The global nature of infectious disease spread means that travel-based deferrals need to be adaptable and responsive to a constantly shifting epidemiologic landscape.

Conclusion

Pre-donation screening is vital in ensuring the safety of the blood supply.  Effective screening measures, including the pre-donation questionnaire, medication deferral list and recent travel history, are essential in minimizing risks to transfusion recipients. Continuous improvements in screening processes, along with advancements in diagnostic technology, ensure that blood donations remain safe and reliable. By maintaining thorough screening and deferral practices, blood banks can protect the health of both donors and recipients while responding to emerging threats in transfusion medicine.