Lengthy Screening Process

Lengthy Screening Process

Some donors wonder why Canadian Blood Services performs a lengthy screening process when it also tests their donations in the laboratory. Canadian Blood Services does test every donation using sophisticated, reliable procedures. However, while these tests are highly effective, they are not perfect. There are brief periods after infection, known as the window-period, during which current tests cannot detect signs of a virus. Advances in testing technology have reduced but not eliminated these window periods.

The minimum period between whole blood donations is 56 days. For many donors, that time can be much longer. Regulations require Canadian Blood Services to treat every donation as a separate event.

Some people have suggested that screening personnel ask the full set of questions to new donors only. Giving blood would then be faster for repeat donors, who might only be asked if anything changed since their last donation.

This would be dangerous. Answering the questions takes time because they are so detailed. Well-meaning blood donors could easily forget some seemingly insignificant detail. If that detail happened to be a risk factor, abbreviating the screening process could have disastrous consequences.

The donor screening process does take time. But a few minutes of caution is far better than a lifetime of regret.