Bloodborne HIV: Don't Get Stuck!

Additional information about blood transfusions

Unnecessary transfusions: Some studies in Africa estimate that half or more of patients given blood would have been better off without the transfusion. Many children and pregnant women with anemia, but not life-threatening anemia, receive unnecessary transfusions.

Testing transfused blood: All governments in Africa require that transfused blood be tested for HIV. Although most countries in Africa report that all or most blood is tested for HIV, WHO assessed in 2006 that less than 12% was “tested for HIV in a quality-assured manner.”[i]

Emergencies, remote areas: Fresh blood is required to treat blood disorders if blood products are not available. Similarly, in remote areas that have poor communication with blood banks, doctors may transfuse fresh blood. Because fresh blood must be used within 6 hours from the time it is taken from the donor, and because it may not go through a blood bank, it may not be tested according to the rules.

Not investigating HIV from blood transfusion: Blood banks are required to maintain records on all blood that is collected and transfused. Although tens of thousands of people in Africa live with HIV infections attributed to blood transfusions, this is usually suspected and not tested. Except for South Africa, no African government routinely traces and re-tests donors when people who receive transfusions are later found to be HIV-positive. Tracing allows a check on blood bank management as well as on test accuracy. It might also determine that the transfused blood did not cause the infection, so that another blood or sexual exposure would have to be considered.

Outside South Africa, tracing and retesting donors has often been blocked by government policy not to tell donors their HIV status. For example, in Uganda, when a donor’s blood tests HIV-positive, the policy for many years has been to dispose of the blood, but not to tell the donor his or her HIV status.

“Window period”: Most blood tests look for antibodies to HIV, which are chemicals that people with HIV infections make to fight HIV. When someone has a new infection, it takes weeks for the body to make antibodies that show up on an HIV test. This is the “window period” – when blood tests won’t find antibodies, although blood carries HIV.

Although there has been a lot of discussion about the window period, it is less important than some other risks. You have more risk to get HIV due to management errors in the testing, labeling, and storage of blood.[ii] Moreover, transfusions come with risks that have nothing to do with HIV – including known but untested pathogens (such as the tuberculosis bacteria), unknown pathogens, mis-matching of donors and recipients, and other factors. Transfusions are dangerous – avoid them if you can.

Risk to get HIV from a transfusion

If the transfused blood comes from an HIV-positive donor, you are almost certain to get HIV. If the transfused blood has been tested for HIV, and if the provider uses a new disposable needle and tube to get the blood into your vein, you nevertheless have a small remaining risk to get HIV – due primarily to possible errors in testing and labelling blood.

Evidence that transfusions have infected people with HIV

Many studies in Africa find that people who have been transfused vs. people who have not been transfused are more likely to be HIV-positive. These risks vary from study to study, which is reasonable considering that blood programs are more thorough and safer in some places than in others.

As of 2005, WHO estimated that transfusions infect 160,000 people worldwide each year,[iii] accounting for 5% of new HIV infections. This is a weak estimate, calculated from estimates of the numbers of transfusions and the percentage of transfused blood that is contaminated. Because transfusions are not so common, and because countries with some of the worst HIV epidemics (especially South Africa) do a pretty good job screening transfused blood, 5% is likely an over-estimate of the proportion of HIV infections from transfusions.