Preventing Transfusion-Transmissible Infections in Kenya: Steps to Increase the Supply of Screened Blood

Public hospitals collect an additional 20,000 units, but may not screen all of them completely. Screening all of the blood collected is an immediate priority, as blood donors at hospitals may have higher levels of transfusion-transmissible infections. Based on norms set by the World Health Organization, Kenya may need to collect and screen a total of 410,700 units per year. To meet this goal, the country needs to consider cost-efficient choices for expanding the total supply of screened blood. Research questions include the costs and benefits of screening the entire current supply of blood for transfusions, and the most cost-efficient way to increase the total supply of screened blood. Ensuring a screened supply of blood for transfusion is an essential component of preventing HIV and other transfusion-transmissible infections (TTIs) such as syphilis, hepatitis B, and hepatitis C. The total volume of screened blood in Kenya is not known precisely, but the National Blood Transfusion Service (NBTS) currently collects and screens about 135,000 units from voluntary blood donors. Approximately 20,000 additional units per year are collected by public hospitals from family replacement donors. Where the blood comes from makes a difference. Family replacement donors are three times as likely to be infected with HIV as voluntary donors and twice as likely to be infected with herpes simplex virus type 2, a surrogate marker for sexually transmitted infections. Such findings parallel those from other studies in Africa. Over time, voluntary blood donors have become the major source for blood transfusion in Kenya, in contrast to the rest of sub-Saharan Africa. Kenya faces two steps in expanding the total supply of screened blood: (1) make investments to fully screen the current blood supply, especially the blood collected from family replacement donors, and (2) invest in increasing the total volume of collected and screened blood per year. The World Health Organization suggests collecting and screening 10 units per 1,000 citizens, which implies 410,700 units per year. This is 255,700 units more than what is collected now. Staff of the Health Policy Project consulted stakeholders in NBTS to define research questions. Cost data from a recent study on the NBTS were used. Data on the levels of TTIs among voluntary blood donors were available from NBTS for 2006-11. Comparable recent data for family replacement donors in Kenya were not available for any TTIs except HIV; thus, information from various East African studies was combined to compute factors, which help yield the likely levels among these donors. Fully screening the current blood supply is a priority, as it represents a good investment and will help in further reducing TTIs. The additional costs for hospitals to achieve 100 percent screening were calculated and compared to the averted costs of treating TTIs as a result of transfusing units of unscreened blood. The results suggest that a complete screening of blood already collected from family replacement donors represents a good investment and will help in further reducing TTIs. Increasing the volume of screened blood is also necessary to meet the gap of 255,700 units. The gap could be met by scaling up production through NBTS, through hospital-based collection and screening, or through a mix of both. The unit cost comparison between NBTS and hospitals shows that processing 255,700 extra units via NBTS would cost $17 million per year, while via the hospitals, the cost would be $8.4 million.