Tick-Borne Infections Infiltrate U.S. Blood Supply

By Maryn McKenna
September 6, 2011

Excerpt:
In a paper released ahead-of-print by the Annals of Internal Medicine, researchers from the Centers for Disease Control and Prevention, Rhode Island and New York State report that 159 cases of babesiosis were caused by transfusions in the past 30 years and “the risk may be increasing.” Twenty-seven of the patients died..

Here are the details of their analysis. Between 1979 and 2009:

•There were 159 known cases of babesiosis caused by transfusions (and 3 more caused by a related organism, for 162 total)
•Infected donors were tracked down for 136 of those cases
•30 of the cases were caused by 12 donors, because donated blood is split into multiple products
•All but 4 of the cases were linked to receiving red blood cells (the remaining 4 involved platelets)
•77 percent of the cases occurred in the last 10 years, suggesting the risk is increasing
•Cases occurred in all 4 seasons of the year, though tick bites are seasonal
•Cases occurred in 19 states, but 87 percent of them were in the 7 states where Babesia is considered to be endemic — which the authors say may represent higher risk, or perhaps just greater awareness. the rest