Chagas' disease parasite found in desert blood samples
10:00 PM PDT on Friday, August 17, 2007
By PHIL PITCHFORD
A desert blood bank has found what it believes to be the second case in three months of a potentially fatal blood-borne parasite, which it says is further proof that blood centers should be testing for the disease.
The Inland region's largest blood bank, however, said it has no plans to begin testing for Chagas' disease because it believes there is insufficient evidence that the disease can actually be transmitted through blood products.
The debate involves two blood centers that compete for business from hospitals around the Inland region. At issue is whether the disease, which is prevalent in Central and South America, poses enough of a health risk here to justify the extra expense involved in testing donated blood.
Chagas' disease is caused by a parasite primarily spread by an insect that bites infected animals and people. As many as 11 million people in Latin America could have Chagas' disease but not know it, according to the U.S. Centers of Disease Control and Prevention. Without treatment, the disease can be fatal.
Chagas' disease rarely has been seen in the United States, but health officials are concerned that immigration from countries where occurrence of the disease is more common could cause that to change.
In a test conducted last year as part of the licensing for a Chagas' test, 30 donors tested positive from an estimated 150,000 blood samples.
The Community Blood Bank, based in Rancho Mirage, has been testing for Chagas' disease since shortly after the federal Food and Drug Administration licensed a test to detect it in February. The organization serves six hospitals.
Since then, one blood donation made in May has been found conclusively to contain the Chagas' disease parasite, and another made earlier this week has tentatively been found to contain the parasite, spokeswoman Debra Kay Ahlers said Friday. A conclusive test on the second sample likely will not be completed for at least two weeks, she said.
"Our staff is pretty sure that it will come back confirmed," Ahlers said. "It shows that the possibility of contracting Chagas is real."
The largest blood bank in the region, however, has not tested for the disease, and, barring additional information, it does not plan to do so. The Blood Bank of San Bernardino and Riverside Counties, which serves more than five times as many hospitals as the Community Blood Bank does, does not believe the testing is warranted, said Dr. Frederick Axelrod, the blood bank's president and CEO.
The bigger question, Axelrod said, is not whether the disease exists in donated blood but whether it can be passed on in a transfusion.
"The blood-transfusing community believes the risk in the majority of the products is almost zero because of refrigeration and the freezing renders the parasite noninfectious," Axelrod said. "Even though there are donors who are at-risk, it appears the transmission, in terms of patients getting it, is very weak."