New test scans for blood parasite
HEALTH | 'Kissing bug' mainly found in Latin America, but disease has spread through patients' transfusions
October 29, 2007
BY JIM RITTER Health Reporterfirstname.lastname@example.org
Chagas, which is caused by a parasite that bites on the face, will be screened for by blood banks along with better-known ailments like AIDS, syphilis and hepatitis.
The disease, called Chagas, is caused by a parasite transmitted by a bug that bites on the face.
The "kissing bug" is mainly found in rural areas of Latin America. But there are seven known cases in the United States and Canada in which patients have gotten Chagas from blood donors.
Since blood banks began using the test in January, they have found 241 donations contaminated with the Chagas parasite. The chance of getting the disease from such blood is probably less than 10 percent, said American Red Cross scientific officer Susan Stramer.
A Chagas screening test, made by Ortho-Clinical Diagnostics, costs between $5 and $10 per donation.
"The cost is excessively high -- at least twice what we pay for other comparable tests," Stramer said.
Ortho-Clinical senior vice president Steve Dnistrian said the cost is justified by "a lot of investment made in clinical trials and research and development."
As many as 11 million people in Latin America have Chagas. Many don't know it because initial symptoms such as mild fever and fatigue fade away.
But years later, about 30 percent of patients develop serious complications, including enlarged heart, heart failure, cardiac arrest or intestinal complications.
Red Cross screens every donation for Chagas. But LifeSource blood banks, which serve the Chicago area, screen only those donors who say they were born in Mexico, Central America or South America or have lived or traveled in those regions for at least six months.
Abbott Laboratories is developing a competing screening test, and LifeSource soon will begin testing it on every consenting donor.
Stramer said if the Abbott test is approved for general use, the competition might reduce the cost of Chagas screening.