ANAHEIM, Calif. -- In the 10 months since the Food and Drug Administration (FDA) licensed the first blood-screening test for Chagas' disease, some 241 blood donations in the United States have tested positive, indicating donor exposure to the parasite known to cause this serious and potentially fatal parasitic infection, according to data released today at the annual meeting of American Association of Blood Banks (AABB). The test is manufactured by Ortho-Clinical Diagnostics, Inc.
Chagas'-positive donations have been reported in 34 states with the highest concentration in
During presentations at the conference today, blood safety experts also said they are investigating new cases of transmissions of Chagas' disease that may have occurred through blood transfusions and via insect bites from bugs known to carry the parasite. Such cases have been extremely rare, or have gone undocumented, in the
"While we have known that Chagas' disease was present in
The American Red Cross was among the first blood collection agencies in the
"Ensuring the safety of the blood supply is a major public health priority, and one that our company is proud to play a role in," said Cliff
In additional developments, public health authorities in
Also called American trypanosomiasis, Chagas' disease is an infection caused by the blood-borne parasite Trypanosoma cruzi, or T.cruzi. The disease is endemic to most countries in Central and South America, as well as Mexico. Transmission occurs through insect bites, blood transfusions, organ transplants and via infected pregnant women to children in utero. Early infection is usually mild and unrecognized, but persists lifelong and may lead to organ damage, particularly of the heart and esophagus, causing an estimated 50,000 deaths annually worldwide. Infection also can be severe in people whose immune systems are suppressed, such as organ transplant recipients. According to the CDC, as many as 8 million to 11 million people in Mexico, Central America and South America have Chagas' disease. (1) Most do not know they are infected. Chagas' disease can be treated successfully if detected soon after the infection occurs, but there is no cure once the disease has entered the chronic stage.
In December 2006, Ortho-Clinical Diagnostics received FDA approval for the ORTHO(R) T.cruzi ELISA Test System. The test detects antibodies to the Trypanosoma cruzi parasite. In clinical trials, the ORTHO(R) T.cruzi ELISA Test System demonstrated 100 percent sensitivity with parasite positive and serological positive populations, and demonstrated an observed specificity of greater than 99.99 percent. When the FDA approved the test, the agency said: "This new test identifies infected donors and therefore can reduce the risk of disease transmission through blood transfusion or organ transplantation."
The company will seek FDA approval to expand use of its test for Chagas' disease in tissue and cell transplants (cadaveric testing) and for general diagnostic purposes.
Reference: (1) Updated CDC estimates as of March 2007. Earlier CDC estimates said the number of people infected with Chagas' disease worldwide ranged from 16 million to 18 million. Experts suggest that the decline may be attributable, at least in part, to effective prevention and intervention programs initiated in central and south America
Source: Ortho-Clinical Diagnostics, Inc.