Public health impacts of donor screening for T. cruzi infection

1. Public health impacts of donor screening for T. cruzi infection Blood Products Advisory Committee April 26, 2007 Susan P. Montgomery, DVM MPH Division of Parasitic Diseases Centers for Disease Control and Prevention Atlanta, GA

2. Chagas disease review • Acute phase lasts ~4 - 8 weeks, often asymptomatic • Chronic phase usually lifelong • Indeterminate stage is asymptomatic • 20 - 40% develop chronic disease after several years to decades • Cardiac • Gastrointestinal • Anti-parasitic treatment is most effective during early infection

3. Screening for T. cruzi infection • Makes the blood supply safer • Donor infections are identified and donors are directed to seek care • Lookback investigations may identify transfusion-transmitted disease

4. Public health impacts of screening: Who is affected • Donors, their families and communities • Healthcare providers • Public health systems

5. Donors as sentinels in the community • Congenital transmission of Chagas disease • Women of childbearing age • Children of positive women • Family members and friends with similar exposure history in endemic countries

6. Chagas disease and Hispanic donors • Donors don’t know they are infected • Blood centers recruiting donors from the Hispanic communities • Most T. cruzi infections acquired in endemic countries of Latin America

7. U.S. foreign born population from Latin America* • 33.5 million people are foreign born • 17.9 million (> 50%) are from Latin America, most from Central America • Most live in West and South states • More likely to be aged 14—64 years • More likely < high school level of education • More likely low income • 28% income less than $20,000/year • 21.6% < poverty level (23.6% Central America) *U.S. Census Bureau, 2003 Current Population Survey

8. Donor perceptions of Chagas disease • Chagas disease well known in rural areas of endemic countries • Stigma attached to infection status • Perception that nothing can be done • Poor availability of drug • Lack of access to appropriate treatment • Emphasis on vector control, not patient treatment

9. Potential barriers to seeking carein the US • Lack of health insurance or under-insured • Language barriers • Immigration status • Employment concerns • Time off from work for medical appointments • Disease limits ability to work

10. US healthcare provider perceptions • Awareness of disease is limited • Training may be minimal and outdated • Domain of tropical disease specialists • Changes in standard of care • Increasing evidence for benefit of treatment during chronic phase • Advances in cardiology mean better supportive treatment options • More aggressive approach to congenital transmission risk control

11. Potential barriers to providing patient care • Insurance coverage may limit the clinical evaluation • No gold standard diagnostic test • Screening assay specificity questions • Limited testing choices to confirm diagnosis • Maintaining longterm followup because of possible disease progression

12. Public health perceptions • Most state and local health departments have little familiarity with Chagas disease and the burden • Chagas disease usually ranks low against competing priorities

13. Barriers to public health response • Lack of resources • State laboratory capabilities limited • Lack of resources to provide care, followup family members and children of infected mothers • Donors may not seek care • Language barriers • Political barriers

14. Public health impacts of screening: Response • Increase awareness/knowledge of Chagas disease, especially the immigrant community • Cross cultural communications • This is a health problem, not a political issue • Inform blood bankers, healthcare providers and public health officials about Chagas disease • Ensure anti-parasitic treatment is available • Establish public health surveillance for Chagas disease in the US

15. Health communication/education • Coordinate with blood collection agencies on donor counseling and referral • CDC Chagas disease web pages updated and translated • Plans to work with Hispanic advocacy groups • Hispanic community knowledge/attitudes/practices (KAP) • Hispanic community healthcare providers KAP

16. Educating healthcare providers • MMWR published February 2007 • Issue clinical case management guidance (expected June 2007) • Present at national medical and public health conferences • Clinical pre-meeting course at ASTMH annual meeting, November 2007

17. CDC clinical support • Increase anti-parasitic drug capacity • Increase supply of nifurtimox • Adding benznidazole • Respond to individual physician and donor inquiries about Chagas disease • Work with local hospitals to establish centers of excellence for Chagas disease

18. Public health and surveillance • Coordinate public health response at federal, state, and local level • Facilitate collaborations between state/local health departments and blood banks • Collect data on identified cases of Chagas disease to define epidemiology • AABB Biovigilance program • Clinical cases

19. For more information on Chagas disease • CDC Chagas disease webpage http://www.cdc.gov/ncidod/dpd/parasites/chagasdisease/default.htm • MMWR on blood screening for Chagas disease http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5607a2.htm • All inquires: CDC Parasitic Diseases Branch Public Inquiries (770) 488-7775