# Presentation: 257758

## Public health impacts of donor screening for T. cruzi infection

**Susan P. Montgomery, DVM MPH**
**Division of Parasitic Diseases**
**Centers for Disease Control and Prevention**
**Atlanta, GA**

**Blood Products Advisory Committee**** April 26, 2007**

## 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**

## 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**

## Public health impacts of screening: Who is affected

**Donors, their families and communities**
**Healthcare providers **
**Public health systems**

## 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**

## 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**

## 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**

## 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**

## Potential barriers to seeking carein 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**

## 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**

## 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**

## 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 **

## 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**

## 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**

## 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**

## 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**

## 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**

## 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**

## For more information on Chagas disease

**CDC Chagas disease webpage **_[http://www.cdc.gov/ncidod/dpd/parasites/chagasdisease/default.htm](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](http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5607a2.htm)_
**All inquires: CDC Parasitic Diseases Branch Public Inquiries (770) 488-7775**