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Table 1.  

Birth country Trypanosoma cruzi infection prevalence, % Estimated no. infected adults by age group
All ages 18–34 35–49 ≥50
Argentina 3.64 14,463 600 2,592 11,271
Belize 0.33 344 15 53 276
Bolivia 18.3 27,335 1,650 5,262 20,423
Brazil 0.61 3,865 379 1,049 2,437
Chile 0.70 1,560 69 226 1,265
Colombia 0.51 7,840 398 1,260 6,182
Costa Rica 0.17 289 18 55 216
Ecuador 1.38 11,200 719 2,316 8,165
El Salvador 1.90 41,788 3,287 11,260 27,241
Guatemala 1.13 14,143 1,846 4,109 8,188
Guyana, French Guiana, Suriname 0.84 5,171 183 746 4,242
Honduras 0.65 5,208 671 1,606 2,931
Mexico 0.73 141,554 10,730 36,413 94,411
Nicaragua 0.52 2,773 131 528 2,114
Panama 0.52 1,810 64 233 1,513
Paraguay 2.13 679 75 134 470
Peru 0.44 4,125 192 728 3,205
Uruguay 0.24 234 11 39 184
Venezuela 0.71 3,330 315 842 2,173
All Latin America countries 1.64 287,711 21,353 69,451 196,907

Table 1. Estimates of the number of Latin America–born adults with Chagas disease in the United States

Table 2.  

Age, y No. infected No. (%) with Chagas cardiomyopathy
18–34 21,353 854 (4)
35–49 69,451 6,945 (10)
≥50 196,907 49,227(25)
All ages 287,711 57,027 (19.8)

Table 2. Estimated Latin America–born persons with Chagas cardiomyopathy in the United States

Table 3.  

Maternal age, y No. women infected Live births/1,000 women* No. births to infected women No. infected infants/y
Lower limit, 1% Upper limit, 5%
18–19 683 64.3 44 0 2
20–24 2,134 114.4 244 2 12
25–29 3,051 136.4 416 4 21
30–34 3,933 117.6 463 5 23
35–39 11,553 66.6 770 8 38
40–44 11,573 17.7 205 2 10
45–49 10,356 1.2 13 0 1
All ages 43,283   2,154 22 108

Table 3. Estimated annual births to Trypanosoma cruzi–infected women and congenital infections, United States

*Age-specific birth rates for all Hispanic women in 2017 multiplied by 1.22 to correct for higher birth rates among foreign-born Hispanic women (see Methods).

Table 4.  

Location Trypanosoma cruzi –infected adults Prevalence in total adult population, % Prevalence in Latin America–born adult population, %
Top 10 in total number of T. cruzi– infected adults

Los Angeles-Long Beach-Anaheim, CA

44,768 0.43 1.97

New York-Newark-Jersey City, NY-NJ-PA

28,304 0.18 1.89

Washington-Arlington-Alexandria, DC-VA-MD-WV

17,745 0.38 3.85

Miami-Fort Lauderdale-West Palm Beach, FL

15,586 0.32 1.93

Houston-The Woodlands-Sugar Land, TX

14,175 0.29 1.60

Riverside-San Bernardino-Ontario, CA

11,070 0.33 1.71

Chicago-Naperville-Elgin, IL-IN-WI

10,931 0.15 1.51

Dallas-Fort Worth-Arlington, TX

9,887 0.19 1.37

San Francisco-Oakland-Hayward, CA

6,898 0.18 1.76

San Diego-Carlsbad, CA

5,730 0.22 1.54
Top 10 in overall T. cruzi prevalence

El Centro, CA

956 0.74 1.76

Laredo, TX

1,025 0.57 1.49

McAllen-Edinburg-Mission, TX

3,193 0.56 1.49

El Paso, TX

3,387 0.56 1.77

Brownsville-Harlingen, TX

1,564 0.54 1.66

Yuma, AZ

738 0.48 1.56

Los Angeles-Long Beach-Anaheim, CA

44,768 0.43 1.97

Salinas, CA

1,503 0.41 1.35

Merced, CA

756 0.40 1.46

Washington-Arlington-Alexandria, DC-VA-MD-WV

17,745 0.38 3.85

Table 4. US metropolitan areas with the highest estimated prevalence of Chagas disease


Updated Estimates and Mapping for Prevalence of Chagas Disease Among Adults, United States

  • Authors: Amanda Irish, DVM; Jeffrey D. Whitman, MD; Eva H. Clark, MD; Rachel Marcus, MD; Caryn Bern, MD
  • CME / ABIM MOC Released: 6/17/2022
  • Valid for credit through: 6/17/2023
Start Activity

  • Credits Available

    Physicians - maximum of 1.00 AMA PRA Category 1 Credit(s)™

    ABIM Diplomates - maximum of 1.00 ABIM MOC points

    You Are Eligible For

    • Letter of Completion
    • ABIM MOC points

Target Audience and Goal Statement

This activity is intended for primary care physicians, infectious disease specialists, and other physicians who care for patients at risk for Chagas disease.

The goal of this activity is to better be able to evaluate the epidemiology of Chagas disease in the United States.

Upon completion of this activity, participants will:

  • Evaluate the prognosis of Chagas disease
  • Analyze the epidemiology of Chagas disease in the United States
  • Distinguish US metropolitan areas with the highest rates of Chagas disease
  • Analyze the prevalence of Chagas disease based on country of origin in Latin America


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  • Amanda Irish, DVM

    University of California, San Francisco

  • Jeffrey D. Whitman, MD

    University of California, San Francisco

  • Eva H. Clark, MD

    Baylor College of Medicine
    Houston, Texas

  • Rachel Marcus, MD

    Medstar Union Memorial Hospital and LASOCHA
    Washington, DC

  • Caryn Bern, MD

    University of California, San Francisco

CME Author

  • Charles P. Vega, MD

    Health Sciences Clinical Professor of Family Medicine
    University of California, Irvine School of Medicine
    Irvine, California


    Charles P. Vega, MD, has the following relevant financial relationships:
    Advisor or consultant for: GlaxoSmithKline; Johnson & Johnson Pharmaceutical Research & Development, L.L.C.


  • Dana C. Dolan, BS

    Emerging Infectious Diseases

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    Associate Director, Accreditation and Compliance
    Medscape, LLC


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Updated Estimates and Mapping for Prevalence of Chagas Disease Among Adults, United States

Authors: Amanda Irish, DVM; Jeffrey D. Whitman, MD; Eva H. Clark, MD; Rachel Marcus, MD; Caryn Bern, MDFaculty and Disclosures

CME / ABIM MOC Released: 6/17/2022

Valid for credit through: 6/17/2023


Abstract and Introduction


We combined American Community Survey data with age-specific Trypanosoma cruzi prevalence derived from US surveys and World Health Organization reports to yield estimates of Chagas disease in the United States, which we mapped at the local level. In addition, we used blood donor data to estimate the relative prevalence of autochthonous T. cruzi infection. Our estimates indicate that 288,000 infected persons, including 57,000 Chagas cardiomyopathy patients and 43,000 infected reproductive-age women, currently live in the United States; 22–108 congenital infections occur annually. We estimated ≈10,000 prevalent cases of locally acquired T. cruzi infection. Mapping shows marked geographic heterogeneity of T. cruzi prevalence and illness. Reliable demographic and geographic data are key to guiding prevention and management of Chagas disease. Population-based surveys in high prevalence areas could improve the evidence base for future estimates. Knowledge of the demographics and geographic distribution of affected persons may aid practitioners in recognizing Chagas disease.


Six million persons are estimated to have Chagas disease in the Americas; 20%–30% of those cases will progress to cardiac or gastrointestinal disease[1]. Early treatment of infection with the causative parasite, Trypanosoma cruzi, provides the best chance to decrease progression risk; cure rates are ≥60% in those treated as children[2,3]. Cure rates among adults are unclear; the accepted test of cure is reversion to negative serologic test results, which requires years to decades, and the time to negative serologic results is inversely proportional to the duration of infection[4]. Because the date of T. cruzi infection is nearly always unknown, age is commonly used as a proxy for duration. Infected persons are typically asymptomatic for decades. In those with established Chagas cardiomyopathy, antiparasitic treatment is unlikely to alter heart disease progression[5]. Thus, early, active screening during the asymptomatic period is essential to achieve timely diagnosis and effective treatment. Since the establishment of regional control programs in the 1990s, many Latin America countries have mounted community- and facility-based programs, most commonly focused on screening of children and pregnant women[6,7]. No such large-scale programs exist in the United States.

Enzootic transmission by local triatomine species occurs across the southern United States from coast to coast; Lynn et al. summarized 76 suspected or confirmed autochthonous human T. cruzi infections[8]. However, locally acquired infections are vastly outnumbered by those acquired by immigrants from Latin America in their countries of origin before arrival in the United States. No nationally representative T. cruzi prevalence data exist for the United States; disease burden estimates have been based on reported national prevalence figures from Latin America countries. These estimates suggest that 240,000–350,000 US residents of Latin America origin may have T. cruzi infection[9]. However, infection rates are heterogeneous within countries, so national-level prevalence estimates may not reflect prevalence among US immigrants.

Calls for more widespread screening and diagnostic testing for Chagas disease in the United States are growing[10–12]. Finer-scale geographic data would be of great help in the targeting of such efforts. Local screening of at-risk populations in Los Angeles, California; the District of Columbia; and the Boston, Massachusetts, metropolitan areas provide a more accurate reflection of prevalence in some US populations[13–15]. Using data from the American Community Survey (ACS)[16], we developed new age-structured estimates and interactive maps of Chagas disease prevalence at the local level. We present these data to support geographic targeting of screening efforts and setting priorities for healthcare providers and public health outreach to address Chagas disease in the United States.