Geographic variation in the sensitivity of recombinant antigen-based rapid tests for chronic Trypanosoma cruzi infection.
Chagas disease affects 8-11 million people throughout the Americas. Early detection is crucial for timely treatment and to prevent non-vectorial transmission. Recombinant antigen-based rapid tests had high sensitivity and specificity in laboratory evaluations, but no Peruvian specimens were included in previous studies. We evaluated Stat-Pak and Trypanosoma Detect rapid tests in specimens from Bolivia and Peru. Specimens positive by three conventional assays were confirmed positives; specimens negative by two or more assays were confirmed negatives. In Bolivian specimens, Stat-Pak and Trypanosoma Detect tests were 87.5% and 90.7% sensitive, respectively; both showed 100% specificity. Sensitivity in Peruvian specimens was much lower: 26.6-33.0% (Stat-Pak) and 54.3-55.2% (Trypanosoma Detect); both had specificities > 98%. Even in Bolivian specimens, these sensitivities are inadequate for stand-alone screening. The low sensitivity in Peru may be related to parasite strain differences. Chagas disease rapid tests should be field tested in each geographic site before widespread implementation for screening.
Verani
Jennifer R
JR
Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. jverani@cdc.gov
Seitz
Amy
A
Gilman
Robert H
RH
LaFuente
Carlos
C
Galdos-Cardenas
Gerson
G
Kawai
Vivian
V
de LaFuente
Elizabeth
E
Ferrufino
Lisbeth
L
Bowman
Natalie M
NM
Pinedo-Cancino
Viviana
V
Levy
Michael Z
MZ
Steurer
Francis
F
Todd
Charles W
CW
Kirchhoff
Louis V
LV
Cabrera
Lilia
L
Verastegui
Manuela
M
Bern
Caryn
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology*; D001838:Bolivia / Q000453:epidemiology; D014355:Chagas Disease / Q000175:diagnosis* / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008875:Middle Aged; D010568:Peru / Q000453:epidemiology; D011247:Pregnancy; D015531:Radioimmunoprecipitation Assay; D012680:Sensitivity and Specificity; D013997:Time Factors; D014349:Trypanosoma cruzi / Q000276:immunology*; D055815:Young Adult
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan