title: Congenital Trypanosoma cruzi transmission in Santa Cruz, Bolivia.
abstract: BACKGROUND
  We conducted a study of congenital Trypanosoma cruzi infection in Santa Cruz, Bolivia. Our objective was to apply new tools to identify weak points in current screening algorithms, and find ways to improve them.
  
  
  METHODS
  Women presenting for delivery were screened by rapid and conventional serological tests. For infants of infected mothers, blood specimens obtained on days 0, 7, 21, 30, 90, 180, and 270 were concentrated and examined microscopically; serological tests were performed for the day 90, 180, and 270 specimens. Maternal and infant specimens, including umbilical tissue, were tested by polymerase chain reaction (PCR) targeting the kinetoplast minicircle and by quantitative PCR.
  
  
  RESULTS
  Of 530 women, 154 (29%) were seropositive. Ten infants had congenital T. cruzi infection. Only 4 infants had positive results of microscopy evaluation in the first month, and none had positive cord blood microscopy results. PCR results were positive for 6 (67%) of 9 cord blood and 7 (87.5%) of 8 umbilical tissue specimens. PCR-positive women were more likely to transmit T. cruzi than were seropositive women with negative PCR results (P < .05). Parasite loads determined by quantitative PCR were higher for mothers of infected infants than for seropositive mothers of uninfected infants P < .01). Despite intensive efforts, only 58% of at-risk infants had a month 9 specimen collected.
  
  
  CONCLUSIONS
  On the basis of the low sensitivity of microscopy in cord blood and high rate of loss to follow-up, we estimate that current screening programs miss one-half of all infected infants. Molecular techniques may improve early detection.
authors.affiliation: Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Caryn
authors.initials: C
authors.lastname: Bern
authors.forename: Manuela
authors.initials: M
authors.lastname: Verastegui
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.forename: Carlos
authors.initials: C
authors.lastname: Lafuente
authors.forename: Gerson
authors.initials: G
authors.lastname: Galdos-Cardenas
authors.forename: Maritza
authors.initials: M
authors.lastname: Calderon
authors.forename: Juan
authors.initials: J
authors.lastname: Pacori
authors.forename: Maria
authors.initials: M
authors.lastname: Del Carmen Abastoflor
authors.forename: Hugo
authors.initials: H
authors.lastname: Aparicio
authors.forename: Mark F
authors.initials: MF
authors.lastname: Brady
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Ferrufino
authors.forename: Noelia
authors.initials: N
authors.lastname: Angulo
authors.forename: Sarah
authors.initials: S
authors.lastname: Marcus
authors.forename: Charles
authors.initials: C
authors.lastname: Sterling
authors.forename: James H
authors.initials: JH
authors.lastname: Maguire
mesh_terms: D000818:Animals; D001838:Bolivia; D014355:Chagas Disease / Q000097:blood / Q000175:diagnosis* / Q000469:parasitology / Q000635:transmission*; D016054:DNA, Protozoan / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D014349:Trypanosoma cruzi / Q000235:genetics / Q000502:physiology*
chemical_list: D016054:DNA, Protozoan