Chagas disease, congenital
2025 Case Definition

Laboratory Criteria

Confirmatory Chagas Disease:**, ***

• Visualization of T. cruzi by microscopy (e.g., wet mount-microscopic examination, thick and thin smears-Giemsa stain) performed on any tissue or body fluid (collected from the fetus or infant within three months of delivery to gestational parent),

OR

• Detection of T. cruzi DNA by molecular testing (e.g., NAAT, metagenomic sequencing) performed on any tissue or body fluid (collected from the fetus or infant within three months of delivery to gestational parent).

Note: The categorical labels used here to stratify laboratory evidence are intended to support the standardization of case classifications for public health surveillance. The categorical labels should not be used to interpret the utility or validity of any laboratory test methodology.

** See Appendix 1 for more information related to signs and syndromes of acute and congenital Chagas disease  .

*** Individuals experiencing reactivation may test positive using molecular testing or microscopic observation. These individuals can be counted as a chronic case pending positive serology that meets the chronic case definition. In the context of transplant recipients, case classification should be informed by whether the positive result may reflect an acute, donor-derived infection or chronic infection in a case experiencing reactivation.

Confirmed

A fetus (≥20 weeks or ≥350g) or an infant who meets congenital Chagas disease confirmatory laboratory evidence in the absence of other known routes of transmission.**

** See Appendix 1 for more information related to signs and syndromes of acute and congenital Chagas disease  .

• Chagas disease | 2025 Case Definition