Immunocompetent infants as a human reservoir for Pneumocystis jirovecii: rapid screening by non-invasive sampling and real-time PCR at the mitochondrial large subunit rRNA gene.

We tested a real-time PCR assay targeting the Pneumocystis jirovecii mitochondrial large subunit rRNA gene on 240 archival nasopharyngeal aspirates from non-immunosuppressed infants. The sensitivity of this assay appeared close to that of a conventional nested-PCR assay targeting the same locus. Because of its one-step procedure, and its sensitivity and rapidity, the real-time PCR assay is particularly suitable for screening individuals parasitized by P. jirovecii within large populations.