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. 2011 Aug;85(2):238-42.
doi: 10.4269/ajtmh.2011.10-0664.

Cryptosporidium meleagridis: infectivity in healthy adult volunteers

Cynthia L Chappell  1 , Pablo C Okhuysen, Rebecca C Langer-Curry, Donna E Akiyoshi, Giovanni Widmer, Saul Tzipori
Affiliations

Cryptosporidium meleagridis: infectivity in healthy adult volunteers

Cynthia L Chappell et al. Am J Trop Med Hyg. 2011 Aug.

Abstract

Most Cryptosporidium infections in humans are caused by C. parvum or C. hominis. However, genotyping techniques have identified infections caused by unusual Cryptosporidium species. Cryptosporidium meleagridis has been identified in ≤ 1% of persons with diarrhea, although prevalence is higher in developing nations. We examined the infectivity of C. meleagridis in healthy adults. Five volunteers were challenged with 10(5) C. meleagridis oocysts and monitored six weeks for fecal oocysts and clinical manifestations. Four volunteers had diarrhea; three had detectable fecal oocysts; and one infected volunteer remained asymptomatic. Fecal DNA from two volunteers was amplified by using a polymerase chain reaction specific for the Cryptosporidium small subunit ribosomal RNA gene. Nucleotide sequence of these amplicons was diagnostic for C. meleagridis. All infections were self-limited; oocysts were cleared within ≤ 12 days of challenge. These studies establish that healthy adults can be infected and become ill from ingestion of C. meleagridis oocysts.

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Figures

Figure 1.
Figure 1.
Oocyst shedding (open bars) and diarrhea (shaded bars) in adult volunteers challenged with Cryptosporidium meleagridis oocysts.
See this image and copyright information in PMC

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