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Cryptic diversity in hymenolepidid tapeworms infecting humans
Agathe Nkouawa1, Voitto Haukisalmi2, Tiaoying Li3
1Department of Parasitology, Asahikawa Medical University, Asahikawa, Japan.
Parasitology International
|November 6, 2015
Summary
A new tapeworm species, distinct from common human parasites Hymenolepis diminuta and Hymenolepis nana, was found in a Chinese woman. This discovery expands the known range of tapeworm species causing human hymenolepiasis.
Area of Science:
- Parasitology
- Molecular Phylogenetics
- Medical Entomology
Background:
- Human hymenolepiasis is typically caused by Hymenolepis diminuta and Hymenolepis nana.
- Epidemiological surveys are crucial for identifying novel parasitic infections in human populations.
Observation:
- An adult hymenolepidid tapeworm was isolated from a 52-year-old Tibetan woman in Sichuan, China.
- Morphological identification of proglottids was not possible due to their condition.
Findings:
- Phylogenetic analysis of nuclear 28S ribosomal DNA and mitochondrial cytochrome c oxidase subunit 1 revealed the human isolate is genetically distinct from H. diminuta and H. nana.
- The study suggests the human tapeworm isolate is a sister species to Hymenolepis hibernia, previously identified in Eurasian Apodemus mice.
Implications:
- The findings indicate that hymenolepidid tapeworms causing human infections are more diverse than previously recognized.
- This expands the known spectrum of tapeworm parasites capable of infecting humans, necessitating updated diagnostic and epidemiological considerations.
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