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Title: Metagenomic analysis of human-biting cat fleas in urban northeastern United States of America reveals an emerging zoonotic pathogen

An infestation of cat fleas in a research center led to the detection of two genotypes ofCtenocephalides felisbiting humans in New Jersey, USA. The rarer flea genotype had an 83% incidence ofRickettsia asembonensis, a recently described bacterium closely related toR. felis,a known human pathogen. A metagenomics analysis developed in under a week recovered the entireR. asembonensisgenome at high coverage and matched it to identical or almost identical (> 99% similarity) strains reported worldwide. Our study exposes the potential of cat fleas as vectors of human pathogens in crowded northeastern U.S, cities and suburbs where free-ranging cats are abundant. Furthermore, it demonstrates the power of metagenomics to glean large amounts of comparative data regarding both emerging vectors and their pathogens.

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Nature Publishing Group
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Journal Name:
Scientific Reports
Medium: X
Sponsoring Org:
National Science Foundation
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