High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.

Toxoplasma gondii is a zoonotic parasite that can cause severe morbidity and mortality in warm-blooded animals, including marine mammals such as sea otters. Free-ranging cats can shed environmentally resistant T. gondii oocysts in their feces, which are transported through rain-driven runoff from la...

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Main Authors: Sophie Zhu, Lauren Camp, Anika Patel, Elizabeth VanWormer, Karen Shapiro
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2023-12-01
Series:PLoS Neglected Tropical Diseases
Online Access:https://doi.org/10.1371/journal.pntd.0011829
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author Sophie Zhu
Lauren Camp
Anika Patel
Elizabeth VanWormer
Karen Shapiro
author_facet Sophie Zhu
Lauren Camp
Anika Patel
Elizabeth VanWormer
Karen Shapiro
author_sort Sophie Zhu
collection DOAJ
description Toxoplasma gondii is a zoonotic parasite that can cause severe morbidity and mortality in warm-blooded animals, including marine mammals such as sea otters. Free-ranging cats can shed environmentally resistant T. gondii oocysts in their feces, which are transported through rain-driven runoff from land to sea. Despite their large population sizes and ability to contribute to environmental oocyst contamination, there are limited studies on T. gondii oocyst shedding by free-ranging cats. We aimed to determine the frequency and genotypes of T. gondii oocysts shed by free-ranging domestic cats in central coastal California and evaluate whether genotypes present in feces are similar to those identified in sea otters that died from fatal toxoplasmosis. We utilized a longitudinal field study of four free-ranging cat colonies to assess oocyst shedding prevalence using microscopy and molecular testing with polymerase chain reaction (PCR). T. gondii DNA was confirmed with primers targeting the ITS1 locus and positive samples were genotyped at the B1 locus. While oocysts were not visualized using microscopy (0/404), we detected T. gondii DNA in 25.9% (94/362) of fecal samples. We genotyped 27 samples at the B1 locus and characterized 13 of these samples at one to three additional loci using multi locus sequence typing (MLST). Parasite DNA detection was significantly higher during the wet season (16.3%, 59/362) compared to the dry season (9.7%; 35/362), suggesting seasonal variation in T. gondii DNA presence in feces. High diversity of T. gondii strains was characterized at the B1 locus, including non-archetypal strains previously associated with sea otter mortalities. Free-ranging cats may thus play an important role in the transmission of virulent T. gondii genotypes that cause morbidity and mortality in marine wildlife. Management of free-ranging cat colonies could reduce environmental contamination with oocysts and subsequent T. gondii infection in endangered marine mammals and people.
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spelling doaj.art-17f9da43217f471db9703472a9d5df882024-01-04T05:32:33ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27271935-27352023-12-011712e001182910.1371/journal.pntd.0011829High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.Sophie ZhuLauren CampAnika PatelElizabeth VanWormerKaren ShapiroToxoplasma gondii is a zoonotic parasite that can cause severe morbidity and mortality in warm-blooded animals, including marine mammals such as sea otters. Free-ranging cats can shed environmentally resistant T. gondii oocysts in their feces, which are transported through rain-driven runoff from land to sea. Despite their large population sizes and ability to contribute to environmental oocyst contamination, there are limited studies on T. gondii oocyst shedding by free-ranging cats. We aimed to determine the frequency and genotypes of T. gondii oocysts shed by free-ranging domestic cats in central coastal California and evaluate whether genotypes present in feces are similar to those identified in sea otters that died from fatal toxoplasmosis. We utilized a longitudinal field study of four free-ranging cat colonies to assess oocyst shedding prevalence using microscopy and molecular testing with polymerase chain reaction (PCR). T. gondii DNA was confirmed with primers targeting the ITS1 locus and positive samples were genotyped at the B1 locus. While oocysts were not visualized using microscopy (0/404), we detected T. gondii DNA in 25.9% (94/362) of fecal samples. We genotyped 27 samples at the B1 locus and characterized 13 of these samples at one to three additional loci using multi locus sequence typing (MLST). Parasite DNA detection was significantly higher during the wet season (16.3%, 59/362) compared to the dry season (9.7%; 35/362), suggesting seasonal variation in T. gondii DNA presence in feces. High diversity of T. gondii strains was characterized at the B1 locus, including non-archetypal strains previously associated with sea otter mortalities. Free-ranging cats may thus play an important role in the transmission of virulent T. gondii genotypes that cause morbidity and mortality in marine wildlife. Management of free-ranging cat colonies could reduce environmental contamination with oocysts and subsequent T. gondii infection in endangered marine mammals and people.https://doi.org/10.1371/journal.pntd.0011829
spellingShingle Sophie Zhu
Lauren Camp
Anika Patel
Elizabeth VanWormer
Karen Shapiro
High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
PLoS Neglected Tropical Diseases
title High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
title_full High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
title_fullStr High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
title_full_unstemmed High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
title_short High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California.
title_sort high prevalence and diversity of toxoplasma gondii dna in feral cat feces from coastal california
url https://doi.org/10.1371/journal.pntd.0011829
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