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Transboundary and emerging diseases2021; 69(3); 1617-1624; doi: 10.1111/tbed.14135

Outbreak of equine pythiosis in a southeastern region of Brazil: Environmental isolation and phylogeny.

Abstract: Pythiosis is a disease caused by the oomycete Pythium insidiosum, mainly reported in equines, dogs and humans and directly transmitted through contaminant zoospores in aquatic environments. We report the first outbreak of equine pythiosis in five equines. Wound samples were submitted for diagnostic testing including mycological culture and nested PCR. Treatment approaches consisted of conventional and alternative therapies. Microbiological analyses were performed using water samples from the riverbanks close to where the animals had grazed. All animals were positive for P. insidiosum cultures, and two animals responded successfully to alternative therapy (ozone therapy). After culture and molecular analysis of environmental samples, the presence of P. insidiosum in one section of the Tietê River was confirmed through a 99% sequence identity. Phylogenetic analyses using the cytochrome oxidase II gene showed that the animal isolates clustered in clade I and the environmental isolates clustered in clade III. Although the environmental and wound isolates belonged to different genetic clades, we concluded that the Tietê River is an important source of infection by P. insidiosum and that research concerning environmental isolation of P. insidiosum from rivers and lakes should be strongly facilitated in Brazil.
© 2021 Wiley-VCH GmbH.
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Publication Date: 2021-06-10 PubMed ID: 33991402DOI: 10.1111/tbed.14135Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research focuses on an outbreak of equine pythiosis in a southeastern region of Brazil, tracing its source back to the aquatic environment of the Tiete River, and identifies different genetic clades in animal and environmental samples.

Research Objectives

  • The researchers aimed to investigate the first recorded outbreak of equine pythiosis, a disease mostly found in horses, dogs, and humans, caused by an oomycete called Pythium insidiosum.
  • They sought to determine the cause of the outbreak, as well as evaluate the efficiency of different treatment options.
  • The study also intended to trace the source of the disease, assessing the possible role of the Tiete River where the affected animals had been grazing.

Methodology

  • Wound samples from affected animals were tested through mycological culture and nested PCR to confirm presence of pythiosis.
  • Different treatment approaches, including conventional and alternative (ozone therapy), were administered to the affected animals.
  • Water samples from the Tiete riverbanks were examined to determine if they contained Pythium insidiosum.

Key Findings

  • All the tested animals were confirmed to be suffering from pythiosis based on the presence of P. insidiosum in their wound cultures.
  • Two of the animals responded positively to ozone therapy.
  • The Tiete River was confirmed as a source of P. insidiosum, underpinning the outbreak, as one of its sections exhibited a 99% sequence identity of the oomycete.
  • Phylogenetic analysis revealed that the organisms isolated from the animals and the river belonged to different genetic clades – clade I for animal isolates and clade III for environmental isolates. This implies that the same species interact differently within various ecosystems.

Conclusion

  • The study concluded that the Tiete River was a significant source of the infection. It raises concerns about the need for greater research focusing on the environmental isolation of P. insidiosum, especially in Brazil’s rivers and lakes where the disease’s presence is inferred.

Cite This Article

APA
Paz GSD, Camargo GG, Cury JE, Apolonio EVP, Garces HG, Prado ACD, Chechi JL, Oliveira AL, Watanabe MJ, Bagagli E, Bosco SMG. (2021). Outbreak of equine pythiosis in a southeastern region of Brazil: Environmental isolation and phylogeny. Transbound Emerg Dis, 69(3), 1617-1624. https://doi.org/10.1111/tbed.14135

Publication

Transboundary and emerging diseases
ISSN: 1865-1682
NlmUniqueID: 101319538
Country: Germany
Language: English
Volume: 69
Issue: 3
Pages: 1617-1624

Researcher Affiliations

Paz, Giselle Souza da
  • School of Veterinary Medicine and Animal Science, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Camargo, Gabriel Gasparini
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Cury, José Eduardo
  • Autonomous Veterinarian, Botucatu, Brazil.
Apolonio, Emanuel Vitor Pereira
  • School of Veterinary Medicine and Animal Science, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Garces, Hans Garcia
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Prado, Ana Carolina do
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Chechi, Jessica Luana
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Oliveira, Alana Lucena
  • School of Veterinary Medicine and Animal Science, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Watanabe, Marcos Jun
  • School of Veterinary Medicine and Animal Science, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Bagagli, Eduardo
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.
Bosco, Sandra de Moraes Gimenes
  • School of Veterinary Medicine and Animal Science, UNESP Univ Estadual Paulista, Botucatu, Brazil.
  • Institute of Biosciences of Botucatu, UNESP Univ Estadual Paulista, Botucatu, Brazil.

MeSH Terms

  • Animals
  • Brazil / epidemiology
  • Disease Outbreaks / veterinary
  • Dogs
  • Horse Diseases / epidemiology
  • Horse Diseases / microbiology
  • Horses
  • Phylogeny
  • Pythiosis / epidemiology
  • Pythium / classification

Grant Funding

  • 2018/08009-0 / São Paulo State Research Foundation-FAPESP
  • 2018/17596-7 / São Paulo State Research Foundation-FAPESP
  • Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Citations

This article has been cited 8 times.
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