Scientific Reports (May 2021)

Heterogeneity in patterns of helminth infections across populations of mountain gorillas (Gorilla beringei beringei)

  • Klara J. Petrželková,
  • Carine Uwamahoro,
  • Barbora Pafčo,
  • Barbora Červená,
  • Peter Samaš,
  • Antoine Mudakikwa,
  • Richard Muvunyi,
  • Prosper Uwingeli,
  • Kirsten Gilardi,
  • Julius Nziza,
  • Jean Bosco Noheri,
  • Winnie Eckardt,
  • Felix Ndagijimana,
  • Benard Ssebide,
  • Ricky Okwirokello,
  • Fred Nizeyimana,
  • Eddy Kambale Syaluha,
  • Gaspard Nzayisenga,
  • Luis Flores Girón,
  • Méthode Bahizi,
  • Adrien Emile Ntwari,
  • Jean-Paul Lukusa,
  • Jean Claude Tumushime,
  • Damien Mangura,
  • Jeff Mapilanga,
  • Arthur Kalonji,
  • Robert Aruho,
  • Anna Stryková,
  • Zuzana Tehlarová,
  • Rita Cameira,
  • Linda Lowenstine,
  • Jan Šlapeta,
  • Dušan Romportl,
  • Nicola Ferrari,
  • Michael Cranfield,
  • David Modrý

DOI
https://doi.org/10.1038/s41598-021-89283-4
Journal volume & issue
Vol. 11, no. 1
pp. 1 – 14

Abstract

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Abstract Conservation efforts have led to the recovery of the endangered mountain gorilla populations. Due to their limited potential for spatial expansion, population densities increased, which may alter the epidemiology of infectious diseases. Recently, clinical gastrointestinal illnesses linked to helminth infections have been recorded in both gorilla populations. To understand drivers and patterns of helminth infections we quantified strongylid and tapeworm infections across both Virunga Massif and Bwindi populations using fecal egg counts. We assessed the impact of age, sex, group size, season and spatial differences used as a proxy, which reflects observed variation in the occurrence of gastrointestinal problems, vegetation types, gorilla subpopulation growth and associated social structure on helminth infections. We revealed striking geographic differences in strongylid infections with higher egg counts mostly in areas with high occurrences of gastrointestinal disease. Increased helminth egg counts were also associated with decreasing group size in some areas. Observed spatial differences may reflect mutual effects of variations in subpopulation growth rates, gorilla social structure, and vegetation associated with altitude across mountain gorilla habitat. Helminth infection intensities in Virunga gorillas were lowest in the youngest and the oldest animals. Elucidating parasite infection patterns of endangered species with low genetic diversity is crucial for their conservation management.