23 research outputs found
Malaria parasite detection increases during pregnancy in wild chimpanzees
Background: The diversity of malaria parasites (Plasmodium sp.) infecting chimpanzees (Pan troglodytes) and their close relatedness with those infecting humans is well documented. However, their biology is still largely unexplored and there is a need for baseline epidemiological data. Here, the effect of pregnancy, a well-known risk factor for malaria in humans, on the susceptibility of female chimpanzees to malaria infection was investigated.
Methods: A series of 384 faecal samples collected during 40 pregnancies and 36 post-pregnancies from three habituated groups of wild chimpanzees in the Tai National Park, Cote d'Ivoire, were tested. Samples were tested for malaria parasites by polymerase chain reaction (PCR) and sequencing. Data were analysed using a generalized linear mixed model.
Results: Probability of malaria parasite detection significantly increased towards the end of pregnancy and decreased with the age of the mother.
Conclusions: This study provides evidence that susceptibility to malaria parasite infection increases during pregnancy, and, as shown before, in younger individuals, which points towards similar dynamics of malaria parasite infection in human and chimpanzee populations and raises questions about the effects of such infections on pregnancy outcome and offspring morbidity/mortality
Ebola virus disease: an orphan zoonosis ?
The gigantic Ebola virus disease
outbreak that recently swept several West African countries has revealed how little we know
about this infectious disease. The question of the animal reservoir of this zoonosis remains
particularly mysterious. Bats seem to be involved in the ecology of the virus but it remains
unclear whether or not they may be at the origin of spill-over events towards humans. Almost
40 years after the discovery of the Ebola virus, this short communication offers a summary
of the progresses made and an outlook on upcoming efforts to solve this outstanding
question.La terrible épidémie de
maladie Ă virus Ebola qui a balayĂ© lâAfrique de lâOuest a mis en Ă©vidence combien nos
connaissances sur cette maladie infectieuse sont limitées. Une question particuliÚrement
mystĂ©rieuse reste celle du rĂ©servoir animal de cette zoonose. Lâimplication des
chauves-souris dans lâĂ©cologie du virus semble probable mais il nâest pas encore Ă©tabli
quâelles jouent un rĂŽle dans sa transmission Ă lâhomme. PrĂšs de 40 ans aprĂšs la dĂ©couverte
du virus, cette communication se propose de faire le point sur les savoirs accumulés et de
dégager des pistes de réflexion utiles
Patterns of foraging activity and fidelity in a Southeast Asian flying fox
Background: Improved understanding of the foraging ecology of bats in the face of ongoing habitat loss and modification worldwide is essential to their conservation and maintaining the substantial ecosystem services they provide. It is also fundamental to assessing potential transmission risks of zoonotic pathogens in human-wildlife interfaces. We evaluated the influence of environmental and behavioral variables on the foraging patterns of Pteropus lylei (a reservoir of Nipah virus) in a heterogeneous landscape in Cambodia. Methods: We employed an approach based on animal-movement modeling, which comprised a path-segmentation method (hidden Markov model) to identify individual foraging-behavior sequences in GPS data generated by eight P. lylei. We characterized foraging localities, foraging activity, and probability of returning to a given foraging locality over consecutive nights. Generalized linear mixed models were also applied to assess the influence of several variables including proxies for energetic costs and quality of foraging areas. Results: Bats performed few foraging bouts (area-restricted searches) during a given night, mainly in residential areas, and the duration of these decreased during the night. The probability of a bat revisiting a given foraging area within 48âh varied according to the duration previously spent there, its distance to the roost site, and the corresponding habitat type. We interpret these fine-scale patterns in relation to global habitat quality (including food-resource quality and predictability), habitat-familiarity and experience of each individual. Conclusions: Our study provides evidence that heterogeneous human-made environments may promote complex patterns of foraging-behavior and short-term re-visitation in fruit bat species that occur in such landscapes. This highlights the need for similarly detailed studies to understand the processes that maintain biodiversity in these environments and assess the potential for pathogen transmission in human-wildlife interfaces
Bacillus cereus Biovar Anthracis Causing Anthrax in Sub-Saharan AfricaâChromosomal Monophyly and Broad Geographic Distribution
Through full genome analyses of four atypical Bacillus cereus isolates, designated B. cereus biovar anthracis, we describe a distinct clade within the B. cereus group that presents with anthrax-like disease, carrying virulence plasmids similar to those of classic Bacillus anthracis. We have isolated members of this clade from different mammals (wild chimpanzees, gorillas, an elephant and goats) in West and Central Africa (CĂŽte dâIvoire, Cameroon, Central African Republic and Democratic Republic of Congo). The isolates shared several phenotypic features of both B. anthracis and B. cereus, but differed amongst each other in motility and their resistance or sensitivity to penicillin. They all possessed the same mutation in the regulator gene plcR, different from the one found in B. anthracis, and in addition, carry genes which enable them to produce a second capsule composed of hyaluronic acid. Our findings show the existence of a discrete clade of the B. cereus group capable of causing anthrax-like disease, found in areas of high biodiversity, which are possibly also the origin of the worldwide distributed B. anthracis. Establishing the impact of these pathogenic bacteria on threatened wildlife species will require systematic investigation. Furthermore, the consumption of wildlife found dead by the local population and presence in a domestic animal reveal potential sources of exposure to humans
Nonhuman primates across sub-Saharan Africa are infected with the yaws bacterium Treponema pallidum subsp. pertenue
Dear Editor, The bacterium Treponema pallidum (TP) causes human syphilis (subsp. pallidum; TPA), bejel (subsp. endemicum; TEN), and yaws (subsp. pertenue; TPE) (1). Although syphilis has reached a worldwide distribution (2), bejel and yaws have remained endemic diseases. Bejel affects individuals in dry areas of Sahelian Africa and Saudi Arabia, whereas yaws affects those living in the humid tropics (1). Yaws is currently reported as endemic in 14 countries, and an additional 84 countries have a known history of yaws but lack recent epidemiological data (3,4). Although this disease was subject to global eradication efforts in the mid-20th century, it later reemerged in West Africa, Southern Asia, and the Pacific region (5). New large-scale treatment options triggered the ongoing second eradication campaign, the goal of which is to eradicate yaws globally by 2020 (5).
References:
(1) Giacani, L. & Lukehart, S.A. The endemic treponematoses. Clin. Microbiol. Rev. 27, 89â115 (2014).
(2) Arora, N. et al. Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster. Nat. Microbiol. 2, 16245 (2016).
(3) Marks, M. Yaws: towards the WHO eradication target. Trans. R Soc. Trop. Med. Hyg. 110, 319â320 (2016).
(4) World Health Organization. Eradication of yaws: procedures for verification and certification of interruption of transmission (World Health Organization, Geneva, 2018).
(5) Asiedu, K., Fitzpatrick, C. & Jannin, J. Eradication of yaws: historical efforts and achieving WHOâs 2020 target. PLoS Negl. Trop. Dis. 8, e3016 (2014)
Persistent anthrax as a major driver of wildlife mortality in a tropical rainforest
Anthrax is a globally important animal disease and zoonosis. Despite this, our current knowledge of anthrax ecology is largely limited to arid ecosystems, where outbreaks are most commonly reported. Here we show that the dynamics of an anthrax-causing agent, Bacillus cereus biovar anthracis, in a tropical rainforest have severe consequences for local wildlife communities. Using data and samples collected over three decades, we show that rainforest anthrax is a persistent and widespread cause of death for a broad range of mammalian hosts. We predict that this pathogen will accelerate the decline and possibly result in the extirpation of local chimpanzee (Pan troglodytes verus) populations. We present the epidemiology of a cryptic pathogen and show that its presence has important implications for conservation
Persistent anthrax as a major driver of wildlife mortality in a tropical rainforest
Anthrax is a globally important animal disease and zoonosis. Despite this, our current knowledge of anthrax ecology is largely limited to arid ecosystems, where outbreaks are most commonly reported. Here we show that the dynamics of an anthrax-causing agent, Bacillus cereus biovar anthracis, in a tropical rainforest have severe consequences for local wildlife communities. Using data and samples collected over three decades, we show that rainforest anthrax is a persistent and widespread cause of death for a broad range of mammalian hosts. We predict that this pathogen will accelerate the decline and possibly result in the extirpation of local chimpanzee (Pan troglodytes verus) populations. We present the epidemiology of a cryptic pathogen and show that its presence has important implications for conservation
Nonhuman primates across sub-Saharan Africa are infected with the yaws bacterium Treponema pallidum subsp. pertenue
The bacterium Treponema pallidum (TP) causes human syphilis (subsp. pallidum; TPA), bejel (subsp. endemicum; TEN), and yaws (subsp. pertenue; TPE)1. Although syphilis has reached a worldwide distribution2, bejel and yaws have remained endemic diseases. Bejel affects individuals in dry areas of Sahelian Africa and Saudi Arabia, whereas yaws affects those living in the humid tropics1. Yaws is currently reported as endemic in 14 countries, and an additional 84 countries have a known history of yaws but lack recent epidemiological data3,4. Although this disease was subject to global eradication efforts in the mid-20th century, it later reemerged in West Africa, Southern Asia, and the Pacific region5. New large-scale treatment options triggered the ongoing second eradication campaign, the goal of which is to eradicate yaws globally by 20205