Epidemiological study of zoonoses derived from humans in captive chimpanzees

Identification of potentially zoonotic parasites in captive orangutans and semi-captive mandrills: Phylogeny and morphological comparison

Cysts and trophozoites of vestibuliferid ciliates and larvae of Strongyloides were found in fecal samples from captive orangutans Pongo pygmaeus and P. abelii from Czech and Slovak zoological gardens. As comparative material, ciliates from semi-captive mandrills Mandrillus sphinx from Gabon were included in the study. Phylogenetic analysis of the detected vestibuliferid ciliates using ITS1-5.8s-rRNA-ITS2 and partial 18S ribosomal deoxyribonucleic acid (rDNA) revealed that the ciliates from orangutans are conspecific with Balantioides coli lineage A, while the ciliates from mandrills clustered with Buxtonella-like ciliates from other primates. Morphological examination of the cysts and trophozoites using light microscopy did not reveal differences robust enough to identify the genera of the ciliates. Phylogenetic analysis of detected L1 larvae of Strongyloides using partial cox1 revealed Strongyloides stercoralis clustering within the cox1 lineage A infecting dogs, humans, and other primates. The sequences of 18S rDNA support these results. As both B. coli and S. stercoralis are zoonotic parasites and the conditions in captive and semi-captive settings may facilitate transmission to humans, prophylactic measures should reflect the findings.

Giardia duodenalis in a clinically healthy population of captive zoo chimpanzees: Rapid antigen testing, diagnostic real-time PCR and faecal microbiota profiling

Giardia duodenalis is one of the most common intestinal parasites of humans, with a worldwide distribution. Giardia duodenalis has been reported in both wild and captive populations of non-human primates, namely chimpanzees. In this study we investigated an entire troop of clinically healthy chimpanzees (n = 21) for the presence of G. duodenalis and its association with faecal microbiota profile. Faecal samples (n = 26) were collected from the chimpanzee exhibit from a zoo in Sydney, Australia. Diagnosis of G. duodenalis was made using a Rapid Antigen Test (RAT) as a point-of-care-test and compared to a reference standard real-time PCR test. Approximately half of the chimpanzee faecal samples tested positive for G. duodenalis by both RAT (13/26, 50%) and real-time PCR (14/26, 53.85%). The RAT sensitivity was 85.7% (95% CI: 63.8%–96%) and specificity was 91.7% (95% CI: 68.3%–99%) when compared to the in-house real-time PCR. Genotyping of the samples revealed the presence of zoonotic assemblage B. Microscopic analysis revealed the presence of Troglodytella spp. (14/26), Balantioides sp. (syn. Balantidium sp.) (8/26) as well as Entamoeba spp. (3/26). Microbiota profile based on 16S rRNA gene sequencing revealed that the community was significantly different between G. duodenalis positive and negative samples if RAT results were taken into an account, but not real-time PCR diagnostics results. Proteobacteria and Chloroflexi were the significant features in the dataset that separated G. duodenalis positive and negative samples using LEfSe analysis. Being able to rapidly test for G. duodenalis in captive populations of primates assists in point-of-care diagnostics and may better identify animals with subclinical disease. Under the investigated conditions of the zoo setting, however, presence of G. duodenalis either detected by RAT or real-time PCR was not associated with clinically apparent disease in captive chimpanzees.

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Whole troop investigation of healthy captive chimpanzees for Giardia duodenalis.

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Whole chimpanzee troop faecal microbiota profiled.

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Diagnosing G. duodenalis with Rapid Antigen Test (RAT) as a point-of-care-test.

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Comparison of RAT and reference real-time PCR test.

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Presence of G. duodenalis assemblage B.

Comparative survival analyses among captive chimpanzees (Pan troglodytes) in America and Japan

Detailed, long-term datasets on the life histories of long-lived species such as great apes are necessary to understand their survival patterns but are relatively rare. Such information requires prolonged and consistent record-keeping over many generations, so for chimpanzees (Pan troglodytes), this equates to many decades of input. As life history variables can be altered by differences in environmental influences (whether natural or artificial), there is substantial value to being able to compare across populations. Here, we present the first comparative analysis of life history data for two ex situ chimpanzee populations residing in North America (1975–2020; n = 730) and Japan (1980–2020; n = 660). Overall, survival patterns were similar between regions, and the median life expectancy from birth is estimated at 35.7 (95% CI = [32.4–40.0]) years for females and 30.1 (27.3–34.3) years for males across both populations. Females who survive to their first birthday are estimated to survive 42.4 (40.0–46.3) years and males 35.5 (32.6–38.0) years. We found that birth type (wild-born or captive-born) did not influence survival patterns in either population, but there were differential effects of sex on longevity. In the America population, males had higher mortality rates than females, whereas in the Japan population we found no differences between the sexes. First year mortality did not differ between populations for males (18–20%), but for females it was lower in America (15%) compared to Japan (25%). Survival patterns of chimpanzees in the present study will be useful for future investigation into potential causes of regional differences and cross-species comparisons.

Prevalence of antibodies against human respiratory viruses potentially involving anthropozoonoses in wild bonobos

One of the current threats to the bonobo (Pan paniscus), a highly endangered ape species only found in the Democratic Republic of the Congo, are anthropozoonoses caused by human respiratory viruses. To date, epidemiological information regarding respiratory viral infections in bonobos is limited. In this study, we examined fecal immunoglobulin A antibodies against human respiratory viruses in bonobos, which may help estimating the viral prevalence. A substantial proportion of bonobos were positive for the antiviral antibodies, including those against parainfluenza virus, respiratory syncytial virus, influenza virus, rhinovirus, and mumps virus. The prevalence of the antibodies was found to depend on the viral species and bonobo populations, suggesting that the bonobos had been exposed to these respiratory viruses. These results may indicate the need for an epidemiological evidence-based action plan for the protection of bonobos from anthropozoonoses.

Identification of Escherichia coli and Related Enterobacteriaceae and Examination of Their Phenotypic Antimicrobial Resistance Patterns: A Pilot Study at A Wildlife-Livestock Interface in Lusaka, Zambia

A cross-sectional study was used to identify and assess prevalence and phenotypic antimicrobial resistance (AMR) profiles of Escherichia coli and other enterobacteria isolated from healthy wildlife and livestock cohabiting at a 10,000 acres game ranch near Lusaka, Zambia. Purposive sampling was used to select wildlife and livestock based on similarities in behavior, grazing habits and close interactions with humans. Isolates (n = 66) from fecal samples collected between April and August 2018 (n = 84) were examined following modified protocols for bacteria isolation, biochemical identification, molecular detection, phylogenetic analysis, and antimicrobial susceptibility testing by disc diffusion method. Data were analyzed using R software, Genetyx ver.12 and Mega 6. Using Applied Profile Index 20E kit for biochemical identification, polymerase chain reaction assay and sequencing, sixty-six isolates were identified to species level, of which Escherichia coli (72.7%, 48/66), E. fergusonii (1.5%, 1/66), Shigella sonnei (22.7%, 14/66), Sh. flexinerri (1.5%, 1/66) and Enterobacteriaceae bacterium (1.5%, 1/66), and their relationships were illustrated in a phylogenetic tree. Phenotypic antimicrobial resistance or intermediate sensitivity expression to at least one antimicrobial agent was detected in 89.6% of the E. coli, and 73.3% of the Shigella isolates. The E. coli isolates exhibited the highest resistance rates to ampicillin (27%), ceftazidime (14.3%), cefotaxime (9.5%), and kanamycin (9.5%). Multidrug resistance (MDR) was detected in 18.8% of E. coli isolates while only 13.3% Shigella isolates showed MDR. The MDR was detected among isolates from impala and ostrich (wild animals in which no antimicrobial treatment was used), and in isolates from cattle, pigs, and goats (domesticated animals). This study indicates the possible transmission of drug-resistant microorganisms between animals cohabiting at the wildlife–livestock interface. It emphasizes the need for further investigation of the role of wildlife in the development and transmission of AMR, which is an issue of global concern.

Human Respiratory Syncytial Virus Detected in Mountain Gorilla Respiratory Outbreaks

Respiratory illness (RI) accounts for a large proportion of mortalities in mountain gorillas (Gorilla beringei beringei), and fatal outbreaks, including disease caused by human metapneumovirus (HMPV) infections, have heightened concern about the risk of human pathogen transmission to this endangered species, which is not only critically important to the biodiversity of its ecosystem but also to the economies of the surrounding human communities. Our goal was to conduct a molecular epidemiologic study to detect the presence of HRSV and HMPV in fecal samples from wild human-habituated free-ranging mountain gorillas in Rwanda and to evaluate the role of these viruses in RI outbreaks. Fecal samples were collected from gorillas with clinical signs of RI between June 2012 and February 2013 and tested by real-time and conventional polymerase chain reaction (PCR) assays; comparison fecal samples were obtained from gorillas without clinical signs of RI sampled during the 2010 Virunga gorilla population census. PCR assays detected HMPV and HRSV first in spiked samples; subsequently, HRSV-A, the worldwide-circulating ON1 genotype, was detected in 12 of 20 mountain gorilla fecal samples collected from gorillas with RI during outbreaks, but not in samples from animals without respiratory illness. Our findings confirmed that pathogenic human respiratory viruses are transmitted to gorillas and that they are repeatedly introduced into mountain gorilla populations from people, attesting to the need for stringent biosecurity measures for the protection of gorilla health.

Molecular characterization of nodule worm in a community of Bornean primates

Strongyles are commonly reported parasites in studies of primate parasite biodiversity. Among them, nodule worm species are often overlooked as a serious concern despite having been observed to cause serious disease in nonhuman primates and humans. In this study, we investigated whether strongyles found in Bornean primates are the nodule worm Oesophagostomum spp., and to what extent these parasites are shared among members of the community. To test this, we propose two hypotheses that use the parasite genetic structure to infer transmission processes within the community. In the first scenario, the absence of parasite genetic substructuring would reflect high levels of parasite transmission among primate hosts, as primates' home ranges overlap in the study area. In the second scenario, the presence of parasite substructuring would suggest cryptic diversity within the parasite genus and the existence of phylogenetic barriers to cross-species transmission. By using molecular markers, we identify strongyles infecting this primate community as O. aculeatum, the only species of nodule worm currently known to infect Asian nonhuman primates. Furthermore, the little to no genetic substructuring supports a scenario with no phylogenetic barriers to transmission and where host movements across the landscape would enable gene flow between host populations. This work shows that the parasite's high adaptability could act as a buffer against local parasite extinctions. Surveys targeting human populations living in close proximity to nonhuman primates could help clarify whether this species of nodule worm presents the zoonotic potential found in the other two species infecting African nonhuman primates.

Marmota himalayana in the Qinghai-Tibetan plateau as a special host for bi-segmented and unsegmented picobirnaviruses

Wildlife has been considered the main source of novel viruses causing emerging infectious diseases. Marmota himalayana is endemic to the Qinghai–Tibetan Plateau, China. Here, based on a high-throughput method using Illumina RNA sequencing, we studied the RNA virome of M. himalayana and discovered multiple novel viruses, especially picobirnaviruses (PBVs), which have a bi-segmented genome and belong to the family Picobirnaviridae. A total of 63% of the viral contigs corresponded to PBVs, comprising 274 segment 1 and 56 segment 2 sequences. Unexpectedly, four unsegmented PBV genomes were also detected and confirmed by PCR and resequencing. According to the phylogenetic analysis, the following nine PBV assortment types are proposed: C1:GI, C2:GIV, C4:GI, C4:GV, C5:GI, C7:GI, C8:GIV, C8:GV and C8:GII. We hypothesize a model of segmentation for the PBV genome, mediated by a 6-bp direct repeat sequence, GAAAGG. The model is supported by detection of the segmentation-associated sequence GAAAGG not only in the 5′ untranslated regions of segment 1 (221 in 289) and segment 2 (57 in 80) of bi-segmented PBVs but also in the 5′ untranslated regions and junction sequences between the capsid and RdRp genes of unsegmented PBVs. Therefore, with RNA sequencing, we found an unexpected biodiversity of PBVs in M. himalayana, indicating that M. himalayana is a special host for PBVs. We also proposed a putative model of how bi-segmented PBVs could be converted into unsegmented PBVs, which sheds new light on the processes of RNA virus genome evolution.

Pathogen Transmission from Humans to Great Apes is a Growing Threat to Primate Conservation

All six great ape species are listed as endangered or critically endangered by the IUCN and experiencing decreasing population trends. One of the threats to these non-human primates is the transmission of pathogens from humans. We conducted a literature review on occurrences of pathogen transmission from humans to great apes to highlight this often underappreciated issue. In total, we found 33 individual occurrences of probable or confirmed pathogen transmission from humans to great apes: 23 involved both pathogen and disease transmission, 7 pathogen transmission only, 2 positive antibody titers to zoonotic pathogens, and 1 pathogen transmission with probable disease. Great ape populations were categorized into captive, semi-free-living, and free-living conditions. The majority of occurrences involved chimpanzees (Pan troglodytes) (n = 23) or mountain gorillas (Gorilla beringei beringei) (n = 8). These findings have implications for conservation efforts and management of endangered great ape populations. Future efforts should focus on monitoring and addressing zoonotic pathogen and disease transmission between humans, great ape species, and other taxa to ensure the health of humans, wild and domestic animals, and the ecosystems we share.

First case report of non-human primates (Alouatta clamitans) with the hypervirulent Klebsiella pneumoniae serotype K1 strain ST 23: A possible emerging wildlife pathogen

BACKGROUND

Hypervirulent strain of Klebsiella pneumoniae genotype K1 isolates have recently emerged, causing severe pyogenic liver abscess complicated by devastating metastatic infections in humans.

METHODS

We describe a short outbreak of the non-human primate (NHP) research center, associated with a hypervirulent K. pneumoniae. The genetic similarity of the strains was evaluated by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) techniques, and virulence encoding genes were detected by polymerase chain reaction (PCR).

RESULTS

The isolates were phenotypically like strains causing community-acquired invasive liver abscess syndrome in humans. All strains exhibited identical PFGE patterns and were found to belong to ST23 and presented a hypermucovisity phenotype and possessed magA and rmpA gene.

CONCLUSION

This is the first case report of NHPs caused by K. pneumoniae displaying a hypermucoviscosity phenotype and belonging to capsular serotypes K1 and ST23.

One Health in China

As a result of rapid economic growth over the previous three decades, China has become the second largest economy worldwide since 2010. However, as a developing country with the largest population, this rapid economic growth primarily based on excessive consumption and waste of resources. Thus, China has been facing particularly severe ecological and environmental problems in speeding up industrialization and urbanization. The impact of the health risk factors is complex and difficult to accurately predict. Therefore, it is critical to investigate potential threats in the context of the human-animal-environment interface to protect human and animal health. The "One Health" concept recognizes that human health is connected to animal and environmental health. This review primarily discusses specific health problems in China, particularly zoonoses, and explains the origin and development of the One Health approach, as well as the importance of a holistic approach in China.

Codetection of Respiratory Syncytial Virus in Habituated Wild Western Lowland Gorillas and Humans During a Respiratory Disease Outbreak

Pneumoviruses have been identified as causative agents in several respiratory disease outbreaks in habituated wild great apes. Based on phylogenetic evidence, transmission from humans is likely. However, the pathogens have never been detected in the local human population prior to or at the same time as an outbreak. Here, we report the first simultaneous detection of a human respiratory syncytial virus (HRSV) infection in western lowland gorillas (Gorilla gorilla gorilla) and in the local human population at a field program in the Central African Republic. A total of 15 gorilla and 15 human fecal samples and 80 human throat swabs were tested for HRSV, human metapneumovirus, and other respiratory viruses. We were able to obtain identical sequences for HRSV A from four gorillas and four humans. In contrast, we did not detect HRSV or any other classic human respiratory virus in gorilla fecal samples in two other outbreaks in the same field program. Enterovirus sequences were detected but the implication of these viruses in the etiology of these outbreaks remains speculative. Our findings of HRSV in wild but human-habituated gorillas underline, once again, the risk of interspecies transmission from humans to endangered great apes.

Epidemiological Surveillance of Lymphocryptovirus Infection in Wild Bonobos

Lymphocryptovirus (LCV) is one of the major gena in the herpesvirus family and is widely disseminated among primates. LCVs of human and rhesus macaques are shown to be causative agents of a number of malignant diseases including lymphoma and carcinoma. Bonobos (Pan paniscus) are highly endangered and the least studied species of the great apes. Considering the potential pathogenicity of the LCV that might threaten the fate of wild bonobos, population-based epidemiological information in terms of LCV prevalence in different location of Bonobo’s habitats will help propose improved conservation strategies for the bonobos. However, such data are not available yet because it is very difficult to collect blood samples in the wild and thus virtually impossible to conduct sero-epidemiological study on the wild ape. In order to overcome this issue, we focused on evaluating anti-LCV IgA in the feces of bonobos, which are available in a non-invasive manner. Preliminary study showed that anti-LCV IgA but not IgG was efficiently and reproducibly detected in the feces of captive chimpanzees. It is noteworthy that the fecal IgA-positive individuals were seropositive for both anti-LCV IgG and IgA and that the IgA antibodies in both sera and feces were also detectable by Western blotting assay. These results indicate that the detection of fecal anti-LCV IgA is likely a reliable and feasible for epidemiological surveillance of LCV prevalence in the great apes. We then applied this method and found that 31% of wild bonobos tested were positive for anti-LCV IgA antibody in the feces. Notably, the positivity rates varied extensively among their sampled populations. In conclusion, our results in this study demonstrate that LCV is highly disseminated among wild bonobos while the prevalence is remarkably diverse in their population-dependent manner.

Detection and characterization of zoonotic pathogens of free-ranging non-human primates from Zambia

Background

Wildlife may harbor infectious pathogens that are of zoonotic concern acting as a reservoir of diseases transmissible to humans and domestic animals. This is due to human-wildlife conflicts that have become more frequent and severe over recent decades, competition for the available natural habitats and resources leading to increased human encroachment on previously wild and uninhabited areas.

Methods

A total of 88 spleen DNA samples from baboons and vervet monkeys from Zambia were tested for zoonotic pathogens using genus or species-specific PCR. The amplified products were then subjected to sequencing analysis.

Results

We detected three different pathogenic agents, including Anaplasma phagocytophilum in 12 samples (13.6%), Rickettsia spp. in 35 samples (39.8%) and Babesia spp. in 2 samples (2.3%).

Conclusion

The continuously increasing contacts between humans and primate populations raise concerns about transmission of pathogens between these groups. Therefore, increased medical and public awareness and public health surveillance support will be required to detect and control infections caused by these agents at the interface between humans and wildlife.

Retrospective serology study of respiratory virus infections in captive great apes

Great apes are extremely sensitive to infections with human respiratory viruses. In this study, we retrospectively analyzed sera from captive chimpanzees, gorillas and orang-utans. More than 1000 sera (403 chimpanzee, 77 gorilla, and 535 orang-utan sera) were analyzed for antibodies to the human respiratory viruses RSV (respiratory syncytial virus, hMPV (human metapneumovirus), H1N1 and H3N2 influenza A viruses, and influenza B virus. In all ape species high seroprevalences were found for RSV, hMPV, and influenza B virus. A high percentage of captive chimpanzees also showed evidence of influenza A H1N1 infections, and had low levels of H3N2 antibodies, while in sera from gorillas and orang-utans antibody levels to influenza A and B viruses were much lower or practically absent. Transmission of respiratory viruses was examined in longitudinal sera of young chimpanzees, and in chimpanzee sera taken during health checks. In young animals isolated cases of influenza infections were monitored, but evidence was found for single introductions followed by a rapid dissemination of RSV and hMPV within the group. Implementation of strict guidelines for handling and housing of nonhuman primates was shown to be an efficient method to reduce the introduction of respiratory infections in colonies of captive animals. RSV seroprevalence rates of chimpanzees remained high, probably due to circulating virus in the chimpanzee colony.

Field immobilization for treatment of an unknown illness in a wild chimpanzee (Pan troglodytes schweinfurthii) at Gombe National Park, Tanzania: findings, challenges, and lessons learned

Infectious diseases are widely presumed to be one of the greatest threats to ape conservation in the wild. Human diseases are of particular concern, and the costs and benefits of human presence in protected areas with apes are regularly debated. While numerous syndromes with fatal outcomes have recently been described, precise identification of pathogens remains difficult. These diagnostic difficulties are compounded by the fact that direct veterinary intervention on wild apes is quite rare. Here we present the unique case of a wild chimpanzee at Gombe National Park that was observed with a severe illness and was subsequently examined and treated in the field. Multiple specimens were collected and tested with the aim of identifying the pathogen responsible for the illness. Our findings represent the first extensive screening of a living wild chimpanzee, yet despite our efforts, the cause and source of illness remain unknown. Nevertheless, our findings represent valuable baseline data for the ape conservation community and for comparison with other recent findings. In addition, we present the case here to demonstrate the planning required and multiple types of expertise necessary to maximize the amount of data obtained from such a rare intervention, and to provide lessons learned for future studies.

Distribution of Streptococcus troglodytae and Streptococcus dentirousetti in chimpanzee oral cavities

The aim of this study was to analyze the distribution and phenotypic properties of the indigenous streptococci in chimpanzee (Pan troglodytes) oral cavities. Eleven chimpanzees (aged from 9 to 44 years, mean ± SD, 26.9 ± 12.6 years) in the Primate Research Institute of Kyoto University were enrolled in this research and brushing bacterial samples collected from them. Streptococci were isolated from the oral cavities of all chimpanzees. The isolates (n = 46) were identified as thirteen species by 16S rRNA genes analysis. The predominant species was Streptococcus sanguinis of mitis streptococci from five chimpanzees (45%). Mutans streptococci were isolated from six chimpanzees (55%). The predominant species in the mutans streptococci were Streptococcus troglodytae from four chimpanzees (36%), this species having been proposed as a novel species by us, and Streptococcus dentirousetti from three chimpanzees (27%). Streptococcus mutans was isolated from one chimpanzee (9%). However, Streptococcus sobrinus, Streptococcus macacae and Streptococcus downei, which are indigenous to human and monkey (Macaca fasciclaris) oral habitats, were not isolated. Of the mutans streptococci, S. troglodytae, S. dentirousetti, and S. mutans possessed strong adherence activity to glass surface.

Parasite zoonoses and wildlife: One Health, spillover and human activity

This review examines parasite zoonoses and wildlife in the context of the One Health triad that encompasses humans, domestic animals, wildlife and the changing ecosystems in which they live. Human (anthropogenic) activities influence the flow of all parasite infections within the One Health triad and the nature and impact of resulting spillover events are examined. Examples of spillover from wildlife to humans and/or domestic animals, and vice versa, are discussed, as well as emerging issues, particularly the need for parasite surveillance of wildlife populations. Emphasis is given to Trypanosoma cruzi and related species in Australian wildlife, Trichinella, Echinococcus, Giardia, Baylisascaris, Toxoplasma and Leishmania.