Syndromic Surveillance of Respiratory Disease in Free-Living Chimpanzees

Current practice and future directions in syndromic surveillance for animal health: A scoping review and analysis

Syndromic surveillance, the monitoring of non-specific indicators or symptoms, is a powerful tool for monitoring health or well-being. We conducted a scoping review to provide an up-to-date, global overview of syndromic surveillance for animal health, focusing on variation between animal sectors (livestock, companion, and wildlife), geography, indicators, data providers, and One Health approaches. We searched the Scopus and PubMed databases for articles describing or using data from syndromic surveillance systems or testing the potential of a data set or method for syndromic surveillance and supplemented this information with gray literature to determine further development of systems. We identified 126 syndromic surveillance systems from 165 articles. Most systems (n = 84, 67 %) were in the proof-of-concept phase, while only 25 (20 %) were established operational systems. These were mostly run by governments (n = 15, 58 %), as well as nonprofits (n = 4, 15 %), and academic institutions (n = 3, 12 %). The majority of systems monitored livestock (n = 89, 71 %); just over half were located in Europe (n = 64, 51 %) and a further 28 % (n = 35) in North America. Only eight systems (6 %) monitored multiple animal sectors. Twelve systems (10 %) used a One Health approach, linking data or surveillance concerning the same threat in humans and any animal sector. The most common data collectors were private veterinarians (n = 35, 28 %) and animals' owners (n = 29, 23 %); the most commonly used indicators were mortality (n = 52, 41 %), general illness (n = 36, 29 %), and reproductive symptoms (n = 31, 25 %). While syndromic surveillance for animals continues to develop, there is still a gap between research and implementation. However, even established systems are vulnerable to lack of continued funding and support. By compiling and analyzing this data, we highlight developments in syndromic surveillance for animals as well as differences in practices between sectors and regions of the world.

WITHDRAWN: MHC-B Diversity and Signs of Respiratory Illness in Wild, East African Chimpanzees ( Pan troglodytes schweinfurthii )

bioRxiv has withdrawn this preprint following a formal investigation by the University of New Mexico Office of Research Integrity and Compliance.

Great ape health watch: Enhancing surveillance for emerging infectious diseases in great apes

Infectious diseases have the potential to extirpate populations of great apes. As the interface between humans and great apes expands, zoonoses pose an increasingly severe threat to already endangered great ape populations. Despite recognition of the threat posed by human pathogens to great apes, health monitoring is only conducted for a small fraction of the world's wild great apes (and mostly those that are habituated) meaning that outbreaks of disease often go unrecognized and therefore unmitigated. This lack of surveillance (even in sites where capacity to conduct surveillance is present) is the most significant limiting factor in our ability to quickly detect and respond to emerging infectious diseases in great apes when they first appear. Accordingly, we must create a surveillance system that links disease outbreaks in humans and great apes in time and space, and enables veterinarians, clinicians, conservation managers, national decision makers, and the global health community to respond quickly to these events. Here, we review existing great ape health surveillance programs in African range habitats to identify successes, gaps, and challenges. We use these findings to argue that standardization of surveillance across sites and geographic scales, that monitors primate health in real-time and generates early warnings of disease outbreaks, is an efficient, low-cost step to conserve great ape populations. Such a surveillance program, which we call "Great Ape Health Watch" would lead to long-term improvements in outbreak preparedness, prevention, detection, and response, while generating valuable data for epidemiological research and sustainable conservation planning. Standardized monitoring of great apes would also make it easier to integrate with human surveillance activities. This approach would empower local stakeholders to link wildlife and human health, allowing for near real-time, bidirectional surveillance at the great ape-human interface.

The Gombe Ecosystem Health Project: 16 years of program evolution and lessons learned

Infectious disease outbreaks pose a significant threat to the conservation of chimpanzees (Pan troglodytes) and all threatened nonhuman primates. Characterizing and mitigating these threats to support the sustainability and welfare of wild populations is of the highest priority. In an attempt to understand and mitigate the risk of disease for the chimpanzees of Gombe National Park, Tanzania, we initiated a long-term health-monitoring program in 2004. While the initial focus was to expand the ongoing behavioral research on chimpanzees to include standardized data on clinical signs of health, it soon became evident that the scope of the project would ideally include diagnostic surveillance of pathogens for all primates (including people) and domestic animals, both within and surrounding the National Park. Integration of these data, along with in-depth post-mortem examinations, have allowed us to establish baseline health indicators to inform outbreak response. Here, we describe the development and expansion of the Gombe Ecosystem Health project, review major findings from the research and summarize the challenges and lessons learned over the past 16 years. We also highlight future directions and present the opportunities and challenges that remain when implementing studies of ecosystem health in a complex, multispecies environment.

Urinary Cortisol Increases During a Respiratory Outbreak in Wild Chimpanzees

Abstract: In mammals, the excretion of cortisol can provide energy toward restoring homeostasis and is a major component of the stress response. However, chronically elevated cortisol levels also have suppressive effects on immune function. As mounting an immune response is energetically costly, sick individuals may conserve energy by exhibiting certain sickness behaviors, such as declining activity levels. Due to the complex interplay between immune function and sickness behaviors, endocrinological correlates have received growing attention in the medical community, but so far, this subject was investigated rarely. Furthermore, given the complexities of studying illnesses and immunity in natural settings, correlates of sickness behaviors have yet to be studied in non-human primates in the wild.

Methods: We measured urinary cortisol levels using liquid chromatography–mass spectrometry in a group of wild habituated chimpanzees in Taï National Park, Côte d'Ivoire, before, during, and after a respiratory disease outbreak (main causative pathogen: human respiratory syncytial virus A, with coinfections of Streptococcus pneumoniae). Changes in cortisol levels were then related to urinary neopterin levels, a biomarker of immune system activation.

Results: Urinary cortisol levels were found to be more than 10-fold higher during the outbreak in comparison with levels before and after the outbreak period. Increasing cortisol levels were also associated with increasing neopterin levels. Interestingly, rather atypical patterns in a diurnal decline of cortisol levels were found during infection periods, such that levels remained raised throughout the day.

Conclusion: In conclusion, cortisol increase was related to cellular immune response. Our results suggest that cortisol is a mediator of infectious disease pathogenicity through its impact on the immune system and that wild chimpanzees may be facing energetic stress when sick. By monitoring immune challenges in wild-living animals, our study demonstrates that immune defenses have costs and that these costs are context-specific.