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The endangered mountain gorilla (Gorilla beringei beringei) in Rwanda, Uganda, and the Democratic Republic of Congo is frequently in contact with humans through tourism, research activities, and illegal entry of people into protected gorilla habitat. Herpesviruses, which are ubiquitous in primates, have the potential to be shared in any setting where humans and gorillas share habitat. Based on serological findings and clinical observations of orofacial ulcerated lesions resembling herpetic lesions, an alpha-herpesvirus resembling human herpes simplex virus type 1 (HSV-1) has long been suspected to be present in human-habituated mountain gorillas in the wild. While the etiology of orofacial lesions in the wild has not been confirmed, HSV-1 has been suspected in captively-housed mountain gorillas and confirmed in a co-housed confiscated Grauer's gorilla (Gorilla beringei graueri). To better characterize herpesviruses infecting mountain gorillas and to determine the presence/absence of HSV-1 in the free-living population, we conducted a population-wide survey to test for the presence of orally shed herpesviruses. DNA was extracted from discarded chewed plants collected from 294 individuals from 26 groups, and samples were screened by polymerase chain reaction using pan-herpesvirus and HSV-1-specific assays. We found no evidence that human herpesviruses had infected free-ranging mountain gorillas. However, we found gorilla-specific homologs to human herpesviruses, including cytomegaloviruses (GbbCMV-1 and 2), a lymphocryptovirus (GbbLCV-1), and a new rhadinovirus (GbbRHV-1) with similar characteristics (i.e., timing of primary infection, shedding in multiple age groups, and potential modes of transmission) to their human counterparts, human cytomegalovirus, Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, respectively.

Mountain gorillas are particularly inbred compared to other gorillas and even the most inbred human populations. As mountain gorilla skeletal material accumulated during the 1970s, researchers noted their pronounced facial asymmetry and hypothesized that it reflects a population-wide chewing side preference. However, asymmetry has also been linked to environmental and genetic stress in experimental models. Here, we examine facial asymmetry in 114 crania from three Gorilla subspecies using 3D geometric morphometrics. We measure fluctuating asymmetry (FA), defined as random deviations from perfect symmetry, and population-specific patterns of directional asymmetry (DA). Mountain gorillas, with a current population size of about 1000 individuals, have the highest degree of facial FA (explaining 17% of total facial shape variation), followed by Grauer gorillas (9%) and western lowland gorillas (6%), despite the latter experiencing the greatest ecological and dietary variability. DA, while significant in all three taxa, explains relatively less shape variation than FA does. Facial asymmetry correlates neither with tooth wear asymmetry nor increases with age in a mountain gorilla subsample, undermining the hypothesis that facial asymmetry is driven by chewing side preference. An examination of temporal trends shows that stress-induced developmental instability has increased over the last 100 years in these endangered apes.

BackgroundHuman and filovirus host interactions remain poorly understood in areas where Ebola hemorrhagic fever outbreaks are likely to occur. In the Bwindi region of Uganda, a hot spot of mammalian biodiversity in Africa, human livelihoods are intimately connected with wildlife, creating potential for exposure to filoviruses.MethodsWe tested samples from 331 febrile patients presenting to healthcare facilities near Bwindi Impenetrable Forest, Uganda, by polymerase chain reaction (PCR) analysis and Western blot, using recombinant glycoprotein antigens for Ebola virus (EBOV), Sudan virus (SUDV), Bundibugyo virus (BDBV), and Marburg virus. Behavioral data on contact with wildlife were collected to examine risk factors for filovirus seropositivity.ResultsAll patients were negative for active filovirus infection, by PCR analysis. However, patients were seroreactive to SUDV (4.7%), EBOV (5.3%), and BDBV (8.9%), indicating previous exposure. Touching duikers was the most significant risk factor associated with EBOV seropositivity, while hunting primates and touching and/or eating cane rats were significant risk factors for SUDV seropositivity.ConclusionsPeople in southwestern Uganda have suspected previous exposure to filoviruses, particularly those with a history of wildlife contact. Circulation of filoviruses in wild animals and subsequent spillover into humans could be more common than previously reported.

Free-ranging nonhuman primates are frequent sources of zoonotic pathogens due to their physiologic similarity and in many tropical regions, close contact with humans. Many high-risk disease transmission interfaces have not been monitored for zoonotic pathogens due to difficulties inherent to invasive sampling of free-ranging wildlife. Non-invasive surveillance of nonhuman primates for pathogens with high potential for spillover into humans is therefore critical for understanding disease ecology of existing zoonotic pathogen burdens and identifying communities where zoonotic diseases are likely to emerge in the future. We developed a non-invasive oral sampling technique using ropes distributed to nonhuman primates to target viruses shed in the oral cavity, which through bite wounds and discarded food, could be transmitted to people. Optimization was performed by testing paired rope and oral swabs from laboratory colony rhesus macaques for rhesus cytomegalovirus (RhCMV) and simian foamy virus (SFV) and implementing the technique with free-ranging terrestrial and arboreal nonhuman primate species in Uganda and Nepal. Both ubiquitous DNA and RNA viruses, RhCMV and SFV, were detected in oral samples collected from ropes distributed to laboratory colony macaques and SFV was detected in free-ranging macaques and olive baboons. Our study describes a technique that can be used for disease surveillance in free-ranging nonhuman primates and, potentially, other wildlife species when invasive sampling techniques may not be feasible.

The bacterial diversity in fecal samples of a wild gorilla is described by using a 16S rRNA gene clone library and terminal-restriction fragment length polymorphism (T-RFLP). The results have indicated that fecal populations did not change temporarily, as examined by T-RFLP.

A study was conducted on Asian freshwater clams exposed to water contaminated with infectious Cryptosporidium parvum oocysts. No oocysts were detected in the water 24 hours after the contamination event. The percentage of oocyst-containing clams varied from 20 to 100%, depending on the type of tissue examined and the technique used. Positive samples were obtained when gills and gastrointestinal tracts were processed with immunofluorescent antibody. Clam-released oocysts were surrounded by feces, no free oocysts or oocysts dissociated from fecal matter were observed.

Cryptosporidium parvum oocysts obtained from the feces of Peking ducks, innoculated with the oocysts, produces severe infection in neonatal mice. Histological sections of the ducks fail to reveal life-cycle stages of the cryptosporidia. The number of oocyst shells in the feces is less than that of intact oocysts. The number of intact oocyst shells decreases from day two to day five post inoculation. This indicates that the viability and infectivity of the oocysts is unaffected by passage through the duck's intestine.

The in vitro interaction of Asian freshwater clam or Corbicula fluminea hemocytes and Cryptosporidium parvum oocycsts were examined to determine the interactions occurring between them. Results reveal that waterborne oocysts of Cryptosporidium are filtered from water by C. fluminea and are phagocytosed by hemocytes. Environmental factors affect the recovery and phygocytosis of particles and the kinetics of phagocytosis shown in vitro differ from each other.

The article discusses the roles of Mountain Gorilla Veterinary Program (MGVP), a non-profit veterinary health organization. The main aim of the organization is to minimize the risks and to increase the benefits of the research to the great apes.

The comparison of the brain structure of mountain gorillas (Gorilla beringei beringei) with other great apes is presented. 3 mountain gorilla brains were obtained with a 3T scanner and the volume of neuroanatomical structures were measured and it was found that the brain structure of great apes differ mostly in the sizes of the striatum, cerebellum, and hippocampus.