Molecular characterization of Cryptosporidium species at the wildlife/livestock interface of the Kruger National Park, South Africa

Assessment of domestic pig-bushpig (Potamochoerus larvatus) interactions through local knowledge in rural areas of Madagascar

In many parts of the world, domestic and wild animal populations interact at the interface between natural and agricultural ecosystems. Introduced with the first inhabitants arriving from eastern Africa, the bushpig (Potamochoerus larvatus) is the largest living terrestrial mammal in Madagascar. Bushpigs are regularly reported close to human settlements where they damage crops and gardens. As domestic pigs are often raised in free-ranging conditions around the villages, bushpigs and domestic pigs can interact leading to the transmission and circulation of shared swine pathogens that impact both animal and human health. In this study, we characterized the socio-ecological context of bushpig-domestic pig interactions in two different regions of western Madagascar. We conducted participatory mapping sessions and focus group interviews with 65 hunters, 80 pig farmers and 96 crop farmers in 20 fokontany, the smallest administrative unit in Madagascar. After discussing with participants, we gathered information about the spatialization of interactions and their potential geographical drivers. We explored data by performing multiple correspondence analysis and hierarchical clustering on principal components. Based on the reported occurrence or absence of bushpig-domestic pig interactions we were able to classify areas with high or intermediate levels of interactions or no interactions at all. Interactions between the two pig species were reported in only 25% of the fokontany assessed. Even though both suid species were attracted to fruit trees, crops, and water sources, only indirect interactions in those spots were reported. Direct interactions were reported in 10% of cases and referred to interspecific sexual and/or agonistic behavior. The participatory methods used to acquire local knowledge about natural events were confirmed as valuable, low-cost exploratory methods to characterize areas with wild-domestic animal interactions. The results of this study will help plan future studies to characterize the interface between the two species from an ecological or epidemiological perspective using more sensitive and sophisticated ecological approaches.

The microscopic five of the big five: Managing zoonotic diseases within and beyond African wildlife protected areas

African protected areas strive to conserve the continent's great biodiversity with a targeted focus on the flagship 'Big Five' megafauna. Though often not considered, this biodiversity protection also extends to the lesser-known microbes and parasites that are maintained in these diverse ecosystems, often in a silent and endemically stable state. Climate and anthropogenic change, and associated diversity loss, however, are altering these dynamics leading to shifts in ecological interactions and pathogen spill over into new niches and hosts. As many African protected areas are bordered by game and livestock farms, as well as villages, they provide an ideal study system to assess infection dynamics at the human-livestock-wildlife interface. Here we review five zoonotic, multi-host diseases (bovine tuberculosis, brucellosis, Rift Valley fever, schistosomiasis and cryptosporidiosis)-the 'Microscopic Five'-and discuss the biotic and abiotic drivers of parasite transmission using the iconic Kruger National Park, South Africa, as a case study. We identify knowledge gaps regarding the impact of the 'Microscopic Five' on wildlife within parks and highlight the need for more empirical data, particularly for neglected (schistosomiasis) and newly emerging (cryptosporidiosis) diseases, as well as zoonotic disease risk from the rising bush meat trade and game farm industry. As protected areas strive to become further embedded in the socio-economic systems that surround them, providing benefits to local communities, One Health approaches can help maintain the ecological integrity of ecosystems, while protecting local communities and economies from the negative impacts of disease.

Bushpig (Potamochoerus larvatus) Hunting in Rural Areas of Madagascar and Its Health and Socioeconomic Implications

Bushmeat consumption and trade plays a relevant role in many tropical countries as a source of protein and income for rural populations. In Madagascar, rural populations depend heavily on natural resources and wildlife as source of income and protein. The bushpig (Potamochoerus larvatus) is the largest mammal available in the island and regularly hunted. However, little is known about the importance and characteristics of this activity and its implication as a potential source of pathogens for both humans and domestic animals. A cross-sectional study was conducted in 2014–2015 in five different regions of rural Madagascar suspected to have significant bushpig populations to (i) quantify and characterize the importance of bushpig hunting, (ii) assess the socioeconomic impact of bushpig trade, (iii) evaluate the potential pathogen transmission between bushpigs, domestic pigs and humans. A total of 77 hunters, 10 butchers and 95 pig farmers were individually interviewed. Hunting seasonality and the perception of local hunters with regards to the dynamics of bushpig populations in the last decade differed between the tropical dry and tropical sub-arid climatic zones. The top reason for hunting bushpigs was crop protection but personal consumption and selling of meat were also common. Hunting efficacy was largely dependent on the technique used. Snares and traps, the most widely used techniques, allowed the majority of hunters to catch from one to 10 bushpigs per year. Limited commercial bushpig trade was observed with only 0.8 bushpig sold in average per year and per hunter, representing a 16 USD income. The average price per kilo sold was USD 0.8 and the average profit received by each butcher/collector after the sale of a carcass was USD 11.9. No perception of disease risks nor precautions were taken to prevent potential pathogen transmission from bushpig to humans or pigs. Most of the hunters (68%) indicated that they had never seen a diseased bushpig. Bushpig hunting in our study areas in Madagascar was basically a small-scale subsistence hunting, very different from commercial bushmeat hunting described in areas of Central Africa or the Amazon Basin. More research is needed to verify the sustainability of bushpig hunting and its potential role in terms of reducing pressure on other endemic wildlife species and transmitting pathogens to humans and pigs.

Association of Common Zoonotic Pathogens With Concentrated Animal Feeding Operations

Animal farming has intensified significantly in recent decades, with the emergence of concentrated animal feeding operations (CAFOs) in industrialized nations. The congregation of susceptible animals in CAFOs can lead to heavy environmental contamination with pathogens, promoting the emergence of hyper-transmissible, and virulent pathogens. As a result, CAFOs have been associated with emergence of highly pathogenic avian influenza viruses, hepatitis E virus, Escherichia coli O157:H7, Streptococcus suis, livestock-associated methicillin-resistant Staphylococcus aureus, and Cryptosporidium parvum in farm animals. This has led to increased transmission of zoonotic pathogens in humans and changes in disease patterns in general communities. They are exemplified by the common occurrence of outbreaks of illnesses through direct and indirect contact with farm animals, and wide occurrence of similar serotypes or subtypes in both humans and farm animals in industrialized nations. Therefore, control measures should be developed to slow down the dispersal of zoonotic pathogens associated with CAFOs and prevent the emergence of new pathogens of epidemic and pandemic potential.

High Prevalence of Cryptosporidium meleagridis in Domestic Pigeons (Columba livia domestica) Raises a Prospect of Zoonotic Transmission in Babylon Province, Iraq

Cryptosporidium is one of the most common protozoan’s parasites with remarkable infectivity of a wide range of animals, including mammals and birds. Domestic pigeons (Columba livia domestica) act as a potential reservoir for several species of Cryptosporidium because they live in close proximity to humans. This study was conducted to assess the genetic diversity of Cryptosporidium in domestic pigeons in Iraq. A total of one hundred samples obtained from feces of domestic pigeons in Babylon province were included. After being exposed to microbial examination, all fecal samples were subsequently screened by nested polymerase chain reaction (PCR) for the possible recognition of Cryptosporidium species. Microscopy tests detected only 14/100 (14%) of infection with Cryptosporidium, while molecular tests detected 21/100 (21%) of the same targeted parasite. Sequencing experiments showed a high prevalence of C. meleagridis with 13/21 (61.90%), followed by C. baileyi with 7/21 (33.33%), while only one infection was detected with C. hominis (1/21) (4.76%). No co-infection with mixed Cryptosporidium spp. was observed, and sex factor was not found to affect the infection rate. In conclusion, this study informed a high prevalence of C. meleagridis in domestic pigeons than both C. baileyi and C. hominis, respectively, signifying a higher zoonotic potential of C. meleagridis between domestic pigeons and their handlers. This finding may raise more questions with regard to the increasing infectivity of C. meleagridis in human. This is the first important screening study in Iraq that uses molecular methods for the detection of Cryptosporidium in domesticated pigeons.

A review of pathological findings in impalas (Aepyceros melampus) in South Africa

Impalas (Aepyceros melampus) are common African antelope. A retrospective study was conducted of 251 impala cases from game farms, national parks and zoos submitted by veterinarians and pathologists in South Africa (2003-2016). Histopathology slides as well as records of macroscopic lesions and additional diagnostic tests performed were examined. Non-infectious conditions, such as acute pulmonary congestion and oedema, cachexia, traumatic injury and anaesthetic-related mortality were the most common causes of morbidity and mortality. Bacterial sepsis was the most common infectious disease, whilst skeletal muscle and myocardial sarcocystosis and verminous cholangitis and pneumonia were the most common parasitic diseases. Although the retrospective nature of this study limits the significance of the relative prevalence of lesions in the three locations, management decisions and diagnostic plans may be informed by the results. Impala from game farms had significantly more cachexia cases than those from other locations. Impala from zoos had significantly more lymphoid depletion than those from other locations. These findings suggest that nutrition and pasture management, enclosure design, management of intra- and interspecies aggression and improved anaesthetic protocols could improve animal welfare and survival of impala on game farms and in zoos. This report presents a detailed survey of diseases and conditions found in impala that provides baseline data for veterinary pathologists.

Cryptosporidium infections in terrestrial ungulates with focus on livestock: a systematic review and meta-analysis

Background

Cryptosporidium spp. are causative agents of gastrointestinal diseases in a wide variety of vertebrate hosts. Mortality resulting from the disease is low in livestock, although severe cryptosporidiosis has been associated with fatality in young animals.

Methods

The goal of this systematic review and meta-analysis was to review the prevalence and molecular data on Cryptosporidium infections in selected terrestrial domestic and wild ungulates of the families Bovidae (bison, buffalo, cattle, goat, impala, mouflon sheep, sheep, yak), Cervidae (red deer, roe deer, white-tailed deer), Camelidae (alpaca, camel), Suidae (boar, pig), Giraffidae (giraffes) and Equidae (horses). Data collection was carried out using PubMed, Scopus, Science Direct and Cochran databases, with 429 papers being included in this systematic analysis.

Results

The results show that overall 18.9% of ungulates from the investigated species were infected with Cryptosporidium spp. Considering livestock species (cattle, sheep, goats, pigs, horses and buffaloes), analysis revealed higher Cryptosporidium infection prevalence in ungulates of the Cetartiodactyla than in those of the Perissodactyla, with cattle (29%) being the most commonly infected farm animal.

Conclusions

Overall, the investigated domestic ungulates are considered potential sources of Cryptosporidium contamination in the environment. Control measures should be developed to reduce the occurrence of Cryptosporidium infection in these animals. Furthermore, literature on wild populations of the named ungulate species revealed a widespread presence and potential reservoir function of wildlife.

A review of wildlife tourism and meta-analysis of parasitism in Africa's national parks and game reserves

The recent increase of parasitic diseases associated with wildlife tourism can be traced to human contact with wildlife and intense modification of wildlife habitat. The continental estimates of parasitic diseases among visited wildlife-tourists and mammalian wildlife present in conservation areas are lacking; therefore, a general review was necessary to provide insights into Africa's parasitic disease burden and transmission between humans and wildlife. A two-step analysis was conducted with searches in Ovid MEDLINE, EMBASE, PubMed, Web of Science and Global Health. All diseases reported without prevalence were grouped and analysed as categorical data while meta-analysis of prevalence rates of parasitic diseases in wildlife from national parks and reserves in Africa was conducted. Only 4.7% of the tourist centres reported routine wildlife diagnosis for parasitic diseases. Disease intensity shows that cryptosporidiosis and seven other parasitic diseases were observed in both human and wildlife; however, no significant difference in intensity between human and wildlife hosts was observed. Schistosomiasis intensity reports showed a significant increase (P < 0.05) while entamoebiasis showed a significant decrease (P < 0.05) in humans as compared to wildlife. Visiting tourists were more infected with malaria, while wildlife was more infected with parasitic gastroenteritis (PGE). The meta-analysis of wildlife revealed the highest prevalence of PGE with mixed parasites and lowest prevalence of Giardia spp. at 99.9 and 5.7%, respectively. The zoonotic and socioeconomic impact of some of these parasites could pose a severe public threat to tourism. Pre- and post-travel clinical examinations are important for tourists while routine examination, treatment and rational surveillance are important for these animals to improve wildlife tourism.

The Occurrence of Some Nonblood Protozoan Parasites in Wild and Domestic Mammals in South Africa

Relatively little is known about protozoan parasites in African animals. Here we investigated the occurrence of protozoan parasites in mammals from South Africa. Oocysts of protozoan parasites were detected in 13 of 56 (23%) fecal samples using conventional microscopic examination methods. Cryptosporidium spp. and Cystoisospora spp. were detected in eight (14%) and five (9%) samples, respectively. Mixed parasitic infection of Cryptosporidium spp. and Cystoisospora spp. was recorded in banded mongoose ( Mungos mungo). Cryptosporidium spp. was detected for the first time in cheetah ( Acinonyx jubatus), spotted hyena ( Crocuta crocuta), and African polecat ( Ictonyx striatus). Antibodies to Toxoplasma gondii and Neospora caninum were not detected by enzyme-linked immunosorbent assay in any of 32 sera tested. We detected T. gondii by PCR in tissues of five of 243 (2%) animals: domestic dog ( Canis lupus familiaris), gerbil ( Gerbilliscus spp.), greater kudu ( Tragelaphus strepsiceros), honey badger ( Mellivora capensis), and white-tailed mongoose ( Ichneumia albicauda). Our isolation of T. gondii from white-tailed mongoose and honey badger was a unique finding. All tissue samples were negative for N. caninum. The study increases our knowledge on the occurrence of protozoan parasites in populations of wild and domestic animals in South Africa.

Cryptosporidium and Giardia in Africa: current and future challenges

Cryptosporidium and Giardia are important causes of diarrhoeal illness. Adequate knowledge of the molecular diversity and geographical distribution of these parasites and the environmental and climatic variables that influence their prevalence is important for effective control of infection in at-risk populations, yet relatively little is known about the epidemiology of these parasites in Africa. Cryptosporidium is associated with moderate to severe diarrhoea and increased mortality in African countries and both parasites negatively affect child growth and development. Malnutrition and HIV status are also important contributors to the prevalence of Cryptosporidium and Giardia in African countries. Molecular typing of both parasites in humans, domestic animals and wildlife to date indicates a complex picture of both anthroponotic, zoonotic and spill-back transmission cycles that requires further investigation. For Cryptosporidium, the only available drug (nitazoxanide) is ineffective in HIV and malnourished individuals and therefore more effective drugs are a high priority. Several classes of drugs with good efficacy exist for Giardia, but dosing regimens are suboptimal and emerging resistance threatens clinical utility. Climate change and population growth are also predicted to increase both malnutrition and the prevalence of these parasites in water sources. Dedicated and co-ordinated commitments from African governments involving "One Health" initiatives with multidisciplinary teams of veterinarians, medical workers, relevant government authorities, and public health specialists working together are essential to control and prevent the burden of disease caused by these parasites.

Prevalence and risk factors for cryptosporidiosis: a global, emerging, neglected zoonosis

Background

Cryptosporidiosis is a zoonotic disease caused by the important parasitic diarrheal agent Cryptosporidium spp. Cryptosporidiosis occurs in all classes of animals and man with a rapidly expanding host range and increased importance since the occurrence of human immunodeficiency virus/acquired immunodeficiency syndrome in man.

Objectives

To review the global picture of cryptosporidiosis in man and animals with emphasis on prevalence and risk factors.

Methods

Current relevant literature on cryptosporidiosis was reviewed.

Results

Cryptosporidiosis is widely distributed and the risk factors vary from one region to another with hygiene and immune status as important risk factors.

Conclusions

Cryptosporidium spp. associated mortality has not only been reported in immune-compromised patients, but also in immune-competent patients. Yet in many countries not much attention is paid to the control and prevention of this infection in animals and man. The neglect of this disease despite the serious threat it poses to animals, their husbandry, and humans, has led the World Health Organization to list it among globally neglected diseases. To control and prevent this infection more effort needs to be directed at controlling the risk factors of the infection in man and animals.

Cryptosporidium genotypes in children and calves living at the wildlife or livestock interface of the Kruger National Park, South Africa

Cryptosporidium infection is one of the most common causes of parasitic diarrhoea worldwide in cattle and humans. In developing countries, human cryptosporidiosis is most prevalent during early childhood and links between zoonotic infection and animal related activities have been demonstrated. This study investigated the prevalence and species/genotype distribution of Cryptosporidium among children (< 5 years) and calves (< 6 months) living in a rural farming area adjacent to the Kruger National Park in South Africa, where interactions between humans and wild and domestic animals are known to occur. Cryptosporidium oocysts were detected in 8/143 stool samples of children recruited within the hospital system (5.6%; 95% CI 2.4%, 10.7%) and in 2/352 faecal samples of calves (0.6%; 95% CI 0.1%, 2.0%) using the modified Ziehl–Neelsen (MZN) staining technique. Microscopy positive samples from children were further analysed by PCR targeting the 18S rRNA gene and identified as Cryptosporidium hominis (3/4) and Cryptosporidium meleagridis (1/4). Regardless of the microscopy outcome, randomly selected samples (n = 36) from calves 0–4 months of age were amplified and sequenced at the 18S rRNA gene using nested PCR. Two calves tested positive (5.6%; 95% CI 1.7%, 18.7%), and revealed the presence of Cryptosporidium parvum and Cryptosporidium bovis. The detection of only two zoonotic species (C. parvum in one calf and C. meleagridis in one child) suggests that zoonotic cryptosporidiosis is not currently widespread in our study area; however, the potential exists for amplification of transmission in an immunocompromised population.

Molecular investigation of Cryptosporidium in small caged pets in northeast China: host specificity and zoonotic implications

This study screened 151 pet-derived fecal specimens randomly collected from four commercial markets in northeast China for the presence of Cryptosporidium by genus-specific nested PCRs of the small subunit rRNA gene. Of these, 14 specimens (9.3 %) from nine species of birds, two types of rodents, and a hedgehog were positive for Cryptosporidium. Sequence analysis on the PCR-positive isolates facilitated identification of three Cryptosporidium species (C. baileyi, C. galli, and C. ubiquitum) and two Cryptosporidium genotypes (ferret genotype and avian genotype V). The study birds were affected predominantly with bird-specific C. baileyi (Atlantic canary, budgerigar, crested myna, rock dove, and silky fowl), C. galli (Chinese hwamei), and Cryptosporidium avian genotype V (Fischer's lovebird and rosy-faced lovebird). Cryptosporidium ferret genotype previously considered rodent-adapted was identified in three specimens from budgerigar, chipmunk, and red squirrel. Two specimens collected from common hill myna and hedgehog were positive for C. ubiquitum. The species of birds that can be colonized by Cryptosporidium were extended. Moreover, the data expanded the host range of Cryptosporidium ferret genotype and C. ubiquitum, especially the birds. The carriage of zoonotic C. ubiquitum in small caged pets is of public health importance.

Transmission of Foot-and-Mouth Disease SAT2 Viruses at the Wildlife-Livestock Interface of Two Major Transfrontier Conservation Areas in Southern Africa

Over a decade ago, foot-and-mouth disease (FMD) re-emerged in Southern Africa specifically in beef exporting countries that had successfully maintained disease-free areas in the past. FMD virus (FMDV) serotype SAT2 has been responsible for a majority of these outbreaks. Epidemiological studies have revealed the importance of the African buffalo as the major wildlife FMD reservoir in the region. We used phylogeographic analysis to study dynamics of FMD transmission between buffalo and domestic cattle at the interface of the major wildlife protected areas in the region currently encompassing two largest Transfrontier conservation areas: Kavango-Zambezi (KAZA) and Great Limpopo (GL). Results of this study showed restricted local occurrence of each FMDV SAT2 topotypes I, II, and III, with occasional virus migration from KAZA to GL. Origins of outbreaks in livestock are frequently attributed to wild buffalo, but our results suggest that transmission from cattle to buffalo also occurs. We used coalescent Bayesian skyline analysis to study the genetic variation of the virus in cattle and buffalo, and discussed the association of these genetic changes in the virus and relevant epidemiological events that occurred in this area. Our results show that the genetic diversity of FMDV SAT2 has decreased in buffalo and cattle population during the last decade. This study contributes to understand the major dynamics of transmission and genetic variation of FMDV SAT2 in Southern Africa, which will could ultimately help in designing efficient strategies for the control of FMD at a local and regional level.

Wild and Domestic Pig Interactions at the Wildlife-Livestock Interface of Murchison Falls National Park, Uganda, and the Potential Association with African Swine Fever Outbreaks

Bushpigs (BPs) (Potamochoerus larvatus) and warthogs (WHs) (Phacochoerus africanus), which are widely distributed in Eastern Africa, are likely to cohabitate in the same environment with domestic pigs (DPs), facilitating the transmission of shared pathogens. However, potential interactions between BP, WH, and DP, and the resulting potential circulation of infectious diseases have rarely been investigated in Africa to date. In order to understand the dynamics of such interactions and the potential influence of human behavior and husbandry practices on them, individual interviews (n = 233) and participatory rural appraisals (n = 11) were carried out among Ugandan pig farmers at the edge of Murchison Falls National Park, northern Uganda. In addition, as an example of possible implications of wild and DP interactions, non-linear multivariate analysis (multiple correspondence analyses) was used to investigate the potential association between the aforementioned factors (interactions and human behavior and practices) and farmer reported African swine fever (ASF) outbreaks. No direct interactions between wild pigs (WPs) and DP were reported in our study area. However, indirect interactions were described by 83 (35.6%) of the participants and were identified to be more common at water sources during the dry season. Equally, eight (3.4%) farmers declared exposing their DP to raw hunting leftovers of WPs. The exploratory analysis performed suggested possible associations between the farmer reported ASF outbreaks and indirect interactions, free-range housing systems, dry season, and having a WH burrow less than 3 km from the household. Our study was useful to gather local knowledge and to identify knowledge gaps about potential interactions between wild and DP in this area. This information could be useful to facilitate the design of future observational studies to better understand the potential transmission of pathogens between wild and DPs.

Transmission of foot and mouth disease at the wildlife/livestock interface of the Kruger National Park, South Africa: Can the risk be mitigated?

In Southern Africa, the African buffalo (Syncerus caffer) is the natural reservoir of foot and mouth disease (FMD). Contacts between this species and cattle are responsible for most of the FMD outbreaks in cattle at the edge of protected areas, which generate huge economic losses. During the late 1980's and 90's, the erection of veterinary cordon fences and the regular vaccination of cattle exposed to buffalo contact at the interface of the Kruger National Park (KNP), proved to be efficient to control and prevent FMD outbreaks in South Africa. However, since 2000, the efficiency of those measures has deteriorated, resulting in an increased rate of FMD outbreaks in cattle outside KNP, currently occurring more than once a year. Based on retrospective ecological and epidemiological data, we developed a stochastic quantitative model to assess the annual risk of FMD virus (FMDV) transmission from buffalo to cattle herds present at the KNP interface. The model suggests that good immunization of approximately 75% of the cattle population combined with a reduction of buffalo/cattle contacts is an efficient combination to reduce FMDV transmission to one infective event every 5.5 years, emulating the epidemiological situation observed at the end of the 20th century, before current failure of control measures. The model also indicates that an increasing number of buffalo present in the KNP and crossing its boundaries, combined with a reduction in the vaccination coverage of cattle herds at the interface, increases 3-fold the risk of transmission (one infective event per year).The model proposed makes biological sense and provides a good representation of current knowledge of FMD ecology and epidemiology in Southern Africa which can be used to discuss with stakeholders on different management options to control FMD at the wildlife livestock interface and updated if new information becomes available. It also suggests that the control of FMD at the KNP interface is becoming increasingly challenging and will probably require alternative approaches to control this disease and its economic impact.

First report of Cryptosporidium species in farmed and wild buffalo from the Northern Territory, Australia

A molecular epidemiological survey of Cryptosporidium from water buffalo (Bubalus bubalis) in the Northern Territory in Australia was conducted. Fecal samples were collected from adult farmed (n = 50) and wild buffalo (n = 50) and screened using an 18S quantitative PCR (qPCR). Positives were typed by sequence analysis of 18S nested PCR products. The qPCR prevalence of Cryptosporidium species in farmed and wild buffalo was 30 and 12 %, respectively. Sequence analysis identified two species: C. parvum and C. bovis, with C. parvum accounting for ~80 % of positives typed from the farmed buffalo fecal samples compared to 50 % for wild buffalo. Subtyping at the 60 kDa glycoprotein (gp60) locus identified C. parvum subtypes IIdA19G1 (n = 4) and IIdA15G1 (n = 1) in the farmed buffalo and IIaA18G3R1 (n = 2) in the wild buffalo. The presence of C. parvum, which commonly infects humans, suggests that water buffaloes may contribute to contamination of rivers and waterways with human infectious Cryptosporidium oocysts, and further research on the epidemiology of Cryptosporidium in buffalo populations in Australia is required.

Public health significance of zoonotic Cryptosporidium species in wildlife: Critical insights into better drinking water management

Cryptosporidium is an enteric parasite that is transmitted via the faecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Human encroachment into natural ecosystems has led to an increase in interactions between humans, domestic animals and wildlife populations. Increasing numbers of zoonotic diseases and spill over/back of zoonotic pathogens is a consequence of this anthropogenic disturbance. Drinking water catchments and water reservoir areas have been at the front line of this conflict as they can be easily contaminated by zoonotic waterborne pathogens. Therefore, the epidemiology of zoonotic species of Cryptosporidium in free-ranging and captive wildlife is of increasing importance. This review focuses on zoonotic Cryptosporidium species reported in global wildlife populations to date, and highlights their significance for public health and the water industry.

History and development of research on wildlife parasites in southern Africa, with emphasis on terrestrial mammals, especially ungulates

The history of wildlife parasitology in South Africa, and to some extent southern Africa, is reviewed, giving a brief overview of the early years and following its development from the founding of the Onderstepoort Veterinary Institute in 1908 until the turn of the century. An emphasis is placed on game species. The main findings on protozoan parasites, including those of carnivores, are presented, starting in the 1890s and leading up to the first decade of the 21st century. Important developments with regard to the studies of arthropod and helminth parasites took place during a period of three decades, starting from the 1970s. Because of the sheer volume of work done by parasitologists during this time, this particular part of the overview concentrates on South African authors or authors working in South Africa at the time, and is limited to hosts that are members of the order Perissodactyla and the superorder Cetartiodactyla.

Long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western Lowland Gorillas (Gorilla gorilla gorilla) at different stages of habituation in Dzanga Sangha Protected Areas, Central African Republic

BACKGROUND

Infectious diseases pose one of the greatest threats to endangered species, and a risk of gastrointestinal parasite transmission from humans to wildlife has always been considered as a major concern of tourism. Increased anthropogenic impact on primate populations may result in general changes in communities of their parasites, and also in a direct exchange of parasites between humans and primates.

AIMS

To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, we conducted a long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western lowland gorillas at different stages of the habituation process, humans, and other wildlife in Dzanga-Sangha Protected Areas in the Central African Republic.

RESULTS

We detected Encephalitozoon cuniculi genotypes I and II (7.5%), Enterocytozoon bieneusi genotype D and three novel genotypes (gorilla 1-3) (4.0%), Giardia intestinalis subgroup A II (2.0%) and Cryptosporidium bovis (0.5%) in gorillas, whereas in humans we found only G. intestinalis subgroup A II (2.1%). In other wild and domestic animals we recorded E. cuniculi genotypes I and II (2.1%), G. intestinalis assemblage E (0.5%) and C. muris TS03 (0.5%).

CONCLUSION

Due to the non-specificity of E. cuniculi genotypes we conclude that detection of the exact source of E. cuniculi infection is problematic. As Giardia intestinalis was recorded primarily in gorilla groups with closer human contact, we suggest that human-gorilla transmission has occurred. We call attention to a potentially negative impact of habituation on selected pathogens which might occur as a result of the more frequent presence of humans in the vicinity of both gorillas under habituation and habituated gorillas, rather than as a consequence of the close contact with humans, which might be a more traditional assumption. We encourage to observe the sections concerning hygiene from the IUCN best practice guidelines for all sites where increased human-gorilla contact occurs.

Operationalizing a One Health approach to global health challenges

The One Health approach, which recognizes the interconnectedness of human, animal and ecosystem health, encourages collaboration between diverse disciplines to address complex health problems. The advantages and challenges posed by these interdisciplinary collaborations are described in this review. Learning networks where diverse participants can openly share processes, best practices, and case studies are discussed as a strategy for conducting transdisciplinary One Health research and tackling complex global health problems. The 11 papers in this special issue are also introduced as they illustrate how a One Health approach can be applied to better understand and control zoonotic pathogens, engage community stakeholders in One Health research and utilize wildlife species, most notably sea otters and birds, as sentinels of ecosystem health. Collaboration is rarely without complications; however, drawing on these insights may benefit the process of operationalizing the One Health approach to address today's global health challenges.