Surveillance of Arboviruses in Primates and Sloths in the Atlantic Forest, Bahia, Brazil.

From 2006 through 2014, we conducted seroepidemiological surveys on non-human primates and sloths to investigate the possible circulation of arboviruses in Bahia Atlantic Forest, Brazil. We collected a total of 196 samples from 103 Leontopithecus chrysomelas, 7 Sapajus xanthosternos, 22 Bradypus torquatus and 7 Bradypus variegatus. Serum samples were tested using neutralization test and hemagglutination inhibition test to detect total antibodies against 26 different arboviruses. The overall prevalence of arboviruses was 36.6% (51/139), with the genus Flavivirus having the highest prevalence (33.1%; 46/139), followed by Phlebovirus (5.0%; 7/139), Orthobunyavirus (4.3%; 6/139) and Alphavirus (0.7%; 1/139). Monotypic reactions suggest that the wild animals were exposed naturally to at least twelve arboviruses. Added results from the neutralization test, animals were exposed to thirteen arboviruses. Most of these viruses are maintained in transmission cycles independent of human hosts, although antibodies against dengue virus serotypes 1, 2 and 3 were found in this study. To our knowledge, this is the first study reporting exposure to arboviruses in L. chrysomelas, S. xanthosternos and B. torquatus. Our results also highlight that the Southern Bahia Atlantic Forest has a variety of vertebrate hosts and potential vectors, which may support the emergence or re-emergence of arboviruses, including those pathogenic to humans.

Zoos and public health: A partnership on the One Health frontier.

Today, accredited zoos are not just places for entertainment, they are actively involved in research for conservation and health. During recent decades in which the challenges for biodiversity conservation and public health have escalated, zoos have made significant changes to address these difficulties. Zoos increasingly have four key areas of focus: education, recreation, conservation, and research. These key areas are important in addressing an interrelated global conservation (i.e. habitat and wildlife loss) and public health crisis. Zoo and public health professionals working together within a One Health framework represent a powerful alliance to address current and future conservation and public health problems around the world. For researchers, practitioners, and students, the collaboration between zoos and public health institutions offers the opportunity to both teach and operationalize this transdisciplinary approach. Using examples from our programs, we give a template for moving forward with collaborative initiatives and sustainable solutions involving partners in both zoos and public health institutions. We provide examples of cooperative programs and suggest a model for consideration in the development of further activities in this area.

Serosurvey of Coxiella burnetii (Q fever) in Dromedary Camels (Camelus dromedarius) in Laikipia County, Kenya.

Dromedary camels (Camelus dromedarius) are an important protein source for people in semi-arid and arid regions of Africa. In Kenya, camel populations have grown dramatically in the past few decades resulting in the potential for increased disease transmission between humans and camels. An estimated four million Kenyans drink unpasteurized camel milk, which poses a disease risk. We evaluated the seroprevalence of a significant zoonotic pathogen, Coxiella burnetii (Q fever), among 334 camels from nine herds in Laikipia County, Kenya. Serum testing revealed 18.6% positive seroprevalence of Coxiella burnetii (n = 344). Increasing camel age was positively associated with C. burnetii seroprevalence (OR = 5.36). Our study confirmed that camels living in Laikipia County, Kenya, have been exposed to the zoonotic pathogen, C. burnetii. Further research to evaluate the role of camels in disease transmission to other livestock, wildlife and humans in Kenya should be conducted.

Multiple lineages of Avian malaria parasites (Plasmodium) in the Galapagos Islands and evidence for arrival via migratory birds.

Haemosporidian parasites in the genus Plasmodium were recently detected through molecular screening in the Galapagos Penguin (Spheniscus mendiculus). We summarized results of an archipelago-wide screen of 3726 endemic birds representing 22 species for Plasmodium spp. through a combination of molecular and microscopy techniques. Three additional Plasmodium lineages were present in Galapagos. Lineage A-infected penguins, Yellow Warblers (Setophaga petechia aureola), and one Medium Ground Finch (Geospiza fortis) and was detected at multiple sites in multiple years [corrected]. The other 3 lineages were each detected at one site and at one time; apparently, they were transient infections of parasites not established on the archipelago. No gametocytes were found in blood smears of infected individuals; thus, endemic Galapagos birds may be dead-end hosts for these Plasmodium lineages. Determining when and how parasites and pathogens arrive in Galapagos is key to developing conservation strategies to prevent and mitigate the effects of introduced diseases. To assess the potential for Plasmodium parasites to arrive via migratory birds, we analyzed blood samples from 438 North American breeding Bobolinks (Dolichonyx oryzivorus), the only songbird that regularly migrates through Galapagos. Two of the ephemeral Plasmodium lineages (B and C) found in Galapagos birds matched parasite sequences from Bobolinks. Although this is not confirmation that Bobolinks are responsible for introducing these lineages, evidence points to higher potential arrival rates of avian pathogens than previously thought. Linajes Múltiples de Parásitos de Malaria Aviar (Plasmodium) en las Islas Galápagos y Evidencia de su Arribo por Medio de Aves Migratorias.

Conservation medicine.

The Field Veterinary Program (FVP) of the Wildlife Conservation Society (WCS) was created in 1989 to combat the wildlife disease and health problems that increasingly complicate the process of wildlife conservation. The FVP provides veterinary services for the more than 300 WCS conservation projects located in more than 50 countries around the world. Most of these projects are in tropical regions and many have a wildlife/domestic livestock component. Wildlife health care provided by the FVP staff includes (1) identifying critical health factors; (2) monitoring health status; (3) crisis intervention; (4) developing and applying new technologies; (5) animal handling and welfare concerns; and (6) training. Additionally, the staff of the FVP give expert advice to many governmental and non-governmental agencies that are involved in setting policies directly related to wildlife health and conservation issues. In this paper, two FVP projects are presented as examples of studies that have increased our understanding of the role wildlife diseases may play in the health of livestock and human populations, as well as the role humans and livestock may play in the health of wildlife populations. Examples of the collaborative work between the FVP staff and scientists from many disciplines (e.g., acarologists, mycobacterium experts, ecologists, and biologists) are also presented.

Canine distemper in terrestrial carnivores: a review.

Canine distemper virus is a member of the genus Morbillivirus in the family Paramyxoviridae. Canine distemper has been recorded in domestic dogs for centuries. It is now recognized as a worldwide problem of carnivores and has the second highest fatality rate of any infectious disease, after rabies, in domestic dogs. The importance of this disease in nondomestic animals has become evident with vaccine-induced infections in a variety of species and large-scale epidemics in captive and free-ranging felids. To date, canine distemper has been reported in all families of terrestrial carnivores: Canidae, Felidae, Hyaenidae, Mustelidae, Procyonidae, Ursidae, and Viverridae. Veterinarians, including those working with nondomestic carnivores, should be familiar with the clinical signs, diagnosis, and clinical management of this disease.

Morbidity and mortality associated with a new mycoplasma species from captive American alligators (Alligator mississippiensis).

Nine of 74 American alligators (Alligator mississippiensis) from a captive Florida herd of 3-4-m-long, 200-350-kg, adult males greater than 30 yr of age died within a 10-day period during 1995. Nonspecific clinical signs included anorexia, lethargy, muscle weakness, paraparesis, bilateral white ocular discharge, and various degrees of periocular, facial, cervical, and limb edema. Pneumonia, pericarditis, and arthritis were found on postmortem evaluation of the spontaneously dead and euthanatized alligators. Rapidly growing mycoplasmas were identified by culture, and mycoplasma nucleotide sequences were identified by polymerase chain reaction testing of fresh lung and synovial fluid from an affected alligator. Culture of banked frozen lung from necropsy specimens and fresh lung and fresh synovial fluid from newly affected alligators confirmed the presence of a new mycoplasma species in seven of eight individuals. Oxytetracycline was administered, but related deaths continued for 6 mo until only 14 of the initial alligators remained. An enzyme-linked immunosorbent assay to detect antibody was developed, and the organism was transmitted experimentally to naive juvenile alligators, although the source of the organism, Mycoplasma sp. (ATCC 700619), has not been identified. The alligator isolate is a novel species in the mycoplasma family because its nucleotide sequence does not match those of over 75 characterized mycoplasma species. Such factors as population density, animal age, and mycoplasmal virulence likely contributed to the course of disease.

Cranial edema associated with a protein-losing nephropathy in a golden-mantled flying fox (Pteropus pumilus).

An adult golden-mantled flying fox (Pteropus pumilus) was diagnosed with nephrotic syndrome on the basis of the findings of proteinuria, hypoalbuminemia, hypercholesterolemia, and cranial edema. Membranoproliferative glomerulitis and interstitial nephritis were confirmed antemortem by renal biopsy. The bat had received seven injections of oxytocin in the period immediately prior to presentation. The possible role of oxytocin in the development of the nephropathy is discussed. Supportive care and treatment with a single plasma transfusion, furosemide, and prednisone led to a gradual but complete resolution of the nephrotic syndrome in this animal.

Anesthetic and cardiorespiratory effects of tiletamine-zolazepam-medetomidine in cheetahs.

OBJECTIVE: To evaluate anesthetic and cardiorespiratory effects of an intramuscular injection of a tiletamine-zolazepam-medetomidine combination in cheetahs. DESIGN: Prospective study. ANIMALS: 17 adult captive cheetahs. PROCEDURE: The anesthetic combination was administered intramuscularly via a dart. Induction quality, duration of lateral recumbency, duration of recovery, and quality of anesthetic reversal with atipamezole were assessed. Cardiorespiratory variables (arterial blood gas partial pressures, arterial blood pressure, heart and respiratory rates, end-tidal CO2, oxygen saturation, and rectal temperature) were measured during anesthesia. RESULTS: Sedation and lateral recumbency developed within 1.9 +/- 1.0 (mean +/- SD) and 4.3 +/- 2.0 minutes of drug administration, respectively. Clinically acceptable cardiorespiratory and blood gas values were recorded for at least 87 minutes after drug administration in all but 1 cheetah. Hypoxemia and arrhythmias developed in 1 cheetah breathing room air but resolved after treatment with oxygen. Hypertension developed in all cheetahs. Significant differences in heart and respiratory rates, mean arterial blood pressure, arterial pH, partial pressure of oxygen, and hemoglobin saturation were found between cheetahs that did and did not receive oxygen supplementation. After administration of atipamezole, sternal recumbency and mobility returned within 6.9 +/- 5.8 and 47.5 +/- 102.2 minutes, respectively. Postreversal sedation, which lasted approximately 4 hours, developed in 4 cheetahs. CLINICAL IMPLICATIONS: Tiletamine-zolazepam-medetomidine delivered via a dart provided an alternative method for induction and maintenance of anesthesia in cheetahs. Atipamezole at the dose used was effective for reversal of this combination in the initial phase of anesthesia.

A retrospective study of morbidity and mortality of raptors in Florida: 1988-1994.

A retrospective study was conducted on 390 raptors admitted to the University of Florida Veterinary Medical Teaching Hospital (VMTH) during 1988-1994. Representatives of 20 species were admitted; the five most common species were the barred owl (Strix varia, 72), eastern sreech owl (Otus asio, 63), red-shouldered hawk (Buteo lineatus, 49), bald eagle (Haleaeetus leucocephalus, 43), and red-tailed hawk (Buteo jamaicensis, 38). A primary clinical diagnosis was determined in 340 (87%) of the 390 raptors admitted to the VMTH; a diagnosis was not made for the remaining 50 birds. Eighty-two percent (279) had traumatic injuries, and 87% (243) of those were directly related to human activity. The primary clinical diagnoses in the remaining 61 raptors included toxicosis (21), poor nutrition (15), infectious disease (11), orphaned young (11), and electrocution (3). The disposition of the 390 raptors was as follows: 61% (237) died or euthanized, 21% (80) released to the wild, 15% (57) outcome unknown, and 4% (16) permanent captives. Necropsies were performed on 32 of the 237 raptors that died.

Heartworm (Dirofilaria immitis) disease and glomerulonephritis in a black-footed cat (Felis nigripes).

A 6-yr-old, 1.36-kg, intact female black-footed cat (Felis nigripes) was presented to the Veterinary Medical Teaching Hospital, University of Florida, with a history of depression, lethargy, and anorexia. Cardiac dysfunction and renal failure were diagnosed on the basis of antemortem and postmortem findings. At necropsy, heartworms (Dirofilaria immitis), glomerulonephritis, and endometritis were present. The glomerulonephritis could have been immune mediated and may have been associated with the heartworm infection or the chronic endometritis or both. Heartworm disease should be included in the list of differential diagnoses for any exotic cat housed outdoors in an endemic heartworm region that dies peracutely or has suggestive gastrointestinal or respiratory signs. Heartworm prophylaxis and annual serologic testing in exotic cats housed outdoors in heartworm endemic regions are recommended.

A review of heartwater and the threat of introduction of Cowdria ruminantium and Amblyomma spp. ticks to the American mainland.

Heartwater, caused by the rickettsial agent Cowdria ruminantium, is one of the most devastating livestock diseases in sub-Saharan Africa. In addition to domestic cattle, sheep, and goats, a variety of nondomestic species can acquire subclinical and clinical infections. Recent epidemiologic findings that demonstrate a long-term host carrier state in domestic and wild ruminants, intrastadial transmission by the tick vectors (Amblyomma spp.), vertical transmission of the agent from cows to their calves, and the presence of both C. ruminantium and Amblyomma variegatum in the Caribbean suggest that the introduction of this exotic disease to the American mainland is a significant threat. Veterinarians working with wildlife should be familiar with this disease and should follow appropriate preventive measures to minimize the risk of infection in captive and wild populations of ruminants.

The epidemiology of heartwater: Establishment and maintenance of endemic stability.

Although heartwater (Cowdria ruminantium infection) is one of the most economically important tick-borne diseases of sub-Saharan Africa, its epidemiology he's remained poorly understood until recently. New data, suggesting that heartwater is present in an endemically stable state in much of sub-Saharan Africa and demonstrating vertical transmission of Cowdria ruminantium in the field, have altered previously accepted views on heartwater epidemiology. In this paper, Sharon Deem and colleagues present an overview of the epidemiology of heartwater based on recent studies, discuss the factors that make endemic stability possible, make recommendations for future directions in research, and provide a foundation for the development of epidemiological models.

Demonstration of vertical transmission of Cowdria ruminantium, the causative agent of heartwater, from cows to their calves.

One of the most important questions about the epidemiology of heartwater in the field is how Cowdria ruminatium is transmitted within vertebrate host populations. In this study vertical transmission of C. ruminantium from cows to their calves was demonstrated. Twelve mixed-breed calves, born to dams living in a heartwater-endemic area of Zimbabwe, were tested post-natally for the presence of C. ruminantium. Vertical transmission was demonstrated to occur under natural field conditions using tests in which uninfected laboratory-reared Amblyomma ticks were fed on neonatal calves and subsequently either fed on, or inoculated into, susceptible small ruminants or tested by a polymerase chain reaction (PCR) assay. Prior to natural Amblyomma tick infestation, C. ruminantium infection in 5 of the 12 calves was confirmed by tick transmission to small ruminants and 11 of the 12 calves tested positive based on PCR analysis of ticks fed on them. The role of colostral cells, as one mode of infection, was demonstrated by the transmission of C. ruminantium to three out of five goats inoculated intravenously with viable colostral cells collected from dams living in a heartwater-endemic area. The significance of vertical transmission is presented in relation to the epidemiology and control of heartwater.

Colostrum from dams living in a heartwater-endemic area influences calfhood immunity to Cowdria ruminantium.

Two studies were carried out to determine whether colostrum from dams living in a heartwater-endemic area has an influence on calfhood immunity to Cowdria ruminantium infection. The initial study was conducted using Friesian calves originating from a heartwater-free herd. Experimental groups consisted of calves receiving colostrum from dams living in a heartwater-endemic area and known to be exposed to C. ruminantium (as determined by the indirect fluorescent antibody test) and calves receiving colostrum from dams located in a heartwater-free area. All calves were challenged at 3 days of age with a homologous C. ruminantium blood stabilate originating from the same area as the endemic colostrum. A significant difference in both the intensity of clinical reactions and percentage of fatal heartwater cases was noted between the two groups of calves. Three of the five calves receiving the colostrum free of C. ruminantium-specific antibodies succumbed to challenge, whereas none of the five calves receiving the colostrum from the heartwater-endemic area showed any clinical reactions. A second similar study was carried out using 12 mixed breed calves born in a heartwater-endemic area of Zimbabwe. The results from this study supported the findings of the first. The significant role of colostrum in calfhood immunity to C. ruminantium infection is discussed in relation to the epidemiology and control of heartwater.

The relationship between tick (Amblyomma hebraeum) infestation and immunity to heartwater (Cowdria ruminantium infection) in calves in Zimbabwe.

The occurrence of endemic stability for heartwater (Cowdria ruminantium infection) is a controversial issue, because the means by which young cattle and other neonatal ruminants become infected and acquire immunity to the disease have never been adequately explained. We conducted a study in a heartwater-endemic area in southeastern Zimbabwe to investigate the relationships between calf immunity to C. ruminatium, infestations of the tick vector Amblyomma hebraeum and dam, colostral and calf antibody titres to C. ruminantium. Two groups of cows (tick-infested and acaricide-treated) were artificially inseminated and then monitored through pregnancy and lactation by means of tick counts and serum antibody titres. The calves born to the cows in each treatment group were similarly monitored from birth until after weaning, when they were challenged with a heartwater stabilate (Ball-3 vaccine). Colostrum was collected from the cows on the days that the calves were born. Serum and colostrum samples were screened for Cowdria-specific antibodies using an indirect fluorescent antibody test. The cows and calves in the acaricide-treated group remained essentially tick-free for the duration of the study. The cows in the tick-infested group were continuously infested with A. hebraeum, but their calves only became infested between 12 and 31 weeks after birth. Cowdria-specific antibodies were detected in the sera of the cows and calves and in the colostrum of both treatment groups, but the titres were consistently higher in the tick-infested group than in the acaricide-treated group. Antibodies, probably of maternal origin since the precolostral serum titres were negative, were present in the calves of both groups for at least 8 weeks after birth. Between Weeks 24 and 52 postpartum, the antibody titres of the tick-infested group of calves were significantly correlated with the numbers of A. hebraeum present on the animals. The antibody titres of the calves in the acaricide-treated group increased considerably following challenge with heartwater stabilate, 60 weeks after birth. No clinical heartwater was detected in either group of calves following inoculation of stabilate, and it was concluded that the calves in both groups were immune to the disease. In the acaricide-treated group, immunity did not correlate with exposure to tick-transmitted infections. Hence, we concluded that the calves in both groups had probably been infected by vertical transmission around the time of birth. Such early infections are likely to have been controlled by maternal antibodies or by an unidentified immune mechanism.(ABSTRACT TRUNCATED AT 400 WORDS)

Development and evaluation of PCR assay for detection of low levels of Cowdria ruminantium infection in Amblyomma ticks not detected by DNA probe.

The sensitivities of a PCR assay and a DNA probe assay were compared for the detection of Cowdria ruminantium in Amblyomma ticks that were fed on C. ruminantium-infected, clinically reacting, and recovered carrier animals. The PCR assay and DNA probe detected infection in 86.0 and 37.0%, respectively, of 100 ticks fed on a febrile animal. In 75 ticks fed on carrier animals, PCR and the DNA probe detected infection in 28.0 and 1.33% of ticks, respectively. This demonstrates that the DNA probe has poor sensitivity for the detection of low levels of infection in ticks and that PCR is necessary for this purpose. The PCR assay had a detection limit of between 1 and 10 C. ruminantium organisms and did not amplify DNA from Ehrlichia canis, which is phylogenetically closely related to C. ruminantium, Theileria parva, or uninfected Amblyomma hebraeum or A. variegatum. PCR detected infection in A. hebraeum and A. variegatum adult ticks infected with one of six geographically different C. ruminantium strains. Amplification was also possible from desiccated ticks and ticks fixed in 70% ethanol, 10% buffered formalin, or 2% glutaraldehyde. The PCR assay supersedes the DNA probe and older detection methods for the detection of C. ruminantium in ticks, particularly those fed on carrier animals, and is suitable for both prospective and retrospective studies which require accurate detection of C. ruminantium in individual ticks. Application of the PCR assay should significantly improve the understanding of heartwater epidemiology, particularly through the determination of field tick infection rates.