ABSTRACT
INTRODUCTION: Three randomised controlled trials (RCTs) have demonstrated that first-line cryoballoon pulmonary vein isolation decreases atrial tachycardia in patients with symptomatic paroxysmal atrial fibrillation (PAF) compared with antiarrhythmic drugs (AADs). The aim of this study was to develop a cost-effectiveness model (CEM) for first-line cryoablation compared with first-line AADs for the treatment of PAF. The model used a Danish healthcare perspective. METHODS: Individual patient-level data from the Cryo-FIRST, STOP AF and EARLY-AF RCTs were used to parameterise the CEM. The model structure consisted of a hybrid decision tree (one-year time horizon) and a Markov model (40-year time horizon, with a three-month cycle length). Health-related quality of life was expressed in quality-adjusted life years (QALYs). Costs and benefits were discounted at 3% per year. Model outcomes were produced using probabilistic sensitivity analysis. RESULTS: First-line cryoablation is dominant, meaning it results in lower costs (-2,663) and more QALYs (0.18) when compared to first-line AADs. First-line cryoablation also has a 99.96% probability of being cost-effective, at a cost-effectiveness threshold of 23,200 per QALY gained. Regardless of initial treatment, patients were expected to receive â¼ 1.2 ablation procedures over a lifetime horizon. CONCLUSION: First-line cryoablation is both more effective and less costly (i.e. dominant), when compared with AADs for patients with symptomatic PAF in a Danish healthcare system.
Subject(s)
Anti-Arrhythmia Agents , Atrial Fibrillation , Cost-Benefit Analysis , Cryosurgery , Drug Costs , Markov Chains , Models, Economic , Quality of Life , Quality-Adjusted Life Years , Randomized Controlled Trials as Topic , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Atrial Fibrillation/economics , Atrial Fibrillation/therapy , Atrial Fibrillation/drug therapy , Atrial Fibrillation/physiopathology , Humans , Cryosurgery/economics , Cryosurgery/adverse effects , Denmark , Anti-Arrhythmia Agents/therapeutic use , Anti-Arrhythmia Agents/economics , Treatment Outcome , Time Factors , Male , Female , Middle Aged , Decision Support Techniques , Aged , Pulmonary Veins/surgery , Pulmonary Veins/physiopathology , Cost Savings , Decision TreesABSTRACT
INTRODUCTION: Three recent randomised controlled trials have demonstrated that pulmonary vein isolation as an initial rhythm control strategy with cryoablation reduces atrial arrhythmia recurrence in patients with symptomatic paroxysmal atrial fibrillation (PAF) compared with antiarrhythmic drug (AAD) therapy. The aim of this study was to evaluate the cost-effectiveness of first-line cryoablation compared with first-line AADs for treating symptomatic PAF in an English National Health Service (NHS) setting. METHODS: Individual patient-level data from 703 participants with PAF enrolled into Cryo-FIRST (Catheter Cryoablation Versus Antiarrhythmic Drug as First-Line Therapy of Paroxysmal Atrial Fibrillation), STOP AF First (Cryoballoon Catheter Ablation in an Antiarrhythmic Drug Naive Paroxysmal Atrial Fibrillation) and EARLY-AF (Early Aggressive Invasive Intervention for Atrial Fibrillation) were used to derive the parameters applied in the cost-effectiveness model (CEM). The CEM comprised a hybrid decision tree and Markov structure. The decision tree had a 1-year time horizon and was used to inform the initial health state allocation in the first cycle of the Markov model (40-year time horizon; 3-month cycle length). Health benefits were expressed in quality-adjusted life years (QALYs). Costs and benefits were discounted at 3.5% per year. Model outcomes were generated using probabilistic sensitivity analysis. RESULTS: The results estimated that cryoablation would yield more QALYs (+0.17) and higher costs (+£641) per patient over a lifetime than AADs. This produced an incremental cost-effectiveness ratio of £3783 per QALY gained. Independent of initial treatment, individuals were expected to receive ~1.2 ablations over a lifetime. There was a 45% relative reduction in time spent in AF health states for those initially treated with cryoablation. DISCUSSION: AF rhythm control with first-line cryoablation is cost effective compared with first-line AADs in an English NHS setting.
Subject(s)
Atrial Fibrillation , Cryosurgery , Humans , Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Atrial Fibrillation/surgery , Cost-Benefit Analysis , State Medicine , Anti-Arrhythmia Agents/adverse effects , Cryosurgery/adverse effects , Cryosurgery/methodsABSTRACT
BACKGROUND: The EARLY-AF (NCT02825979), STOP AF First (NCT03118518), and Cryo-FIRST (NCT01803438) randomised controlled trials (RCTs) demonstrated that cryoballoon pulmonary vein isolation reduces atrial fibrillation (AF) recurrence compared with antiarrhythmic drugs (AADs) in patients with symptomatic paroxysmal atrial fibrillation (PAF). The present study developed a cost-effectiveness model (CEM) of first-line cryoablation compared with first-line AADs for PAF, from the Canadian health care payer's perspective. METHODS: Data from the 3 RCTs were analysed to estimate key CEM parameters. The model structure used a decision tree for the first 12 months and a Markov model with a 3-month cycle length for the remaining lifetime time horizon. Costs were set at 2023 Canadian dollars, health benefits were expressed as quality-adjusted life years (QALYs), and both were discounted 3% annually. Probabilistic sensitivity analysis (PSA) considered parameter uncertainty. RESULTS: The statistical analysis estimated that first-line cryoablation generates a 47% reduction (P < 0.001) in the rate of AF recurrence, a 73% reduction in the rate of subsequent ablation (P < 0.001), and a 4.3% (P = 0.025) increase in health-related quality of life, compared with first-line AADs. The PSA indicates that an individual treated with first-line cryoablation accrues less costs (-$3,862) and more QALYs (0.19) compared with first-line AADs. Cryoablation is cost-saving in 98.4% of PSA iterations and has a 99.9% probability of being cost-effective at a cost-effectiveness threshold of $50,000 per QALY gained. Cost-effectiveness results were robust to changes in key model parameters. CONCLUSIONS: First-line cryoballoon ablation is cost-effective when compared with AADs for patients with symptomatic PAF.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Cryosurgery , Humans , Atrial Fibrillation/drug therapy , Atrial Fibrillation/surgery , Cost-Benefit Analysis , Anti-Arrhythmia Agents/therapeutic use , Catheter Ablation/methods , Canada/epidemiology , Treatment Outcome , RecurrenceABSTRACT
The impacts of large terrestrial volcanic eruptions are apparent from satellite monitoring and direct observations. However, more than three quarters of all volcanic outputs worldwide lie submerged beneath the ocean, and the risks they pose to people, infrastructure, and benthic ecosystems remain poorly understood due to inaccessibility and a lack of detailed observations before and after eruptions. Here, comparing data acquired between 2015 - 2017 and 3 months after the January 2022 eruption of Hunga Volcano, we document the far-reaching and diverse impacts of one of the most explosive volcanic eruptions ever recorded. Almost 10 km3 of seafloor material was removed during the eruption, most of which we conclude was redeposited within 20 km of the caldera by long run-out seafloor density currents. These powerful currents damaged seafloor cables over a length of >100 km, reshaped the seafloor, and caused mass-mortality of seafloor life. Biological (mega-epifaunal invertebrate) seafloor communities only survived the eruption where local topography provided a physical barrier to density currents (e.g., on nearby seamounts). While the longer-term consequences of such a large eruption for human, ecological and climatic systems are emerging, we expect that these previously-undocumented refugia will play a key role in longer-term ecosystem recovery.
ABSTRACT
Volcanic eruptions on land create hot and fast pyroclastic density currents, triggering tsunamis or surges that travel over water where they reach the ocean. However, no field study has documented what happens when large volumes of erupted volcanic material are instead delivered directly into the ocean. We show how the rapid emplacement of large volumes of erupted material onto steep submerged slopes triggered extremely fast (122 kilometers per hour) and long-runout (>100 kilometers) seafloor currents. These density currents were faster than those triggered by earthquakes, floods, or storms, and they broke seafloor cables, cutting off a nation from the rest of the world. The deep scours excavated by these currents are similar to those around many submerged volcanoes, providing evidence of large eruptions at other sites worldwide.
ABSTRACT
Background: Three recent randomized controlled trials have demonstrated that, as an initial rhythm control strategy, first-line cryoballoon ablation (cryoablation) reduces atrial arrhythmia recurrence compared with antiarrhythmic drugs (AADs) in patients with symptomatic paroxysmal atrial fibrillation (PAF). Objective: The study sought to evaluate the cost-effectiveness of first-line cryoablation compared with first-line AADs for treating symptomatic PAF from a U.S. Medicare payer perspective. Methods: Individual patient-level data from 703 participants with PAF enrolled into the Cryo-FIRST (NCT01803438), STOP AF First (NCT03118518), and EARLY-AF (NCT02825979) trials were used to derive parameters for the cost-effectiveness model. The cost-effectiveness model used a hybrid decision tree and Markov structure. The decision tree had a 1-year time horizon and was used to inform the initial health state allocation in the first cycle of the Markov model. The Markov model used a 40-year time horizon (3-month cycle length). Health benefits were expressed in quality-adjusted life years (QALYs). Costs and benefits were discounted at 3% per year. Results: Cryoablation was estimated to yield higher QALYs (+0.17) and higher costs (+$4274) per patient over a 40-year time horizon than AADs. Ultimately, this produced an average incremental cost-effectiveness ratio of $24,637 per QALY gained. Independent of initial treatment, individuals were expected to receive â¼1.2 ablations over a lifetime. There was a 45% relative reduction in time spent in atrial fibrillation health states for those initially treated with cryoablation compared with AADs. Conclusion: Initial rhythm control with first-line cryoballoon ablation is highly cost-effective compared with first-line AADs from a U.S. Medicare payer perspective.
ABSTRACT
Background Accurate breast cancer risk assessment after a negative screening result could enable better strategies for early detection. Purpose To evaluate a deep learning algorithm for risk assessment based on digital mammograms. Materials and Methods A retrospective observational matched case-control study was designed using the OPTIMAM Mammography Image Database from the National Health Service Breast Screening Programme in the United Kingdom from February 2010 to September 2019. Patients with breast cancer (cases) were diagnosed following a mammographic screening or between two triannual screening rounds. Controls were matched based on mammography device, screening site, and age. The artificial intelligence (AI) model only used mammograms at screening before diagnosis. The primary objective was to assess model performance, with a secondary objective to assess heterogeneity and calibration slope. The area under the receiver operating characteristic curve (AUC) was estimated for 3-year risk. Heterogeneity according to cancer subtype was assessed using a likelihood ratio interaction test. Statistical significance was set at P < .05. Results Analysis included patients with screen-detected (median age, 60 years [IQR, 55-65 years]; 2044 female, including 1528 with invasive cancer and 503 with ductal carcinoma in situ [DCIS]) or interval (median age, 59 years [IQR, 53-65 years]; 696 female, including 636 with invasive cancer and 54 with DCIS) breast cancer and 1:1 matched controls, each with a complete set of mammograms at the screening preceding diagnosis. The AI model had an overall AUC of 0.68 (95% CI: 0.66, 0.70), with no evidence of a significant difference between interval and screen-detected (AUC, 0.69 vs 0.67; P = .085) cancer. The calibration slope was 1.13 (95% CI: 1.01, 1.26). There was similar performance for the detection of invasive cancer versus DCIS (AUC, 0.68 vs 0.66; P = .057). The model had higher performance for advanced cancer risk (AUC, 0.72 ≥stage II vs 0.66 Subject(s)
Breast Neoplasms
, Carcinoma, Intraductal, Noninfiltrating
, Humans
, Female
, Middle Aged
, Breast Neoplasms/diagnostic imaging
, Artificial Intelligence
, Case-Control Studies
, Retrospective Studies
, State Medicine
ABSTRACT
The combination of perinatal acidemia with postnatal hyperoxia is associated with a higher incidence of hypoxic-ischemic encephalopathy (HIE) in newborn infants. In neonatal cardiac arrest, current International Liaison Committee on Resuscitation (ILCOR) and Neonatal Resuscitation Program (NRP) guidelines recommend increasing inspired O2 to 100% during chest compressions (CC). Following the return of spontaneous circulation (ROSC), gradual weaning from 100% O2 based on pulse oximetry (SpO2) can be associated with hyperoxia and risk for cerebral tissue injury owing to oxidative stress. We hypothesize that compared to gradual weaning from 100% O2 with titration based on preductal SpO2, abrupt or rapid weaning of inspired O2 to 21% after ROSC or use of 21% O2 during CC followed by upward titration of inspired O2 to achieve target SpO2 after ROSC will limit hyperoxia after ROSC. Nineteen lambs were randomized before delivery and asphyxial arrest was induced by umbilical cord occlusion. There was no difference in oxygenation during chest compressions between the three groups. Gradual weaning of inspired O2 from 100% O2 after ROSC resulted in supraphysiological PaO2 and higher cerebral oxygen delivery compared to 21% O2 during CC or 100% O2 during CC followed by abrupt weaning to 21% O2 after ROSC. The use of 21% O2 during CC was associated with very low PaO2 after ROSC and higher brain tissue lactic acid compared to other groups. Our findings support the current recommendations to use 100% O2 during CC and additionally suggest the benefit of abrupt decrease in inspired oxygen to 21% O2 after ROSC. Clinical studies are warranted to investigate optimal oxygen titration after chest compressions and ROSC during neonatal resuscitation.
ABSTRACT
On January 15th, 2022, at approximately 4:47 pm local time (0347 UTC), several weeks of heightened activity at the Hunga volcano 65 km northwest of Tongatapu, culminated in an 11-h long violent eruption which generated a significant near-field tsunami. Although the Kingdom of Tonga lies astride a large and tsunamigenic subduction zone, it has relatively few records of significant tsunami. Assessment activities took place both remotely and locally. Between March and June 2022, a field team quantified tsunami runup and inundation on the main populated islands Tongatapu and Eua, along with several smaller islands to the north, including the Ha'apai Group. Peak tsunami heights were ~ 19 m in western Tongatapu, ~ 20 m on south-eastern Nomuka Iki island and ~ 20 m on southern Tofua, located ~ 65 km S and E and 90 km N from Hunga volcano, respectively. In western Tongatapu, the largest tsunami surge overtopped a 13-15 m-high ridge along the narrow Hihifo peninsula in several locations. Analysis of tide gauge records from Nukualofa (which lag western Tongatapu arrivals by ~ 18-20 min), suggest that initial tsunami surges were generated prior to the largest volcanic explosions at ~ 0415 UTC. Further waves were generated by ~ 0426 UTC explosions that were accompanied by air-pressure waves. Efforts to model this event are unable to reproduce the timing of the large tsunami wave that toppled a weather station and communication tower on a 13 m-high ridge on western Tongatapu after 0500 UTC. Smaller tsunami waves continued until ~ 0900, coincident with a second energetic phase of eruption, and noted by eyewitnesses on Tungua and Mango Islands. Despite an extreme level of destruction caused by this tsunami, the death toll was extraordinarily low (4 victims). Interviews with witnesses and analysis of videos posted on social media suggest that this can be attributed to the arrival of smaller 'pre tsunami' waves that prompted evacuations, heightened tsunami awareness due to tsunami activity and advisories on the day before, the absence of tourists and ongoing tsunami education efforts since the 2009 Niuatoputapu, Tonga tsunami. This event highlights an unexpectedly great hazard from volcanic tsunami worldwide, which in Tonga's case overprints an already extreme level of tectonic tsunami hazard. Education and outreach efforts should continue to emphasize the 'natural warning signs' of strong ground shaking and unusual wave and current action, and the importance of self-evacuation from coastal areas of low-lying islands. The stories of survival from this event can be used as global best practice for personal survival strategies from future tsunami. Supplementary Information: The online version contains supplementary material available at 10.1007/s00024-022-03215-5.
ABSTRACT
Volume expanders are indicated in the delivery room when an asphyxiated neonate is not responding to the steps of neonatal resuscitation and has signs of shock or a history of acute blood loss. Fetal blood loss (e.g., feto-maternal hemorrhage) may contribute to perinatal asphyxia. Cord compression or a tight nuchal cord can selectively occlude a thin-walled umbilical vein, resulting in feto-placental transfusion and neonatal hypovolemia. For severe bradycardia or cardiac arrest secondary to fetal blood loss, Neonatal Resuscitation Program (NRP) recommends intravenous volume expanders (crystalloids such as normal saline or packed red blood cells) infused over 5 to 10 min. Failure to recognize hypovolemia and subsequent delay in volume replacement may result in unsuccessful resuscitation due to lack of adequate cardiac preload. However, excess volume load in the presence of myocardial dysfunction from hypoxic-ischemic injury may precipitate pulmonary edema and intraventricular hemorrhage (especially in preterm infants). Emergent circumstances and ethical concerns preclude the performance of prospective clinical studies evaluating volume replacement during neonatal resuscitation. Translational studies, observational data from registries and clinical trials are needed to investigate and understand the role of volume replacement in the delivery room in term and preterm neonates. This article is a narrative review of the causes and consequences of acute fetal blood loss and available evidence on volume replacement during neonatal resuscitation of asphyxiated neonates.
ABSTRACT
PROBLEM: In March 2020, the novel coronavirus 2019 (COVID-19) pandemic spread rapidly within the United States and began overwhelming the health care system. To conserve personal protective equipment, reduce the spread of the virus, and keep student learners safe, leaders of medical schools across the country made the difficult decision to suspend in-person clinical experiences. As medical students were sent home and hospital systems ramped up their response to the virus, many essential health care workers (HCWs) faced an immediate challenge. As "nonessential" services such as schools and daycare centers abruptly closed, HCWs serving on the frontlines in inpatient settings needed a way to both fight the pandemic and care for their children. APPROACH: Medical students at Oregon Health & Science University were able to rapidly OR organize to provide childcare for essential HCWs. For roughly 8 weeks following the state of emergency (March 13 through May 15, 2020), students used Twitter and emerging technology to match families in need of childcare with a trainee volunteer. OUTCOMES: By May 15th, the service had successfully fulfilled 181 of the 202 requests for childcare (90%) over the course of 8 weeks. Of the 181 completed childcare requests, 172 (95%) were fulfilled by an individual (1:1 volunteer-to-household pairing), and 9 (5%) were fulfilled by 2 or more volunteers. NEXT STEPS: The trainees who provided childcare will apply the skills learned (e.g., clear communication, grassroots organizing, triaging, leveraging new technology) to patient care. Broader applications for this system include organizing volunteers to conduct contract tracing or to provide public health information in languages other than English. Future research includes examining the effect of the service on the productivity, morale, and mental health of both those who provided and received childcare.
Subject(s)
COVID-19 , Child Care/organization & administration , Health Personnel , Students, Medical , Volunteers , Child , Child Care/methods , Child, Preschool , Emergencies , Humans , Infant , Oregon , Social MediaABSTRACT
Tuberculosis caused by Mycobacterium bovis is endemic in the African buffalo (Syncerus caffer) population in the Kruger National Park and other conservation areas in South Africa. The disease has been diagnosed in a total of 21 free ranging or semi-free ranging wildlife species in the country with highly variable presentations in terms of clinical signs as well as severity and distribution of tuberculous lesions. Most species are spillover or dead-end hosts without significant role in the epidemiology of the disease. White rhinoceroses (Ceratotherium simum) are translocated from the Kruger National Park in substantial numbers every year and a clear understanding of their risk to manifest overt tuberculosis disease and to serve as source of infection to other species is required. We report the findings of experimental infection of three white rhinoceroses with a moderately low dose of a virulent field isolate of Mycobacterium bovis. None of the animals developed clinical signs or disseminated disease. The susceptibility of the white rhinoceros to bovine tuberculosis was confirmed by successful experimental infection based on the ante mortem isolation of M. bovis from the respiratory tract of one rhinoceros, the presence of acid-fast organisms and necrotizing granulomatous lesions in the tracheobronchial lymph nodes and the detection of M. bovis genetic material by PCR in the lungs of two animals.
Subject(s)
Animals, Wild/microbiology , Mycobacterium bovis/pathogenicity , Perissodactyla/microbiology , Tuberculosis, Bovine/microbiology , Animals , Buffaloes/microbiology , Cattle , Mycobacterium bovis/isolation & purification , Tuberculosis, Bovine/transmissionABSTRACT
During high-speed pursuit of prey, the cheetah (Acinonyx jubatus) has been observed to swing its tail while manoeuvring (e.g. turning or braking) but the effect of these complex motions is not well understood. This study demonstrates the potential of the cheetah's long, furry tail to impart torques and forces on the body as a result of aerodynamic effects, in addition to the well-known inertial effects. The first-order aerodynamic forces on the tail are quantified through wind tunnel testing and it is observed that the fur nearly doubles the effective frontal area of the tail without much mass penalty. Simple dynamic models provide insight into manoeuvrability via simulation of pitch, roll and yaw tail motion primitives. The inertial and quasi-steady state aerodynamic effects of tail actuation are quantified and compared by calculating the angular impulse imparted onto the cheetah's body and its shown aerodynamic effects contribute to the tail's angular impulse, especially at the highest forward velocities.
ABSTRACT
An outbreak of feline panleukopaenia virus (FPLV) infection was diagnosed by pathology, electron microscopy and polymerase chain reaction (PCR) in vaccinated captive-bred subadult cheetahs in South Africa. Subsequent to this disease outbreak, 12 cases of FPLV diagnosed on histology were confirmed by PCR in captive African black-footed cat, caracal, cheetah, lion, ocelot and serval. Phylogenetic analyses of the viral capsid protein gene on PCR-positive samples, vaccine and National Center for Biotechnology Information (NCBI) reference strains identified a previously unknown strain of FPLV, present since at least 2006, that differs from both the inactivated and the modified live vaccine strains. A previously described South African strain from domestic cats and cheetahs was identified in a serval. Surveys of FPLV strains in South African felids are needed to determine the geographical and host species distribution of this virus. Since non-domestic species may be reservoirs of parvoviruses, and since these viruses readily change host specificity, the risks of FPLV transmission between captive-bred and free-ranging carnivores and domestic cats and dogs warrant further research.
Subject(s)
Disease Outbreaks/veterinary , Felidae , Feline Panleukopenia Virus/isolation & purification , Feline Panleukopenia/epidemiology , Acinonyx , Animals , Capsid Proteins/genetics , Cats , Feline Panleukopenia/diagnosis , Feline Panleukopenia/pathology , Feline Panleukopenia/virology , Feline Panleukopenia Virus/genetics , Female , Male , Phylogeny , Polymerase Chain Reaction/veterinary , Sequence Analysis, DNA/veterinary , South Africa/epidemiology , VaccinationABSTRACT
Toxoplasma gondii is a ubiquitous protozoan parasite that infects humans and many different animals, including felids. Many molecular and serologic tests have been developed for detection of T. gondii in a wide range of hosts. Loop-mediated isothermal amplification (LAMP) is a field-friendly technique that lacks the practical drawbacks of other molecular and serologic tests, and LAMP assays have been successfully developed for detection of T. gondii in fresh tissue samples. In the current study, both a previously published and a de-novo designed LAMP assay were compared to a quantitative real-time (q)PCR assay, for the detection of T. gondii in archived formalin-fixed, paraffin-embedded (FFPE) tissue samples from captive wildlife. The LAMP assays produced conflicting results, generating both false positives and false negatives. Furthermore, the LAMP assays were unable to positively identify samples with low levels of parasites as determined by qPCR and histopathology. Therefore, these LAMP assays may not be the most suitable assays for detection of T. gondii in archived FFPE and frozen tissue samples.
Subject(s)
Cat Diseases/diagnosis , Toxoplasma/isolation & purification , Toxoplasmosis/diagnosis , Animals , Animals, Wild , Cat Diseases/parasitology , Cats , DNA, Protozoan/analysis , False Positive Reactions , Nucleic Acid Amplification Techniques/veterinary , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Toxoplasma/genetics , Toxoplasmosis/parasitologyABSTRACT
Warthogs (Phacochoerus africanus) have been implicated as potential maintenance hosts of Mycobacterium bovis. Our preliminary investigation of bovine tuberculosis in three warthogs describes pathologic findings and associated positive serologic results in two infected animals. This demonstrates the potential use of serodiagnostic tests for M. bovis infection in this species.
Subject(s)
Mycobacterium bovis/isolation & purification , Swine Diseases/diagnosis , Tuberculosis/veterinary , Animals , Antibodies, Bacterial/blood , Female , Lymph Nodes/pathology , Male , Mycobacterium bovis/immunology , Serologic Tests/veterinary , Swine , Swine Diseases/microbiology , Tuberculosis/diagnosis , Tuberculosis/microbiologyABSTRACT
Over the past decade, several clustered, multispecies, wildlife mortality events occurred in the vicinity of two man-made earthen dams in the southern and south central regions of the Kruger National Park, South Africa. On field investigation, heavy cyanobacterial blooms were visible in these impoundments and analysis of water samples showed the dominance of Microcystis spp. (probably Microcystis aeruginosa). Macroscopic lesions seen at necropsy and histopathological lesions were compatible with a diagnosis of cyanobacterial intoxication. Laboratory toxicity tests and assays also confirmed the presence of significant levels of microcystins in water from the two dams. These outbreaks occurred during the dry autumn and early winter seasons when water levels in these dams were dropping, and a common feature was that all the affected dams were supporting a large number of hippopotamuses (Hippopotamus amphibius). It is hypothesised that hippopotamus' urine and faeces, together with agitation of the sediments, significantly contributed to internal loading of phosphates and nitrogen - leading to eutrophication of the water in these impoundments and subsequent cyanobacterial blooms. A major cause for concern was that a number of white rhinoceros (Ceratotherium simum) were amongst the victims of these bio-intoxication events. This publication discusses the eco-epidemiology and pathology of these clustered mortalities, as well as the management options considered and eventually used to address the problem.
Subject(s)
Animals, Wild , Cyanobacteria , Harmful Algal Bloom , Poisoning/veterinary , Water Pollutants/poisoning , Animals , Female , Male , Perissodactyla , Poisoning/mortality , South Africa , Water MicrobiologyABSTRACT
Whilst lead poisoning in raptors, scavenging birds and waterfowl is well studied and common knowledge, there is surprisingly little literature detailing the risk to mammalian scavengers and captive carnivores fed hunted meat. This case report describes the death of two captive cheetahs (Acinonyx jubatus jubatus) following acute onset of nervous symptoms. Clinical signs included hyper-excitability, seizures, arched back, tail held abnormally high and hyper-salivation. Necropsy findings included bullets or a bullet in their stomachs. Kidney and liver lead levels from one cheetah (15.6 ppm and 17 ppm respectively) were consistent with a diagnosis of lead poisoning; liver from the second cheetah was not available for testing. Both animals were routinely fed hunted antelope or game birds. This is the first report of oral lead poisoning in captive large carnivores, although these are unlikely to be the first cases. Without awareness of the risks of feeding hunted game, lead exposure will continue to be an underdiagnosed reality in the rehabilitation of endangered carnivores.
Subject(s)
Acinonyx , Animals, Zoo , Food Contamination/analysis , Lead Poisoning/veterinary , Meat/analysis , Animals , Female , Lead Poisoning/etiology , Male , South AfricaABSTRACT
The objective of this study is to identify levels of risk awareness for breast, lung and cervical cancer, in a UK student population. A sample of male (N=62) and female (N=58) university students, mean age 21.62 years completed a questionnaire identifying which risk factors they knew for each cancer. Analysis of variance was used to compare differences in risk awareness across gender and cancer types. Risk factor awareness was highest for lung cancer (0.78), mid-range for breast cancer (0.61) and lowest for cervical cancer (0.47). Women had greater risk factor awareness (0.67) than males (0.57) across all three cancers. There is also significant belief in mythic risk factors such as stress (from 14 to 40% across the three cancers). Previous research has demonstrated that risk factor awareness increases with educational status, yet even in a university student population, in which the majority of females would have been offered the HPV vaccination, risk factor awareness for cancers is variable. More health education is needed particularly around the risk factors for cervical cancer.