Validity and reliability of telephone administration of the patient-specific functional scale for the assessment of recovery from snakebite envenomation

OBJECTIVES: Although more than 1.8 million people survive snakebite envenomation each year, their recovery is understudied. Obtaining long-term follow-up is challenging in both high- and low-resource settings. The Patient-Specific Functional Scale (PSFS) is an easily administered, well-accepted patient-reported outcome that is validated for assessing limb recovery from snakebite envenomation. We studied whether the PSFS is valid and reliable when administered by telephone. METHODS: This is a secondary analysis of data from a randomized clinical trial. We analyzed the results of PSFS collected in-person on days 3, 7, 14, 21, and 28 and by telephone on days 10, 17, and 24. We assessed the following scale psychometric properties: (a) content validity (ceiling and floor effects), (b) internal structure and consistency (Cronbach\u27s alpha), and (c) temporal and external validity using Intraclass Correlation Coefficient (ICC). Temporal stability was assessed using Spearman\u27s correlation coefficient and agreement between adjacent in-person and telephonic assessments with Cohen\u27s kappa. Bland Altman analysis was used to assess differential bias in low and high score results. RESULTS: Data from 74 patients were available for analysis. Floor effects were seen in the early post-injury time points (median: 3 (IQR: 0, 5) at 3 days post-enrollment) and ceiling effects in the late time points (median: 9 (IQR: 8, 10). Internal consistency was good to excellent with both in-person (Cronbach α: 0.91 (95%CI 0.88, 0.95)) and telephone administration (0.81 (0.73, 0.89). Temporal stability was also good (ICC: 0.83 (0.72, 0.89) in-person, 0.80 (0.68, 0.88) telephone). A strong linear correlation was found between in-person and telephone administration (Spearman\u27s ρ: 0.83 (CI: 0.78, 0.84), consistency was assessed as excellent (Cohen\u27s κ 0.81 (CI: 0.78, 0.84), and Bland Altman analysis showed no systematic bias. CONCLUSIONS: Telephone administration of the PSFS provides valid, reliable, and consistent data for the assessment of recovery from snakebite envenomation

Snakebite: An Exploratory Cost-Effectiveness Analysis of Adjunct Treatment Strategies.

The cost-effectiveness of the standard of care for snakebite treatment, antivenom, and supportive care has been established in various settings. In this study, based on data from South Indian private health-care providers, we address an additional question: "For what cost and effectiveness values would adding adjunct-based treatment strategies to the standard of care for venomous snakebites be cost-effective?" We modeled the cost and performance of potential interventions (e.g., pharmacologic or preventive) used adjunctively with antivenom and supportive care for the treatment of snakebite. Because these potential interventions are theoretical, we used a threshold cost-effectiveness approach to explore this forward-looking concept. We examined economic parameters at which these interventions could be cost-effective or even cost saving. A threshold analysis was used to examine the addition of new interventions to the standard of care. Incremental cost-effectiveness ratios were used to compare treatment strategies. One-way, scenario, and probabilistic sensitivity analyses were conducted to analyze parameter uncertainty and define cost and effectiveness thresholds. Our results suggest that even a 3% reduction in severe cases due to an adjunct strategy is likely to reduce the cost of overall treatment and have the greatest impact on cost-effectiveness. In this model, for example, an investment of $10 of intervention that reduces the incidence of severe cases by 3$75 per individual. These findings illustrate the striking degree to which an adjunct intervention could improve patient outcomes and be cost-effective or even cost saving

Histopathological analysis and in situ localisation of Australian tiger snake venom in two clinically envenomed domestic animals

Objective: To assess histopathological changes in clinically envenomed tiger snake patients and identify tissue specific localisation of venom toxins using immunohistochemistry. Samples: One feline and one canine patient admitted to the Murdoch Pet Emergency Centre (MPEC), Murdoch University with tiger snake (Notechis sp.) envenoming. Both patients died as a result of envenomation. Non-envenomed tissue was also collected and used for comparison. Methodology: Biopsy samples (heart, lung, kidney andskeletal muscle tissue) were retrieved 1-2 h post death and processed for histopathological examination using Haemotoxylin and Eosin, Martius Scarlet Blue and Periodic Acid Schiff staining. Tissues were examined by light microscopy and tissue sections subjected to immunohistochemical staining using in-house generated monoclonal and polyclonal antibodies against Notechis venoms. Results: Venom-induced pathological changes were observed in the lungs, kidneys and muscle tissue of both patients. Evidence, not previously noted, of procoagulant venom effects were apparent, with formed thrombi in the heart, lungs (small fibrillar aggregates and larger, discrete thrombi) and kidneys. Immunohistochemical assays revealed venom present in the pulmonary tissue, in and around the glomerular capsule and surrounding tubules in renal tissue and scattered throughout the Gastrocnemius muscle tissue. Conclusion: This work has shown pathological evidence of procoagulant venom activity supporting previous suggestions that an initial thrombotic state occurs in envenomed patients. We have shown that venom toxins are able to be localised to specific tissues, in this case, venom was detected in the lung, kidney and muscle tissues of clinically envenomed animals. Future work will examine specific toxin localisation using monoclonal antibodies and identify if antivenom molecules are able to reach their target tissues

Global mortality of snakebite envenoming between 1990 and 2019

Snakebite envenoming is an important cause of preventable death. The World Health Organization (WHO) set a goal to halve snakebite mortality by 2030. We used verbal autopsy and vital registration data to model the proportion of venomous animal deaths due to snakes by location, age, year, and sex, and applied these proportions to venomous animal contact mortality estimates from the Global Burden of Disease 2019 study. In 2019, 63,400 people (95% uncertainty interval 38,900–78,600) died globally from snakebites, which was equal to an age-standardized mortality rate (ASMR) of 0.8 deaths (0.5–1.0) per 100,000 and represents a 36% (2–49) decrease in ASMR since 1990. India had the greatest number of deaths in 2019, equal to an ASMR of 4.0 per 100,000 (2.3—5.0). We forecast mortality will continue to decline, but not sufficiently to meet WHO’s goals. Improved data collection should be prioritized to help target interventions, improve burden estimation, and monitor progress

Pliocercus

Number of Pages: 9Integrative BiologyGeological Science

An Integrated Assessment of the Introduction of Lionfish (Pterois volitans/miles complex) to the Western Atlantic Ocean.

Lionfish (Pterois volitans/miles complex) are venomous coral reef fishes from the Indian and western Pacific oceans that are now found in the western Atlantic Ocean. Adult lionfish have been observed from Miami, Florida to Cape Hatteras, North Carolina, and juvenile lionfish have been observed off North Carolina, New York, and Bermuda. The large number of adults observed and the occurrence of juveniles indicate that lionfish are established and reproducing along the southeast United States coast. Introductions of marine species occur in many ways. Ballast water discharge, a very common method of introduction for marine invertebrates, is responsible for many freshwater fish introductions. In contrast, most marine fish introductions result from intentional stocking for fishery purposes. Lionfish, however, likely were introduced via unintentional or intentional aquarium releases, and the introduction of lionfish into United States waters should lead to an assessment of the threat posed by the aquarium trade as a vector for fish introductions. Currently, no management actions are being taken to limit the effect of lionfish on the southeast United States continental shelf ecosystem. Further, only limited funds have been made available for research. Nevertheless, the extent of the introduction has been documented and a forecast of the maximum potential spread of lionfish is being developed. Under a scenario of no management actions and limited research, three predictions are made: ● With no action, the lionfish population will continue to grow along the southeast United States shelf. ● Effects on the marine ecosystem of the southeast United States will become more noticeable as the lionfish population grows. ● There will be incidents of lionfish envenomations of divers and/or fishers along the east coast of the United States. Removing lionfish from the southeast United States continental shelf ecosystem would be expensive and likely impossible. A bounty could be established that would encourage the removal of fish and provide specimens for research. However, the bounty would need to be lower than the price of fish in the aquarium trade (~$25-$50 each) to ensure that captured specimens were from the wild. Such a low bounty may not provide enough incentive for capturing lionfish in the wild. Further, such action would only increase the interaction between the public and lionfish, increasing the risk of lionfish envenomations. As the introduction of lionfish is very likely irreversible, future actions should focus on five areas. 1) The population of lionfish should be tracked. 2) Research should be conducted so that scientists can make better predictions regarding the status of the invasion and the effects on native species, ecosystem function, and ecosystem services. 3) Outreach and education efforts must be increased, both specifically toward lionfish and more generally toward the aquarium trade as a method of fish introductions. 4) Additional regulation should be considered to reduce the frequency of marine fish introduction into U.S. waters. However, the issue is more complicated than simply limiting the import of non-native species, and these complexities need to be considered simultaneously. 5) Health care providers along the east coast of the United States need to be notified that a venomous fish is now resident along the southeast United States. The introduction and spread of lionfish illustrates the difficulty inherent in managing introduced species in marine systems. Introduced species often spread via natural mechanisms after the initial introduction. Efforts to control the introduction of marine fish will fail if managers do not consider the natural dispersal of a species following an introduction. Thus, management strategies limiting marine fish introductions need to be applied over the scale of natural ecological dispersal to be effective, pointing to the need for a regional management approach defined by natural processes not by political boundaries. The introduction and success of lionfish along the east coast should change the long-held perception that marine fish invasions are a minimal threat to marine ecosystems. Research is needed to determine the effects of specific invasive fish species in specific ecosystems. More broadly, a cohesive plan is needed to manage, mitigate and minimize the effects of marine invasive fish species on ecosystems that are already compromised by other human activities. Presently, the magnitude of marine fish introductions as a stressor on marine ecosystems cannot be quantified, but can no longer be dismissed as negligible. (PDF contains 31 pages