- Following the identification of the three main aspects of animal biosecurity in this context (monitoring, research, and intervention), we broadly identified two major users: government institutions and researchers.
- Usage by private entities such as pet owners and stores, zoos etc are being researched more to identify if there is a noticeable usage or need.
- We sought to identify where the use of a diagnostic device lied in these realms.
- Where in the monitoring efforts do government institutions utilize diagnostic devices?
- Live animal imports Animal/pet trade
- Which bodies utilize a diagnostic device?
- To aid in engineering the product: how is a diagnostic device utilized in their activities? Where is it not but can be?
- Where in their research does data collected from a diagnostic device come in?
- How often are those use cases noticed in literature and ongoing research?
- To aid in engineering the product: how is a diagnostic device utilized in their activities? Issues with current methods
- Ensuring biosecurity for wildlife diseases has numerous conversations in the scientific community leading to toolboxes/strategies to effectively bridge science and management.
- As can be seen in the main team board, the role of governments is strongly tied to different stages of handling infectious wildlife diseases.
- Based on (Langwig et al., 2015)'s work, we divided our user mapping process using three stages based on differences in disease dynamics and appropriate management actions: Pre‐arrival, Invasion front, Epidemic/Established.
- "Identifying the invasion stage of the pathogen in a region requires data on host abundance and pathogen prevalence, making the initial collection of these data a critical part of disease management." (Langwig et al., 2015)
- We hope to map the different stages of an intervention to the activities carried out by different institutions and government entities.
- The identified usage of a diagnostic device in animal biosecurity are the following:
- Active testing as part of risk assessment
- Pre-import testing
- Personal usage by pet owners, stores, and zoos
- Testing as part of prevention using host culling
- Disease prevalence test during invasion front
- Disease prevalence test during epidemic
- The pre-arrival stage is one of caution where a given disease could potentially spread to a given area. In the case of the Bsal and Bd for instance, even though cases have not reached an alarming rate in most parts of Europe, models indicate areas are susceptible to spread pending physical spread and climatic conditions amongst other reasons. Amphibian Decline Import restrictions, monitoring of target species, and pubic engagement are actions that could be taken during this first stage. (Langwig et al., 2015)
- In the pre-arrival stage, we identified that most of the usage is by researchers working to assess the risk of the disease by identifying prevalence spread.
- After collecting sample from a live animal, the amphibian is released at the point of capture. (Tarrant et al., 2013) The addition of a field use device at this stage would thus not contribute to biosecurity, besides perhaps to convenience. Stakeholders will be queried to see if they would be keen on not releasing animals if the diagnostic method gave quick results.
- A potential method of advancement for a fully functional diagnostic device is through international membership organizations that have under their mandate reporting of diseases.
- Active testing as part of risk assessment:
- Unless part of a mandated risk assessment in the wake of cases/symptoms, there doesn't seem to be any case of frequent testing (monitoring) to ensure a habitat/species has been compromised.
- Pre-import testing
- The European Food Safety Authority has found that enacting legislation that requires testing of the animals to demonstrate freedom from Bsal, before movement can take place, complemented with other measures such as quarantining, tracking and public awareness are possible risk mitigation measures to ensure sage international and EU trade of salamanders and their products. (EFSA et al., 2017)
- The OIE has set principles and methods of validation of diagnostic assays for infectious diseases that need to be fulfilled for acceptance and usage in regulations. (OIE, 2019)
- An assay that has completed the first three stages of the validation pathway (figure above), including performance characterization, can be designated as “validated for the original intended purpose(s) and become accepted by the OIE.
- Currently, the OIE only has clinical signs and behavioral changes listed under field use methods.
- Some of the mitigation measures proposed by (Grant et l., 2017) and evaluated by (EFSA et al., 2017) as ineffective have their roots in a lack of quick response which could potentially be enhanced with a diagnostic device.
[Quarantine] measures could be applied for both imports into the EU and intra-EU movements. The recommended duration of quarantine is 6–8 weeks during which the salamanders are to be sampled by skin swabs and tested by PCR assay at the beginning and the end of quarantine, although the test, at this point in time, has not been yet validated and the uncertainty related to its performance is very high. (EFSA et al., 2017)
- When testing a conignment of amphibians during import or assessment, ensuring high confidence (95%) with worst-case DSe identified by (EFSA et al., 2017) (0.5) needs large sample sizes from the consignment.
- Our diagnostic device could thus improve the process in two ways: increase the sensitivity and specificity (requiring lower sample sizes) or have a comparable detection metrics to current methods but output results at a much lower turnover time.
- Discussion from Dr. Penner indicates that host culling is not actively sought for Bd and Bsal. However, some of that non-relaince of host culling as a containment major has to do with the unrelaiblity of current diagnostic methods.
- Dr. Penner also confirmed that there would be an added advantage to a rapid field use device besides convenience since the researchers would then have the option of not releasing infected animals back into the habitat.
- Beyond managing the diagnostic techniques, Dr. Penner pointed out that additional skills are required for finding and identifying animals in the wild.
- Active surveillance is carried out varyingly amongst nations and governing bodies. The government of Germany, for example, only takes an active role with diseases related to birds and mammals. Amphibian and reptile diseases are analysed by researchers.
- Given the other elements of this stage (testing, quarantine, and banning), Dr. Penner indicated that the cost of testing as a limitation for the biosecurity measures in trade is high.
... there are "waves" of higher rates of testing and lower efforts but not really continuous comparable standardized monitoring. Your machine could enable that. Dr. Penner User Mapping Questions
- The EPA (US Environmental Protection Agency) states high costs, some requiring sacrificing animals, others being invasive but nonlethal, while only a few being noninvasive to recommend laboratory investigations be considered on a higher-order or tier than routine bioassessments.
- Why PCR?
- Several diagnostic methods for Bsal detection have been described including histology/histopathology, PCR, qPCR, and lateral flow technology. However, the limitations of some of these techniques include (i) the need for experienced operators or experts to perform these assays, (ii) the ability of the tests to only detect and not quantify the pathogen in samples, (iii) the inability to detect low numbers of the pathogen and (iv) poor diagnostic sensitivity and specificity. The Bsal real-time PCR adequately addresses these limitations and is one of the premier methods for Bsal diagnostics in use. (Thomas et al, 2017)
Takeaways from Dr. Langwig interview:
- One issue with culling during pre-arrival (and culling in general) is that if the outbreak is much more widespread than your sampling, culling will be ineffective. However, if the spread is very localized, then knowing which animals are infected during pre-arrival would be helpful. Faster tests will always allow faster decisions.
- Most of the time, the complications [with field work in collecting sample] come from being to accurately identify the species and catch and hold the animal appropriately as opposed to collecting the sample (which in our case is just a swab).
- Sometimes researchers are leading the charge to collect samples, as has often been the case for chytridiomycosis. For other pathogens, sampling is more routine, usually conducted by government employees, often with more coordinated oversight by a central government.
- Testing might be cheaper than implementing trade bans, depending on the product and specific risk. For example, the U.S. banned salamander imports, and while I don't know specific dollar amounts, I suspect the importation of salamanders to the U.S. is not generating a lot of value. (Dr. Karen Lips at U of Maryland was involved in this, and might be a good person to contact.) Therefore, banning salamander imports might be worth the cost tradeoff of testing every salamander. For something where profits were higher, I would think testing could be far more beneficial then costs associated with reductions in trade or sanitizing equipment.
Takeaways from Dr. Penner:
- No, culling is not a strategy currently promoted for Bd or Bsal. This has several reasons. Partly because diagnostics are never 100% reliable. Partly because this will not stop the spread of the disease because it is also transmitted by other vectors (i.e. other species and other means (e.g. soil, water). Testing all vectors is impossible. For Bd and BSal other researchers test avenues to cure the infected individuals, which looks promising in the case of Bsal. So the current idea is to remove infected individuals, keep them in captivity until free of the pathogen, monitor the environment until pathogen free as well, then release the individuals back into the wild.
- [If diagnostic were to be improved], researchers would be faster and would not release infected animals. These would not be culled but cured and released at a later point in time. This is not possible with current methods. One has to wait until infections have spread widely, then find living animals which will all be collected (not only infected individuals) and treated in captivity until release.
- Currently researchers [collect samples] but in case this will prove to be a reliable method, hired personnel would most likely be included as well.
- Currently, the government in Germany only takes an active role in diseases related to birds and mammals. Amphibian and reptile diseases are analyzed by researchers.
- Q: One of the barriers to a rigorous measure during the pre-arrival stage is the significant cost and impact on trade. (Langwig et al., 2015) Given the other elements of this stage (testing, quarantine, and banning), how significant is the cost of testing as a limitation for the biosecurity measures?
- In my opinion, costs are significant because research is conducted on the basis of money acquired by third-party funds. Thus limited and only available for specific projects. Thus there are "waves" of higher rates of testing and lower efforts but not really continuos comparable standardized monitoring. Your machine could enable that.