In veterinary work surveillance is the term for a structured approach to monitoring the health status of an animal population for the purposes of managing the risks associated with infections in the targeted population. It can be seen from the broad objectives of surveillance
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listed here that the risks managed may be broadly inclusive of risks to the profitability of enterprises as well as risks to the national economy or society as a whole.
Surveillance can be conducted for the purposes of:
early detection of animal disease to facilitate control
early detection of genetic changes in infectious agents that alter the risks to human or animal health
early detection of phenotypic changes (antigenic match to available vaccines, antiviral susceptibility) with implications for human or animal health
assessment and management of disease control programs
improved knowledge of infectious disease agent epidemiology and disease pathogenesis
monitoring the performance of diagnostic tools
Given the potential benefits to be derived the question arises as to why surveillance is not already a standard or more widely adopted management practice in animal agriculture.
However surveillance costs money, and, importantly, is best conducted where there is an agreed, effective, scientifically rational and financially proportionate response to the findings.
A recent World Bank paper has explored these aspects in more detail (World Bank, 2010).
In broad terms surveillance may not be undertaken because of an inability to do so, or an unwillingness to do so. Inabilities to detect may be associated with lack of awareness of the process, or be more technically based around a lack of sampling and testing capacity.
Concurrently there may be no established reporting and response chain. In the last decade there has been marked developments in understanding of EIDs, the ability of the veterinary services to engage with such matters and the capacity of laboratories to provide testing capability. There is no reason to think that there are insurmountable challenges in the ability to do surveillance in countries that are able to engage in the commercial activity of intensification of animal husbandry.
It follows that any sub-optimal engagement in effective surveillance arises from a lack of willingness to engage in the activity, and there are persuasive reasons why this would be the case. Cost is one factor, including lack of any clear financial advantage and also lack of any mechanism of cost recovery. Importantly, if the activity is not conducted in a well planned and communicated policy setting, there can be inappropriately managed negative consequences. At the international level there can be trade restrictions, nationally there may be movement bans on live animals or animal products, in some cases there may be compulsory slaughter (with or without compensation) and also at the consumer level there may be loss of market or market share if the communications are not well handled. And there must be communication of the findings, surveillance can‘t be conducted in secret since the purpose is to provide the information upon which informed and well communicated responses can be based.
A prerequisite for surveillance for the better identification and management of public health threats arising in farmed animals is a process of consultation among those likely to respond to findings as well as those likely to be involved in the implementation of the activity.
There are certain key issues to recognize, and then to address.
Who will carry the cost of this surveillance, and any response to the findings? It might be thought that ultimately it should be the consumer, but what will be the mechanism by which the producer can recoup the costs in a price sensitive market? If the consumer is to be sufficiently well informed to want to pay a small margin for a safer product we might expect
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that the issues will have to be publicly debated, as are other animal production issues such as animal welfare, antibiotic sensitivity and the putative health benefits of different types of foods.
Secondly, is the scientific basis for the concerns, and particularly for the responses, sufficiently well developed? Can a public health threat be objectively defined, or even a pandemic threat? Agreement is needed in advance upon which findings will be associated with specified levels of response, otherwise the risk of disruption to business continuity through ill conceived or ―knee jerk‖ reactions by regulatory authorities will be sufficient to preclude farmer cooperation. Regulation can be expected to have a role in the process, but regulations that are science based and arrived at through the processes of public-private industry consultation.
Conclusions
If surveillance of farmed animals is to become a normal part of the way business is done then it will be on the basis that an informed public understands the risks and the proposed mitigation steps, and that industry feels confident that the measures in place under the auspices of both public and animal health authorities are science based, well thought through, appropriately costed and effectively manage real risks rather than apprehensions.
The frequency with which new EIDs are being detected, causing deaths of people who were not previously at risk, clearly indicates that the time for these serious discussions has certainly arrived.
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