DATA FLOWS WITHIN THE EMERGENCY HEADQUARTERS

The emergency headquarters (EHQ) is the field operations control centre during the

eradication campaign. It is intended to be as close as possible to the infected places (IPs) to facilitate the directing of control procedures. A key consideration during the design of the EpiMAN system was to construct the database such that a complete national “picture” would be available at the EHQ. This entailed having the computing resources sufficient for this at the EHQ, and assigning the necessary responsibilities to the managers of the various sections. The EHQ is divided into a number of operational sections, responsible for particular roles in the eradication programme (see Figure 1.8).

MAF Policy specifications require that the EHQ be operational within 24 hours of the

emergency being declared (NASS, 1991). Its immediate task is to assume responsibility for all actions initiated by the exotic disease response manager (EDRM) in the region of the outbreak during the transitional period. These include slaughter and disinfection of the initial IP(s), urgent tracing of all high risk movements associated with the IP(s), investigations on contiguous properties and all garbage piggeries in the IA, and any other properties deemed to be high-risk or possible sources. An ERP 12 form (see Appendix 3) records details of the findings of the investigating veterinarian on the first IP. Any subsequent IPs are reported on ERP 13 forms - Farm Status Report (commonly known as “telephone reports” because the information is relayed in from the farm by telephone - see Appendix 3). These telephone reports therefore become one of the most important documents in the eradication campaign. Figure 3.1 portrays the major data flows and processes in the EHQ following the receipt of a Farm Status Report.

The telephone report conveys the patrol veterinarian's findings to the EHQ. It is designed to report on IPs, suspect premises (SPs) and pre-emptive slaughter premises (PESPs). SPs are properties where suspicious lesions have been discovered, but the investigating veterinarian in consultation with the DIGM feels that there is sufficient doubt to justify leaving the farm until its status is clarified. Usually the farm would be revisited to allow time for the situation on the farm to progress, or a second opinion requested. PESPs (also known as dangerous-contact slaughter premises) are farms that have been directly or indirectly in contact with an IP, such that it is believed there is high probability that infection is present on the farm and that the risks of further spread are sufficient to justify the slaughtering of the exposed animals.

The telephone report is divided into two main sections. Section ERP 13A is entitled “Farm Status - Initial Report” and contains the initial findings on the IP, and also relays needed information on SPs and PESPs. On receipt of the information at the EHQ, the data is entered into the DBMS via input forms on the computer terminal. The IP support group (IPSG) is automatically notified of each

the farm and the farm profile information, as well as information regarding access to water, power and telephone at the main entrance. This allows the IPSG to begin their tasks in terms of gate security, slaughter and disposal of stock, and cleaning and disinfection (C&D). Additional processes that section ERP 13A initiates are the imposition of standstill controls on contiguous properties and any other properties belonging to the owner, and urgent tracing of any movements of susceptible animals off the property that have occurred during the period prior to diagnosis. These latter processes are conducted for all three farm disease classifications. If a negative diagnosis is ultimately made on a SP, any standstills applied are lifted.

Section ERP 13B is headed “Farm Status - Final Report” and contains details of the remainder of the investigation when infection is confirmed. It includes livestock numbers by species, morbidity data, a clinical report, an assessment of the origin of the disease, details of all previously unlisted movements on to or off the farm since the introduction of virus on to the property (age of oldest lesions plus incubation period) and source of any garbage fed to animals.

On receipt of information relating to section ERP 13B at the Disease Investigation Group (DIG), the on-farm FMD virus production model (FMDVPM) is run using details of the clinical report as input (Chapter 4). This model recreates the buildup of infection on the farm and quantifies virus release to the atmosphere, and into milk in the case of dairy farms. Outputs are written to database files, which are then accessible by the rest of the system.

All movement information is analyzed by the tracing expert system (Chapter 5), and tracing tasks are ranked in priority order. The movement information is then processed by the Tracing Group (TG). This involves tracing each “conveyor” to its logical conclusion by telephoning the people

involved. By “logical conclusion” is meant that the items have been traced to a final destination, or that they have been rendered safe through some procedure such as a contaminated truck having adequate C&D.

Consider a group of susceptible animals that were transferred from the IP to property B. The person who transported the animals off the IP would be contacted to find out where the animals were delivered to, and what further “encounters” were experienced en route. The owner of property B would then be telephoned to confirm that the animals were received. If it was found that the animals had been present, but were since shifted to property C, then this new trace is investigated. This process records encounters, which are opportunities for conveyors to transmit FMDV to another conveyor or to a farm (see Chapter 5 for further details).

processing establishments, herd improvement centres (AI technicians), veterinary practitioners etc. (NASS, 1989). Each property that is identified as at risk due to the movement of animals, persons, products or fomites (vehicles, plant and equipment) has a Patrol Form (ERP 14) (see Appendix 3) generated. Each vehicle used to transport possibly infectious items is identified and a C&D Order (Appendix 3) form issued.

The DIGM is responsible for overseeing the surveillance of all farms exposed to risk of FMD. These include:

• contiguous properties;

• livestock units within a 3 km Patrol Zone;

• other properties associated with the IP such as run-offs;

• premises involved in encounters with potentially infective conveyors; • livestock units exposed to windborne plumes of FMDV.

These premises are identified directly off the Farm Status Report, as a result of TG investigations, by the epidemiologist and the meteorologist associated with the EHQ in the case of airborne spread, and by the GIS in association with the mapping officer in the case of farms within the Patrol Zone. All at-risk premises are stored in an AT-RISK file, with each individual episode or situation that places a farm at risk being itemised in the EPISODES table (see Appendix 2). Details of each at-risk property are printed on a Patrol Form.

The Patrol Forms are assessed by the DIGM who decides if field investigations are required. Information presented to the DIGM includes the date and nature of all episodes that place the property at risk, a summary risk rating, the earliest date one would expect to see clinical signs if disease were to become established, and the date by which the event can be discounted if no clinical signs appear. This information is furnished by the expert system (see Chapter 5). If a field investigation is warranted, then a visit date is assigned based on this information. The DIGM assigns farms to be visited to the

available patrol veterinarians. A copy of the Patrol Form is generated for each day that a farm is scheduled for a visit. The patrol veterinarians record their investigational findings on the form, update any details such as name of owner/manager, animal numbers etc., enter the period of time taken to examine the animals on the farm and return the form to the EHQ at the end of the day. Data entry personnel enter the information off these reports into the database during the evening. If a particular veterinarian is unable to complete his/her quota of visits for the day, then the DIGM is notified who arranges for a reserve veterinarian to complete the investigation(s).

If the DIGM is satisfied that there is no infection on a farm, the farm is deleted from the AT- RISK file, otherwise a revisit date is set. Farms generally remain active on the AT-RISK file until 14

days have elapsed since the last exposure incident (episode) without the appearance of clinical signs, the generally recognised period of maximum incubation for FMD (Garland & Donaldson, 1990). If infection is discovered, a new Farm Status Report is generated, which initiates another cycle of investigations.

If a farm which requires investigation is outside the Infected Area (IA), the DIGM forwards the details to the EDRM in the region involved. The animal health laboratory is termed the Regional Emergency Centre (REC) during the campaign, and performs as a “satellite” EHQ. The REC conducts any investigations necessary, and reports back to the EHQ.

Vehicles identified as possibly contaminated with FMDV are the responsibility of the Movement Control Group Manager (MCGM). C&D Order forms are generated as a result of the tracing process. The C&D Order number is relayed to the vehicle driver, who is directed to proceed to the most suitable C&D site. A copy of the C&D Order is then sent to the C&D site. Once supervised C&D has been completed, the C&D Order form is signed by the Inspector manning the C&D site. If the vehicle is outside the IA, then the MCGM notifies the appropriate REC, which is then required to report back to the EHQ. The date of issuance of the C&D Order is stored in the DBMS, and a bring-up system operates to allow checking whether vehicles have been dealt with. If the driver or owner of the vehicle fails to present the vehicle at the C&D site, the C&D Order will be delivered in person, using a Police officer if necessary.

In addition to the responsibility for C&D of all contaminated vehicles, the Movement Control Group (MCG) operate a permit system for the movement of animals, products or equipment within the IA. People in the IA are required to contact the MCG for permission prior to movement of any of these items. The MCG staff first consult a standstill file, which is a list of all SPs, IPs and at-risk farms, to check if the farm in question is included as a dangerous property. If the farm is listed, a standstill order applies against the property and permission will be denied. If the farm is not listed, a free-movement schedule is referred to, to find out which classes of items (and with what conditions) can be moved within the IA. This list is maintained by the EHQ Controller, who revises it periodically as

epidemiological details about the epidemic emerge. Where permission is granted, a Movement Permit (see Appendix 3) is issued. If one of the conditions is that the vehicle involved in transport requires subsequent C&D, then a C&D Order will be issued concurrently.

While investigations are proceeding, the IP which generated the Farm Status Report is

undergoing valuation, slaughter and disposal of susceptible livestock, and C&D of the premises. An IP Manager is appointed on the site, and notifies the Infected Place Support Group Manager (IPSGM) at the EHQ on progress. Once C&D is complete, an IP Clearance Order is signed, and the details entered into the DBMS. A tentative date of limited restocking is set, approximately 6 weeks after C&D is

render the risk of reinfection too high to allow restocking.