Đề tài Development of Improved Capabilit Cattle and Pigs - Milestone 8

Ministry of Agriculture & Rural Development Development of Improved Capability in Support of National Biosecurity for the Surveillance and Control of Foot & Disease in Cattle and Pigs FMD Vaccine Efficacy Testing and FMD Vaccination Recommendations § Milestone 8 Resubmission, June 2010 Milestone 8 Chris Morrissy Mouth § 1 Table of Contents 1. Institute Information ____________________________________________ 2 2. Project Abstract ________________________________________________ 3 3. Executive Summary ____________________________________________ 3 4. Progress to date _______________________________________________ 4 4.1 Implementation Highlights [FMD vaccine efficacy testing and FMD vaccination recommendations] ___________________________________ 4 5. Conclusions ___________________________________________________ 8 2 1. Institute Information Project Name CARD FMD [072/04VIE] Vietnamese Institution Regional Animal Health Centre (RAHO-6) Ho Chi Minh City South Vietnam Vietnamese Project Team Leader Dr Dong Manh Hoa Australian Organisation Australian Animal Health Laboratory [AAHL] Private Bag 24 Geelong, VIC 3220 Australia Australian Personnel Mr Chris Morrissy Date commenced 01/06/2005 Completion date (original) 01/06/2008 Completion date (revised) Reporting period Completed following project completion Contact Officer(s) In Australia: Team Leader Name: Mr Chris Morrissy Telephone: +61 3 5227 5000 Position: Supervisor Mammalian Virology Fax: +61 3 5227 5555 Organisation Australian Animal Health Laboratory [AAHL] Private Bag 24 Geelong, VIC 3220, Australia Email: chris.morrissy@csiro.au In Australia: Administrative Contact Name: Mr Christopher Morrissy Telephone: +61 3 5227 5434 Position: Patents Contracts Officer Fax: +61 3 5227 5555 Organisation Australian Animal Health Laboratory [AAHL] Private Bag 24 Geelong, VIC 3220 Australia Email: christopher.morrissy@ csiro.au In Vietnam Name: Dr Dong Manh Hoa Telephone: + 84 8 8568220 Position: Director Fax: + 84 8 8569050 Organisation Regional Animal Health Centre (RAHO-6) Ho Chi Minh City South Vietnam Email: rahchcmc@hcm.vnn.vn 3 2. Project Abstract The aims of this project were to develop capacity for FMD surveillance and diagnosis at both a laboratory and field level within the wider animal health network in Vietnam. Improved diagnostic capacity will facilitate the early detection and identification of FMD enabling better disease control. Specifically, successful capacity development at regional laboratories will enable quality assured laboratory capability for FMDV diagnosis and serology. This will be applied to the investigation of FMDV serotypes currently in circulation and the reason underlying on-going FMD vaccine failures in Vietnam. In addition, the successful establishment of an effective laboratory network for the diagnosis and control of FMD will provide a greater understanding of FMD epidemiology and will facilitate the coordination and implementation of effective vaccination control strategies via the wider animal health network in Vietnam. 3. Executive Summary Significant progress has been made in relation to the achievement of Milestone 8 objectives. Specifically, the acquisition of a database of FMD isolates which has enabled an evidence-based assessment of the prevalence and risks associated with individual FMD serotypes in specific regions. This has further facilitated ongoing surveillance which has demonstrated continual improvement in relation to FMD vaccine coverage in the field. Of particular significance, two-way communication, support and collaboration between the RAHO-6 laboratory and field veterinarians has facilitated highly effective disease diagnosis, surveillance and control. This has resulted in highly informed science-based recommendations being made to Department of Animal Health (DAH), field veterinarians and farmers with regard to the selection of the most appropriate FMD vaccine serotype formulations to be used in the field. The effectiveness of this approach is clearly evident from the fact that in southern Vietnam the incidence of FMD outbreaks has fallen continuously during the course of the project with only one isolated outbreak being reported in the 2009-2010 reporting period. A central aim of this project was to “highlight the importance of having a laboratory network to identify what is happening in the field and how to prevent and control disease outbreaks”. Of particular relevance, in relation to Milestone 8 deliverables, this project has not only successfully achieved this objective in southern Vietnam but of equal significance has further highlighted the difficulties anticipated at the outset of this project with regard to the logistics associated with effective FMD surveillance and control strategies in the field on a national level. Milestone 8 objectives have been achieved as a result of successful capacity development in the field of FMD diagnostic capability in Vietnam. For example, the establishment of full FMD diagnostic capability at both RAHO-6 and NCVD has, since the initiation of this project, cumulated in their recognition as FMD Reference Laboratories in Vietnam. Nevertheless, it is clearly apparent, and foreseen at the initiation of this project, that a critical component is the close integration, support and communication required between the newly established FMD Reference laboratories, Regional Laboratories and related field veterinarians and DAH personnel. This is clearly illustrated by the implementation strategy at RAHO-6 where successful capability development and quality assurance in the laboratory was the driving force behind more effective training and education of field veterinarians in relation to effective FMD management practices in the field. This was undoubtedly an ambitious project and also subject to unforeseen circumstances such as AI and PRRSV outbreaks in the field. Nevertheless, Milestone 8 deliverables have been achieved to varying degrees throughout Vietnam and with tremendous success in southern Vietnam. 4 4. Progress to Date [In relation to Milestone 8 Deliverables] 4.1 Implementation Highlights [FMD vaccine efficacy testing and FMD vaccination recommendations] An earlier year-by-year breakdown detailing the FMD serotype[s] in circulation and the ongoing vaccination history in each province included in the study was given in the earlier Milestone 6 Report entitled; “Epidemiological and sero-surveillance programs operational”. In this Milestone 8 resubmission, each of the specific Milestone Deliverables are addressed. In addition, each of the specific comments made by the Referees are discussed in relation to the achievement of project objectives. • Database of FMD isolates in Vietnam, including incidence and risk assessment in target villages/districts Comprehensive FMD diagnostic capacity development at RAHO-6, NCVD, and also FMD Ag ELISA capability at RAHO-4 & 7, has enabled FMD diagnosis and both sero-surveillance and the characterisation of FMD field isolates. This used in conjunction with the successful implementation of the AAHL LP ELISA has facilitated the determination of vaccine efficacy. In addition, when used in combination with the AAHL 3ABC ELISA, which can differentiate vaccinated from infected animals, has allowed the incidence of FMD infection to be determined. Resultant surveillance data has led to a greater understanding of the incidence of specific serotypes in circulation in the field in Vietnam, the determination of the efficacy of vaccine coverage and has facilitated the identification of the risks associated with specific FMD serotypes in target areas in Vietnam. During the course of this project sero-surveillance, serotyping and vaccine efficacy data were collected and collated on an ongoing yearly basis. As an example, data collected for 2008 are given in Attachment 1. Spreadsheets of yearly data are available and are used by RAHO-6 and other laboratories as progressive baseline data from which the effectiveness of this project on completion can be determined and for future benchmarking. Taken as a whole, the data obtained during the course of this project has had a very significant impact in relation to the diagnosis, surveillance and control of FMD in Vietnam. For example, in the 2006/2007 period the sequencing and genotyping of FMD field isolates was performed and highlighted the occurrence of the following FMD serotypes in Vietnam: • Serotype O [3 topotypes] o Cathay o ME-SA (Pan Asia) o SEA • Serotype A o Thailand / Malaysa 97 5 • Serotype Asia 1 o Jiangsu-China 2005 [North and Central of Vietnam] o Myanmar 98 [Central Vietnam] Of particular significance, the ability of FMD Reference Laboratories in Vietnam to genotype FMD field isolates has already resulted in the refinement of vaccine usage in the field. For example, the results of this study have driven an evidence-based change in the serotype composition of FMD vaccine from A 22 to A Malaysia 97 with a concomitant change in the antigen used for serological tests in Vietnam. In addition, the inclusion of provinces with borders to Cambodia, Laos and China has further strengthened Vietnam’s biosecurity by detecting disease incursions [e.g. confirmation of 2 cases of FMD Asia 1 virus] of serotypes of FMD not previously detected in Vietnam. As requested by the Referees, presentations detailing the results of FMD outbreak investigations and serological surveys covering the period 2005-2008 have been attached to the earlier Milestone 10 Report. However, for convenience, the CARD FMD presentations given at the SEAFMD Lower Mekong Working Group in 2008 and further updated at the SEAFMD LabNet Meeting in 2010 are given as Attachments 2 and 3 to further substantiate this and subsequent Milestone 8 deliverables. For example, the effectiveness of FMD diagnosis and control measures as a result of this project are clearly evident from the year-by-year geographic breakdown of outbreaks in Vietnam and are given in Attachment 2. Specifically, the numbers of FMD outbreaks have progressively declined during the 2005-2008 period and of particular significance, there have subsequently been only one isolated FMD outbreak in South Vietnam in the 2009-2010 reporting period. These results clearly demonstrate the effectiveness of the coordinated laboratory diagnosis and disease surveillance conducted by RAHO-6 in relation to the FMD risk assessment, surveillance and subsequent control using the correct vaccine serotype composition and serotype specific serological tests in southern Vietnam. Specifically, the availability of sero-surveillance data in conjunction with direct contact and support of field veterinarians by RAHO-6 has led to increased vaccine coverage, an improved response to vaccination in cattle with resultant highly effective control of FMD in the southern provinces of Vietnam. • Results of efficacy testing Vaccine efficacy testing was performed using the AAHL LP ELISA for O, A22, A Malaysia and the Asia 1 serotype of FMDV. The results from vaccine efficacy testing demonstrated that the FMD vaccine response rate in cattle surveyed increased from 29% in 2006 to 68% in the second half of 2008 [Attachment 3]. In addition, the efficacy of vaccine coverage was greater on larger scale commercial cattle farms where a coverage rate of 90% was observed in 2008. In smaller farms, sero-surveillance of vaccine efficacy post-vaccination in cattle consistently demonstrated moderate vaccine coverage with an initial vaccination response of 60%. In addition, in all small-scale operations the vaccination response in pigs was much lower at 10%. However, as expected, commercial large-scale farms achieved a much higher vaccination response both in cattle (90%) and in pigs (70%). This is a reflection of the difficulties associated with vaccination on smaller farms where vaccination is not performed to the same level and where animal 6 identification and record keeping required for follow-up surveillance of individual animals is not as straightforward compared to larger scale commercial enterprises. However, the lower rate of vaccine coverage observed in all pig farms reflects not only the difficulties associated with animal identification on smaller farms but also the intrinsic lower immune response elicited post-vaccination of pigs. The results of vaccine efficacy testing and surveillance in the field have been highly successful in significantly reducing FMD outbreaks in southern Vietnam. However, as raised at the SEAFMD LabNet Meeting in 2010, this study also highlighted shortcomings in relation to how FMD surveillance is being conducted in areas outside southern Vietnam. Specifically, this project has highlighted the requirement for much greater communication and coordination on a national level between both DAH laboratory and field-based personnel. • Veterinarian and farmer vaccination recommendations Accurate vaccination recommendations to both veterinarians and farmers are essential for the diagnosis, surveillance and control of FMD in the field in Vietnam. During the course of this project, successful laboratory capacity development has resulted in the attainment of FMD Reference Laboratory status by both RAHO-6 and NCVD. This has facilitated FMD diagnosis and both the serotyping and genotyping of FMD field isolates required to enable an informed decision to be made in relation to the selection of the most appropriate and effective FMD vaccines in Vietnam and on a region-by-region basis. The successful implementation of FMD diagnostics, surveillance and control strategies has already resulted highly effective evidence-based recommendations being made by DAH in relation to the serotype composition of FMD vaccine to be used in the field. For example, the change from A 22 to A Malaysia 97 in Vietnam and the selection of regions that are recommended to use trivalent vaccines (serotype O, A & Asia 1) and those that are recommended to use divalent vaccines (either O & A or O and Asia 1). Of particular significance in relation to making vaccine recommendations to both veterinarians and farmers, RAHO-6 provides training and advice to other regional laboratories and DAH personnel in relation to proper sample collection for surveillance and virus serotype characterisation in the laboratory. The training comprised initial workshops conducted at the start of the project, on-going OIE workshops and highly effective on-the-job “hands-on” training of DAH personnel in the field during the course of the project. The successful reduction of FMD in southern Vietnam attests to the potential effectiveness of the approach adopted by RAHO-6 and the likelihood of success when applied in other areas in Vietnam in the future. However, notwithstanding this achievement, it is acknowledged that considerable work remains to be done elsewhere in Vietnam to ensure effective vaccination programs and vaccine recommendations. However, vaccine recommendations can only be substantiated following laboratory submission and characterisation of FMD field samples. 7 Specific comments made by the Reviewers 1. The earlier milestone 8 Report detailed the provinces that met submission requirements for each round but no data was included. o In this Milestone 8 resubmission an example of yearly returns is given as Attachment 1. As related earlier in this resubmission, all data collected are available as spreadsheets of yearly returns and are used as ongoing baseline data in the relevant laboratories. Summary Tables have been given in the earlier Milestone 6 Report and are further summarised in the SEAFMD presentations given in 2008 and 2010 and are also included as Attachments 2 and 3 in this Milestone resubmission. 2. Efficacy testing of vaccines o Evidence of efficacy testing of vaccine coverage was mentioned but not attached to the earlier Milestone 8 Report submission. However, substantiation is given in this Milestone resubmission, attached supporting SEAFMD presentations and were also detailed in the earlier Milestone 6 report. 3. Veterinarian and farmer recommendations for vaccination o Vaccine recommendations are currently being made by DAH personnel. This includes the inappropriate use of certain vaccine serotypes in specific regions and also the stamp-out policy in relation to incursions of new serotypes of FMD. o Recommendations in relation to improved vaccination protocols and the selection of the most appropriate vaccine for use in the field in specific regions of Vietnam have required the laboratories to maintain constant contact and feedback with both field veterinarians and farmers. This is a reiterative process with vaccine recommendations based on the results ongoing rounds of sero-surveillance and additional laboratory characterisation of field isolates. 4. Comments in relation to implementation of the project o The success achieved by RAHO-6 clearly attests to the utility of the approach adopted. In particular, close integration and communication of laboratory and field-based DAH personnel at RAHO-6 has led to the effective diagnosis, surveillance and control of FMD in southern Vietnam. o However, we acknowledge that epidemiological and field support at other locations were lacking and further compounded by recent AI and PRRSV outbreaks which unfortunately has led to a dilution of effort on FMD on the part of many regional laboratories and provincial DAH personnel. o Nevertheless, the approach adopted has proven its utility and should be applied in future efforts to control FMD on a national level in Vietnam. 8 5. Conclusions This project has successfully achieved Milestone 8 deliverables via the establishment of quality assured FMD diagnostic capacity within the network of veterinary laboratories in Vietnam. In this respect it should be noted that both the HCMC [RAHO-6] and Hanoi [NCVD] laboratories have attained FMD Reference Laboratory status and continue to provide FMD diagnostic support, training and FMD vaccination recommendations to other regional laboratories within the wider animal health network in Vietnam. In addition, in relation to sustainability, this project has also successfully established all the core competencies required within a wider animal health network for the on-going achievement of Milestone 8 deliverables at a regional level. However, it comes as no surprise that central to the effective control of FMD, and the achievement of Milestone 8 deliverables at both a regional and on a national level, is the closer integration, communication and collaboration of laboratory and field personnel. Such effective Reference Laboratory engagement with DAH and field veterinarians was exemplified by the dramatic improvement in sample and data collection at RAHO-6 during the course of this project. This resulted in more effective diagnosis, surveillance and control as a consequence of the serotyping and genotyping of field isolates which has greatly facilitated the evidence-based selection of the most appropriate vaccine formulation for use in specific regions in Vietnam. Although Milestone deliverables have been achieved by RAHO-6 on a regional basis in Vietnam it is nevertheless acknowledged that the other FMD Reference Laboratory (NCVD) has no epidemiology staff and this inherently results in lower quality field data. In addi