FMD risk assessment in endemic settings using value chain. Julio Pinto Animal Health Officer EMPRES/GLEWS

Transcription

1 FMD risk assessment in endemic settings using value chain Julio Pinto Animal Health Officer EMPRES/GLEWS

2 FMD surveillance and control activities such as vaccination are regularly focused on the density and distribution of livestock population without taking into account the level of risk of different ecosystems, production systems and chains.

3 Value chain A value chain describes the full range of activities which are required to bring a product or service from conception, through the different phases of production (involving a combination of physical transformation and the input of various producer services), delivery to final consumer, and final disposal after use

4 Collaborative project FAO/VEERU The first phase started with an initial desk based data collection and ended with one workshop in each of three endemic FMD countries (Venezuela, Ecuador and Vietnam). Based on the data gathered, the second phase concentrated on development of detailed value chains for different production systems and products in each country. The third and last phase is the identification of risk hotspots and their assessment.

5 Cattle Subsistence Production Systems Large parts of south-central Andean and Amazonas regions. Farms have few cattle per ha. and also keep sheep, goats and pigs. Herds and farm sizes are small and milk production ranges from low to medium. CATTLE SUBSISTANCE PRODUCTION SYSTEMS IN ECUADOR Meat production (Azuay, Cotopaxi, Bolivar, Imbaburam Pichincha, Pastazam Tungurahua). Cattle fattened & marketed. Market Mixed production Low productivity: cattle used for meat & milk production, traction & cultivation. Milk production About 5l/cow/day. Abattoir Milk processing plant Butchers Consumers

6 INFORMAL IMPORT AND EXPORT OF ANIMALS (COLOMBIA) SPECIALIZED PRODUCTION Holstein-Friesian; mainly in Merida and Portuguesa 10% RAW MILK DUAL PURPOSE PRODUCTION Zebu and Crossbreeds; mainly in Zulia, South of Lake Maracaibo 90% PROCESSING PLANT... WHEY Fed to PIGS in backyard production systems 77%: Milk collection 23%: Cheese production on farm Replacement animals, Discards, Male Calves TRADER CONSUMER Wholesaler Retailer Dairy value chain in Venezuela Milk from dual purpose beef production

7 Production Local slaughters Collectors, Small slaughterhouse?where are the slaughterers? Local assemblers Local agents Urban traders Internal organ collector Meat processor Value chain for pork in cities and small urban areas in North Viet Nam Restaurants Urban retailers Urban consumers

8 Approach Risk pathways Risk issues Risk assessment Value chain questions Value chain analysis Value Chains Critical Risk Points/times in value chain

9 Risk assessment methodology To make qualitative assessments of FMD risk: introduction into transmission within; and transmission out of, North Viet Nam, Ecuador and Venezuela.

10 Risk pathway RELEASE EXPOSURE AND FIRST INFECTION consequence DISEASE SPREAD FMD virus is present in an outside country. FMD virus enters country Livestock in the country exposed to FMD virus. FMD virus infects first livestock in the country. FMD infection spreads among local livestock

11 Identification of risk control points Most risk for FMD spread in all three countries comes from: movements of live animals, contamination from poorly regulated slaughter facilities and spread by fomites carried by traders and transporters of live animals and to a lesser extent fomites carried by other farm service providers. Communal grazing and sharing of breeding males also contribute to risk of local spread. In the closing phase of this project it is needed to revisit the value chains in more detail to understand how these risks can be mitigated in a stakeholder-friendly way.

12 Preliminary conclusions in validation in three endemic FMD countries: follow up with FAO project in CAN region stakeholder based approach understanding value chains will help to understand the epidemiology of FMD in endemic settings understanding value chains will support risk assessment design of risk based-surveillance and targeting of risk reduction measures (animal health regulations, vaccination, FMD surveillance, biosecurity, etc..) compartmentalization

13 Acknowledgement Nick Taylor (VEERU) Tony Wilsmore (VEERU) Jonathan Rushton (FAO) Juan Lubroth (FAO)

14 FMD in endemic settings Giancarlo Ferrari Project Coordinator GTFS/INT/907/ITA Controlling Trans-boundary Animal Diseases in Central Asian countries AGAH/EMPRES FAO

15 Background GTFS/INT/907/ITA project Controlling Trans-boundary animal diseases in Central Asian countries started its activities in 2004; It is a Regional Project supported by the Italian Government with the following beneficiary countries: Afghanistan, Pakistan, Tajikistan, Turkmenistan and Uzbekistan

16 Background Phase 1 of the GTFS/INT/907/ITA was concluded on 31 December 2007; Main objective (in all countries but Pakistan): to demonstrate freedom from Rinderpest; As a result during the last OIE General Session (May 2008) Afghanistan, Tajikistan and Uzbekistan have been recognized officially free (Turkmenistan is still pending), while Pakistan was recognized free in 2007.

17 Background Project has been extended until 31 December 2009 and phase 2 will focus more on FMD and Peste des Petit Ruminants (PPR); A shift on the approach: demonstrating freedom from a given disease vs have a better understanding of diseases likely to be present

18 Background In Pakistan, which was a step ahead as per the Rinderpest pathway, the project has supported field activities in collaboration with the National Veterinary Institute, Technical University of Denmark, Lindholm (period April 2006-April 2007); Those field activities have been carried out in the largest Dairy Colony in the world (Landhi Colony, Karachi) form April 2006 to April 2007.

19 FMD in endemic settings Dairy farm in Landhi (from Soren Alexandersen) The dairy colony production system has some peculiar characteristics with the most importants being: (i) a high turn-over of the animals (on average 10 to 12 per cent of animals in dairy colonies are replaced monthly) and (ii) a huge animal density.

20 FMD in endemic settings This system is dominated by the buffaloes because of the higher butterfat that is preferred by the customers; During the study period a serological investigation was carried out and 180 serum samples collected between October 2006 and April 2007 from slaughtered animals that had spent at least one lactation period into the Landhi Colony;

21 FMD in endemic settings Out of 180 samples collected 176 (98%) had detectable levels of NSP antibodies (Klein, J. et al, Virology Journal 2008, 5: 53). This finding was consistent with animals, sampled at any given point in time (slaughter) that had the common experience of having spent at least one lactation period ( days) in Landhi

22 FMD in endemic settings Presently no data are available on the level of NSP antibodies that may be present on the population entering for the first time the colony. Undoubtedly the level of exposure to FMDV seems to be relevant and it is thus assumed that transiting into the colony would increase the risk of exposure to FMD virus to a certain extent which should be reflected in the different level of antibodies between pre and post-exposure.

23 FMD in endemic settings The study carried out in the Dairy Colony provides a good indication of how the level of exposure to FMD virus may be strictly linked with a specific productive system. It is in fact suggested that this peculiar system could be targeted for a vaccination program which in turn should contribute to reducing the overall load of the FMD virus.

24 FMD in endemic settings Dairy Colonies are rather peculiar to Pakistan and no such productive systems are known to be present in Afghanistan, Tajikistan, Turkmenistan and Uzbekistan. [Of note, the Dairy Colonies were also considered as a key eco-system for rinderpest virus to persist in Pakistan.];

25 FMD in endemic settings While for Pakistan, the Dairy Colony may be considered an important hot spot for FMD virus, other production systems with equivalent or significant level of risk may be identified and targeted for control programs in order to progressively reduce the overall load of FMD virus; Live animal market (from Peter Roeder)

26 FMD in endemic settings In this regard, and in an attempt to quantify how the overall risk of becoming infected with FMD virus may be differently distributed, the following categories have been identified in the participating countries of GTFS/INT/907/ITA: (i) households animals; (ii) commercial sector - dairy; (iii) commercial sector - beef; (iv) genetic centers (usually government farms); (v) dairy colonies (only in Pakistan); (vi) animals seasonally moved to pastures; (vii) animals at slaughterhouses.

27 FMD in endemic settings The level of exposure to FMD virus will be measured through the detection of NSP antibodies and the target species for the survey will be cattle and buffaloes, which are considered equivalently susceptible (to infection). The sample design and criteria adopted to conduct the study is a combination of what could be practically achieved while providing some statistical robustness.

28 FMD in endemic settings The general criteria established for estimating the sample size aimed at: (i) maintaining the overall standard error of the estimated proportions for each category at an acceptable level (maximum tolerable error 11% at 95% confidence level); (ii) being able to detect (at 95% confidence level) the presence of at least one NSP antibodies positive animal if the proportion (in each age category) of positive is equal or more than 20% (with no adjustment for test sensitivity and specificity); (iii) verifying that the minimum detectable prevalence risk ratio between two independent proportions (with a type I error of 0.05 and a type II error of 0.1) would not exceed 3.2

29 FMD in endemic settings Table 1: Minimum sample size required in different categories per each country Category Household (epiunit = village) Dairy Beef Genetic centers Transhumants/ Pastoralists Slaughtered Colonies N. units to be sampled n.a. n.a. n.a. N. Individual Samples (two rounds of 150 each) (two rounds of 150 each) Max SE 3.2% 11% 11% 11% 8.2% 5.8% 8.2% (95%) * Range of Min. detectable PRR

30 Team building in Uzbekistan THANKS for your attention