fmd risk assessment in endemic settings using value chain...collaborative project fao/veeru the...

FMD risk assessment in endemic settings using value chain

Julio Pinto

Animal Health Officer

EMPRES/GLEWS

�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.

�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’

Value chain

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.

CATTLE

SUBSISTANCE

PRODUCTION

SYSTEMS IN

ECUADOR

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.

Mixed production

Low productivity: cattle

used for meat & milk

production, traction &

cultivation.

Milk production

About 5l/cow/day.

Meat production

(Azuay, Cotopaxi,

Bolivar, Imbaburam

Pichincha, Pastazam

Tungurahua). Cattle

fattened & marketed.

Milk processing plant

Market

Abattoir

Butchers

Consumers

Wholesaler

Retailer

WHEYFed to PIGS in backyard

production systems

Milk from dual purpose beef production

TRADERTRADER

Replacement animals, Discards, Male Calves

.

.

.

PROCESSING PLANT

77%: Milk collection 23%: Cheese production on farm

CONSUMER

SPECIALIZED PRODUCTION

Holstein-Friesian; mainly in Merida and Portuguesa

10%

DUAL PURPOSE PRODUCTION

Zebu and Crossbreeds; mainly in Zulia, South of Lake Maracaibo

90%

INFORMAL IMPORT AND EXPORT OF ANIMALS (COLOMBIA)

RAW MILK

Dairy value chain in Venezuela

Production

Collectors,

Small

slaughterhouse

Urban consumers

Local assemblers

Urban retailers

Local agents

Local

slaughters

Internal organ

collector

Meat processor

Restaurants

Urban traders?where are the

slaughterers?

Value chain for pork in cities and small

urban areas in

North Viet Nam

• Risk issues

••••

• Value chain questions

••••

Ris

k p

ath

wa

ys

Valu

e C

hain

s

‘Critical Risk Points/times’ in value chain

Risk assessment

Value chain analysis

Approach

To make qualitative assessments of FMD risk:

� introduction into

� transmission within; and

� transmission out of, North Viet Nam, Ecuador and

Venezuela.

Risk assessment methodology

FMD virus

infects first

livestock in the

country.

Livestock in

the country

exposed to

FMD virus.

RELEASE EXPOSURE AND FIRST INFECTIONconsequence

DISEASE SPREAD

FMD virus

enters

country

FMD virus is

present in an

outside country.

FMD infection spreads

among local livestock

Risk pathway

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.

Identification of risk control points

� 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

Preliminary conclusions

Acknowledgement

� Nick Taylor (VEERU)

� Tony Wilsmore (VEERU)

� Jonathan Rushton (FAO)

� Juan Lubroth (FAO)

FMD in endemic settings

Giancarlo FerrariProject Coordinator GTFS/INT/907/ITA

“Controlling Trans-boundary Animal Diseases in Central Asian countries”

AGAH/EMPRESFAO

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

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.

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

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.


• 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.

Dairy farm in Landhi (from Soren Alexandersen)


• 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;


• 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 (230-300 days) in Landhi


• 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.


• 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.


• 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.];


• 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)


• 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.


• 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.


• 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

FMD in endemic settingsTable 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

60 5 5 5 n.a. n.a. n.a.

N. Individual

Samples

2880 240 240 240 300 (two rounds

of 150 each)

300 300 (two

rounds of

150 each)

Max SE

(95%)*3.2% 11% 11% 11% 8.2% 5.8% 8.2%

Range of

Min.

detectable

PRR

1.36

2.7

1.52

3.2

1.52

3.2

1.52

3.2

1.38

2.5

1.22

1.7

1.38

2.5

Team building in Uzbekistan

THANKS for your attention

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