Veterinary public health research in SEA:
lessons for managing health risks in smallholder
pig systems
International symposium on Managing Risks in Emerging Pork Markets
Fred Unger
23rd - 25th of April 2012, Melia Hanoi Hotel

Content
1. Veterinary public health research in SEA
• Selected regional research
(focus on research under the VPHCAP, CMU Thailand)
– Examples by country and hazard
• ILRI pig Vietnam
2. Lessons for managing health risks in
smallholder pig systems

VPHCAP
Place: Vet Faculty of the
Chiang Mai University
VPHCAP: Veterinary Public Health Centre for Asia Pacific
Founded: October 2003
Objectives To create the regional information center in
food safety of food from animal origin the
countries in Asia Pacific.
Key activity: Joint Master of Science in Veterinary Pubic Health

Regional VPH Research (VPHCAP)
2003 - 2011
Countries: Thailand, Vietnam, Lao, Cambodia, Indonesia, Bhutan,
Nepal and China
Pig or pig products related topics:
• Microbiological quality, Salmonella spp. /E. coli contamination
• Antimicrobial resistant's and residuals
• Classical zoonoses: Taenia / Cysticercosis / Trichinellosis
Poultry or poultry products related topics:
• Microbiological quality, Salmonella/E. coli/Campylobacter
• HPAI
Ruminants/dog:
• Brucellosis, E. granulosis
Sea food related topics:
• Shrimps: Microbiological quality and contamination

Regional VPH Research
Pig and pig products - Vietnam
Studies on antimicrobial residuals or resistances
Analysis of Tetracycline Residues in Marketed Pork in Hanoi,
Vietnam
• Cross-sectional study
• 290 raw muscle samples (suburb and urban districts of Hanoi)
• Agar inhibition test and HPLC (High Performance Liquid Chromatography)
• 5.5 % (16/290) positive
• Factor region (origin of meat):
Odds Ratio 4.03 suburb versus urban district
MsC thesis: Duong Vat Nhiem

Regional VPH Research
Pig and pig products - Vietnam
Studies on antimicrobial residuals or resistances
A study on antimicrobial resistant of E. coli isolated from
Retail Fresh pork in Hanoi, Vietnam
• 403 pork samples from 141 meat retailers (out of 14 districts)
• 93.1% of E. coli isolates with observed resistance to at least one of
the 12 tested antimicrobials
• Tetracycline, OTC (>70%), followed by Sulphonamides. TMP
• Multi-resistances 89.6% (for up 11 antimicrobials)
• Risk factor – origin of meat (more likely to be observed in meat
from neighboring provinces then from Hanoi)
• Excessive drug abuse of pig farmers (suggested to be further
investigated)
MsC Thesis: Mr Chu Van Tuat

Regional VPH research
Pig and pig products Vietnam
Studies on microbial contamination
Microbial contamination of fresh minced pork from the
Retail market in Hanoi
• Fresh minced pork samples butcher shops and retail markets
• Salmonella and E. coli count
• 36.6% positive for Salmonella spp.
• OR (Odds ratio) 6.2 more likely to detect Salmonella in spring time
versus winter time (seasonal)(same applies for E. coli counts)
• Poor hygiene during fresh pork preparation
• Need of cool chain emphasized
MsC thesis: Ms. Pham Thi Thu Hien

Regional VPH Research
Pig and pig products Vietnam
Studies on microbial contamination
Prevalence of Salmonella in Pig Carcasses at a Slaughterhouse
In Hanoi, Vietnam
• 356 pig lymph nodes and carcass swaps
• Prevalence for Salmonella spp 56.5% (carcass swaps) and 34.8%
lymph node cuts
• Differences by farm type (lymph node cuts)
Backyard (43.2%) versus intensified farming systems (27.8 %)
MsC thesis: Nguyen Phu Thai

Regional VPH Research
Pig and pig products Lao
Microbiological Quality of Pig Carcass at Dorn Du Slaughterhouse in
Vientiane Municipality Lao PDR (MsC thesis: Mr. P. Inthavong)
• 46.8% – 66.1% Salmonella positive (meat swaps)
and 53.2 (lymph node)
Risk Assessment of Human Tape Worm Infection caused by Porcine
Cysticercosis in the Northern part of Lao (MsC thesis: V. Tammajedi)
• Free range farms significant higher than in enclosed farms
• Ante mortem (8%)(Se: 15% - 70%); post mortem 0%
• Human: records from 6 provinces (2004-2008: 199 annual average)
+ a few human cases of neurocysticercosis (NCC)

Regional VPH Research
Studies on Cysticercosis and Trichinellosis
Cambodia
Prevalence of Porcine Cysticercosis and Trichinellosis
in Slaughter Pigs of Cambodia (Msc thesis: Than Sovira)
• 4 slaughterhouses in Phnom Penh (432 pigs)
• 11% positive for cysticercosis (meat inspection) & 1.1% sero-
positive for trichinellosis
• Human hospital case review: no records, lack of knowledge
and diagnostic facilities

Regional VPH Research
Pig and pig products Nepal
Prevalence of Salmonella in retail meat shops in Kathmandu, Nepal
(MsC thesis: M. Upadhyaya)
 492 environmental swaps, 82 meat retail shops
 Salmonella contamination: chopping boards (36%), knifes (33%), tables (25%)
 Evening versus morning OR 1.9
 Risk factors: multiple persons vs. single persons involved, open vs. closed
shop, number of knives used, different meat types but single knife
Prevalence of porcine cysticercosis and trichinellosis in slaughter
pigs in Kathmandu, Nepal (MsC thesis: B. S. Sapkota)
 Cysticercosis (0.99%) only in outdoor &Trichinellosis (1%) all indoor pigs
 Human: NCC few cases (2000-2004, from 6 hospitals)

Regional VPH Research
Pig and pig products - Thailand
Source of salmonella in fattening pigs (Wunnakhum at al. 2011)
• Floor (40%), sewage (20%), water (20%), feed (negative)
• No difference between standard versus non-standard farms
Prevalence of Salmonella in breeder saws in Chiang Mai
(MsC thesis: R Ngasaman)
• Open house versus closed house system no significant difference (pigs)
• Environmental samples: higher prevalence's in open systems
Salmonella Prevalence's in pre-slaughter pigs in Chiang Mai, Thailand
(Msc thesis: Samart Dorn In)
• 95% Salmonella in floor swaps or waste water
• Fecal samples; 62% (22 pig farms)

Regional VPH Research
Pig and pig products - Thailand
Salmonella in Pork Products in Chiang Mai, Thailand
(MsC thesis: A. Sanguankiat)
• 173 meat cuts (SH), 173 transported pork, 200 retail pork
• 55% (SH meat cuts), 70% (transported pork) & 70% retail (bone products)
Microbiological quality along a selected product line of Thai
Northern Sausage (MsC thesis; Wiratsudakul)
• Some Salmonella spp, S. aureus, C. perfringensfound in integriends
• But not in final product (grilled with 100 C for 20 min and stored in fridge
for 7 days)

Regional VPH Research
Pig and pig products - Thailand
Prevalence study of Antibiotic Resistance in Swine Tissues in Chiang
Mai by using microbiological Assays(W. Chantong et al,2012, CMU)
• 15 % of antimicrobial resistance
Identification of Antimicrobial susceptibility of S. suisisolates from pig
tonsil swaps(C. Pansumdang et al,2012, CMU)
• High resistance to certain antimicrobial drugs (81-100%)

Regional VPH Research
Pig and pig products - Thailand
Consumer selection of pork and viscera in Chiang Mai and Lamphun
(P. Muenanan et al, 2012, CMU)
• Consumers choose pork based on freshness and cleanliness but no
strong interest in quality assurance certification
• Majority of consumers believe that pork is cleaner in supermarkets
than in fresh markets
• But tendency to prefer fresh markets as meet believed to be more
fresh (e.g. lower preference for frozen/chilled meat offered in
supermarkets)

Regional VPH Research (VPHCAP)
2012-2013
• Microbiological contamination (pig, chicken, sea food)
(e.g. Vietnam, bacteriological contamination along pig market
chain)
• Microbiological and other residuals
(e.g. Vietnam, antimicrobial residuals along pig market chain)
• BTB
• Brucellosis
• Camphylobacter

ILRI Pig Vietnam
Improving competitiveness of pig producers
in an adjusting Vietnam market
• Emerging concerns on food safety
• Consumer response to pig diseases
• Competiveness of HH pig producers
• Risk assessment (qualitative)
L. A. Lapar and project team

Pig Vietnam - Hazard Assessment
100
90 Supermarket
Wet market
80 s Village market
% UNACCEPTABLE
70
60 s
50
40
ns
v
30
ns
20
10
ns
0
Total bacteria Enterobac Staph Listeria Residues

2. Lessons for managing health risks in
smallholder pig systems
 Available research varies by country
 Research on Veterinary Public Health in SEA (and
Asia) more frequently related to studies on
microbiological contamination
 Includes collection of base line date for certain
production systems/processes
 Often focusing on the slaughter process alone
 Prior to slaughter studies less well researched

2. Lessons for managing health risks in
smallholder pig systems
 Hazards have been well documented in several studies
(in particular on slaughter/processing level)
 How observed hazards are related to the actual risk less
documented
 Risk assessment tools are rarely applied (in particular
quantitative tools) (few studies for Vietnam and Thailand)
 Farm – Fork approach, if applied than more likely for
large scale/industrial sector

2. Lessons for managing health risks in
smallholder pig systems
 Available research and control efforts focuses on
the medium/large scale sector
 Small scale production sector less researched
 small scale pig vs. studies on large scale premises
(e.g. CP Thailand, strong private sector &
Thailand/Vietnam/Indonesia/China: prioritization by policy
makers rather on large scale sector)

Final comments
• Hazards vs. Risk
• Farm to Fork
• Risk along value chains & role of actors
(informal sector)
• Capacity in risk and value chain analyses
• Demand for safe food & consumers perception
(includes informal sector)
• Behavior and incentive
• Integrated approaches (One Health)

Source of available literature:
• http://vphcap.vet.cmu.ac.th
• http://www.ncbi.nlm.nih.gov/pubmed/
• Promed mail
• FAO
• WHO: http;//who.int/salmsurv/links/en/