KUALA LUMPUR, Jan 23 — Prominent virologist Prof Dr Lam Sai Kit has lent support to the centralised pig farm project in Bukit Tagar, Hulu Selangor, saying it will help prevent animal disease outbreaks.
The expert in medical virology and public health from Universiti Malaya, who is also a senior fellow at the Academy of Sciences Malaysia, said Malaysia has been encouraging a shift towards modern pig farming (MPF) and pig farming areas (PFAs) that require closed-house systems, zero-discharge waste treatment, centralised veterinary oversight, and zoning away from residential and wildlife areas.
However, he noted that transition is ongoing and uneven, with some states like Penang and Selangor making more progress than others.
“Modern and centralised pig farming enhances public health protection by enabling systematic disease control, environmental management, and traceability,” Dr Lam told CodeBlue in an email interview.
“Key benefits include:
- Controlled biosecurity: Centralised farms implement perimeter fencing, disinfection zones, and controlled entry points to prevent disease introduction.
- Standardised waste treatment: Centralised systems allow for engineered wastewater treatment and odour control, reducing contamination of nearby water sources and communities.
- Veterinary oversight: Regular health monitoring, vaccination, and disease surveillance are easier to implement and enforce in a centralised setting.
- Rapid response capacity: In the event of an outbreak, authorities can swiftly isolate and manage affected zones without the logistical challenges of dispersed sites.”
Dr Lam led a 15-member team from the Faculty of Medicine, Universiti Malaya, that discovered the Nipah virus, then a novel virus, during a 1998-1999 outbreak in Malaysia that devastated the pig farming industry with over a million pigs culled. A total of 109 deaths were reported from human cases of viral encephalitis during the outbreak.
Nipah is a zoonotic virus transmitted from animals to humans and can also be transmitted through contaminated food or directly between people. Fruit bats are natural hosts for Nipah virus; the virus is also highly contagious in pigs.
The Nipah Virus Encephalitis Investigation Team received a Merdeka Award in 2008. Dr Lam, a prominent scientist who has been at the forefront of infectious viral disease research for more than four decades, was conferred a Merdeka Award in 2013 for outstanding scholastic and academic achievement.
Bat-Proofed Modern Farm Reduces Risk Of Nipah Virus
Dr Lam explained that traditional pig farming in Malaysia typically involves small-scale, open-air systems with small holder farms with 50 to 500 pigs, and are often family-run. These small farms are usually located near rural villages or forest edges.
“The methods used are low-cost, but may pose environmental and public health risks,” he said.
“Open systems increase contact with bats, rodents and other wildlife, and environmental pollution by untreated effluent contaminating rivers and groundwater. Poor waste control attracts flies and rodents, affecting nearby communities.”
The virologist highlighted the dispersed and poorly regulated nature of pig farms in the 1990s as a factor in the spread of Nipah virus during the Malaysian outbreak then.
“Farms were often located near fruit orchards and bat habitats, facilitating bat-to-pig transmission. The lack of coordinated surveillance and movement control allowed the virus to spread across districts and states,” said Dr Lam.
“The outbreak highlighted the dangers of uncoordinated animal movement, poor biosecurity, and proximity to wildlife reservoirs.”
He stressed that pig farming in general doesn’t pose Nipah risk. “Certainly, modern farms which are typically enclosed, bat-proofed, and monitored will reduce this risk.”
“Bigger farms do not mean bigger outbreaks since centralised farms are easier to regulate and isolate. The 1999 outbreak in Malaysia spread through small and medium farms with poor oversight.”
According to Dr Lam, the Bukit Tagar model incorporates integrated biosecurity infrastructure that is difficult to implement across scattered farms.
“There will be strict control measures, dedicated isolation zones for new and sick animals, centralised labs for routine screening and real-time data sharing and better reporting and traceability of livestock,” he said.
“These measures reduce the risk of zoonotic spillover by limiting contact with wildlife, ensuring early detection, and enabling swift containment.”
Centralised Pig Farming Reduces Odour Emissions
Dr Lam also corrected misconceptions that Nipah is a pig disease, clarifying that Nipah is a bat-borne virus.
“Pigs were amplifiers in the 1999 outbreak, but the root cause was human-wildlife-livestock interface mismanagement,” said the virologist. “It must be remembered that the ongoing outbreak of Nipah in Bangladesh has nothing to do with pigs, and there has been no re-introduction of Nipah into Malaysia.”
Opponents of the Bukit Tagar project have engaged in fearmongering online by citing the 1999 Nipah virus outbreak, omitting to mention how centralised or modern pig farming boosts disease prevention and control.
According to Dr Lam, key non-zoonotic risks from pig farming include wastewater contamination, water safety, odour, and air quality and vector control (flies and rodents).
Centralisation of farms, he said, will reduce runoff into rivers and groundwater, reduce odour emissions and improve air quality, improve vector control by implementing integrated pest management, and ensure buffer zones and water monitoring, thus protecting nearby communities.
“In short, centralisation makes these risks more manageable, provided the infrastructure is well-designed and regulations are enforced.”
Centralised Pig Farming Reduces ASF Risk
Last year saw two African swine fever (ASF) outbreaks in Selangor and Penang. Some 76,000 pigs were culled in 57 farms around Kuala Langat and Sepang in Selangor. ASF, now considered endemic in Malaysia, is a non-zoonotic virus that doesn’t infect humans.
Dr Lam said the Selangor and Penang outbreaks showed that ASF spreads rapidly when farms are densely packed, but poorly coordinated.
“In contrast, centralised models like Bukit Tagar offer:
- Controlled access: Single entry points with disinfection protocols reduce the chance of virus introduction via vehicles, feed, or personnel.
- Zoning and spacing: Proper separation between units and farms limits direct and indirect contact, unlike traditional farms that may be just 500m to 1,000m apart.
- Standardised protocols: Centralised farms can enforce uniform biosecurity, carcass disposal, and movement restrictions.
- Integrated surveillance: Centralised data systems allow for real-time health monitoring and faster detection of abnormal mortality.”
Dr Lam recommended the following measures for centralised farms to prevent and control ASF:
- Strict movement control: Prevents spread via contaminated vehicles, feed, or personnel.
- All-in/all-out systems: Reduces mixing of age groups and disease transmission.
- Routine surveillance: Enables early detection of fever, mortality spikes, or clinical signs.
- Rapid culling and disposal: Infected pigs must be culled and buried or incinerated safely.
- Disinfection and downtime: Thorough cleaning and rest periods between production cycles.
- Training and audits: Ensures staff compliance with protocols and early reporting.
The Department of Veterinary Services’ (DVS) “find one, cull all” approach, where detection of a single ASF case triggers an immediate alert to all farms in the network, is feasible and vital in a centralised model, he said.
“Besides Nipah, a centralised pig farming model can significantly reduce the risk of ASF by enabling stricter biosecurity, faster outbreak response, and coordinated surveillance.”
Agriculture and Food Security Minister Mohamad Sabu told Parliament last August that ASF outbreaks reduced Malaysia’s self-sufficiency ratio (SSR) for pork to 69.6 per cent in 2023 from 93.4 per cent in 2021.
He had also touted MPF and PFA to ensure controlled and sustainable pig farming.
Selangor state executive councillor for infrastructure and agriculture Izham Hashim recently said traditional pig farms in Tanjong Sepat, Kuala Langat, would be relocated to the 500-acre centralised farm in Bukit Tagar as soon as possible. The state government has reportedly identified 69 licensed pig farm operators.
‘Thousands Of Lives And Livelihoods Dependent On Pig Farming Industry’
Dr Lam noted that high cost is a barrier for pig farmers, especially small and medium farmers, to shift to centralised pig farming, as upgrades can cost millions of ringgit per farm, depending on the scale and location.
“For example, wastewater treatment alone is a major cost driver, and many farmers struggle to afford the transition. Many smallholders lack capital or access to financing. Some have exited the industry rather than upgrade,” he said.
“Without sustained financial and policy support, centralised pig farming may remain limited to large-scale operators. Public-private partnerships, low-interest loans, and cooperative models could help smaller farmers transition. Phased implementation with clear timelines and technical guidance can ease the burden and build trust.”
The virologist stressed that centralisation is a necessary path for sustainable, biosecure pig farming in Malaysia.
“Above all, any proposal to set up centralised pig farming projects in the country should involve discussion with stakeholders as thousands of lives and livelihoods are dependent on this industry.”
