The Provincial Veterinary Office (PVO) of Negros Oriental—led by Provincial Veterinarian Dr. Melody Vilan—has reported new cases of African Swine Fever (ASF) across three Local Government Units (LGUs): Siaton, Amlan, and Tanjay City.
In response to positive laboratory confirmations from the Bureau of Animal Industry (BAI), state agricultural and veterinary teams initiated targeted depopulation (culling) of infected and co-housed pigs, launched expanded surveillance testing, and enforced strict quarantine controls to safeguard the broader Visayas swine corridor.

LGU Breakdown: Confirmed Cases & Field Operations
Laboratory testing of blood samples submitted to the Bureau of Animal Industry confirmed viral activity across multiple agricultural barangays.
Affected LGU |
Confirmed Positive Barangays |
Laboratory Positivity Rate |
Containment Actions Taken |
Siaton |
Maloh, Tayak |
75.0% (6 positive / 8 samples) |
Hogs succumbed prior to testing; expanded surveillance & disinfection active. |
Amlan |
Bio-os, Silab, Jantianon, Jugno |
40.0% (20 positive / 50 samples) |
52 hogs culled (including exposed pen-mates); ongoing blood sampling. |
Tanjay City |
San Miguel, Sta. Cruz Nuevo, San Isidro, Azagra, Brgy 3, Novallas, Brgy 4, 6, 8, Sta. Cruz Viejo |
88.8% (24 positive / 27 samples) |
40 hogs culled; localized quarantine zones enforced across urban/rural barangays. |
Containment Protocol & Biosecurity Execution
To mitigate wider transmission across the island of Negros and adjacent maritime trade routes, the PVO and municipal authorities are executing a multi-tiered containment protocol aligning with national Bantay ASF sa Barangay (BABay ASF) guidelines:
[ FIELD CONTAINMENT & DISINFECTION PROTOCOL ]
1. Focal Depopulation ──► Humane culling of infected pigs & animals in direct contact.
2. Chemical Decon ──► Premises disinfection with broad-spectrum virucidal agents.
3. Perimeter Sampling ──► Multi-point blood sampling within 1km to 5km buffer zones.
4. Trace-Back Audit ──► Investigating swill-feeding, illegal transport, & farm visits.
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Targeted Depopulation & Disinfection: Animals in direct contact with confirmed cases are culled and buried following sanitary protocols. Farm units undergo mandatory cleaning using virucidal disinfectants to neutralize environmental viral persistence.
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Movement & Trade Bans: Municipalities with active red-zone barangays are under strict trade bans. Transporting live pigs, piglets, or raw pork out of Siaton, Amlan, and Tanjay City without negative laboratory clearing certificates and veterinary health permits is prohibited.
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Surveillance Ring Clearances: Concurrently, negative laboratory test results were confirmed in neighboring LGUs—including La Libertad (66 negative samples), Canlaon City (60 negative samples), Mabinay (30 negative samples), Dauin (14 negative samples), and Sta. Catalina—enabling these regions to maintain monitored green/yellow zone status.
Technical Epidemiology: Risk Drivers in Backyard Swine Systems
The resurgence highlights systemic vulnerabilities characteristic of smallholder and backyard swine production across Southeast Asia:
[ VECTORS OF ASF SPREAD IN BACKYARD FARMS ]
Fecal / Fluid Contact ──► High viral shedding in blood, saliva, & mucosal fluids.
Swill Feeding ──► Feeding untreated household or food service scraps.
Fomite Transmission ──► Unsterilized vehicles, livestock traders, & farm tools.
Lack of Physical Barriers ──► Free-roaming pigs & wild suid interactions.
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Swill-Feeding Risks: Ingestion of untreated, contaminated pork scraps remains a primary vector for inter-farm transmission.
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Fomite Mechanics: The African Swine Fever virus (ASFV) exhibits high environmental resilience, surviving on footwear, transport vehicles, and tools for extended periods without proper chemical decontamination.
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Trader-Mediated Transport: Unregulated movement of asymptomatic or early-stage infected pigs by informal livestock traders accelerates geographic dispersal before clinical symptoms appear.
Public Health Advisory & Industry Guidelines
[ VETERINARY & PRODUCER DIRECTIVES ]
Report Unexplained Deaths ──► Contact Municipal Agriculture / PVO immediately.
Halt Swill Feeding ──► Transition to commercial or thoroughly cooked feed.
Enforce Perimeter Access ──► Restrict visitors, vehicles, & shared farm equipment.
Verify Shipping Permits ──► Transport hogs ONLY with accredited BAI certificates.

