Molecular surveillance of African swine fever virus in raw pork and blood samples from wet markets and abattoirs in Tuguegarao City, Cagayan
Paper Details
Molecular surveillance of African swine fever virus in raw pork and blood samples from wet markets and abattoirs in Tuguegarao City, Cagayan
Abstract
African Swine Fever (ASF) is a highly lethal transboundary disease that endangers swine production and food security. This study conducted active molecular surveillance to detect ASF virus (ASFV) in raw pork and whole-blood samples collected from local government–sanctioned wet markets in Tuguegarao City. From August to October 2025, a total of 180 specimens (30 meat and 30 whole-blood samples per month) were collected, pooled by stall owner and market, and transported cold for laboratory processing. Nucleic acids were extracted and screened using real-time PCR assays targeting the VP72 (B646L) gene, with appropriate extraction, weak and strong positive, and no-template controls to ensure run validity. Results showed that all specimens produced undetermined cycle threshold (Ct) values and lacked characteristic amplification curves, yielding 0/180 PCR positives. Quality control amplification of positive controls and flat negative controls confirmed assay performance. Exact Clopper–Pearson binomial analysis generated a two-sided 95% confidence interval of 0.00 to 0.02029 for true prevalence, placing an upper bound of 2.03%. These findings indicate ASFV was not detected from any of the samples analyzed, while acknowledging potential limitations such as pooling, sample size, viral loads below the assay limit of detection, or nucleic acid degradation. The study recommends sustained surveillance with increased sample numbers and duration, biosecurity assessments at market and farm levels, and data linkage with live-swine surveillance to strengthen early detection and protect local pork value chains.
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Hannah Lee R. Guirren*, Benjamin Abella, Aira D. Cuarteros, 2026. Molecular surveillance of African swine fever virus in raw pork and blood samples from wet markets and abattoirs in Tuguegarao City, Cagayan. Int. J. Biosci., 28(5), 66-75.
Copyright © 2026 by the Authors. This article is an open access article and distributed under the terms and conditions of the Creative Commons Attribution 4.0 (CC BY 4.0) license.