Romanian ASFV study confirms genotype II, highlights tracing limits

A newly published Romanian study in Veterinary Sciences takes a closer look at two familiar African swine fever virus markers, p72 and the B602L central variable region, to characterize viruses circulating in domestic pigs and wild boar. The headline finding is straightforward: the Romanian isolates that yielded usable sequences remained firmly within ASFV genotype II at p72, underscoring how genetically conserved the country’s outbreak strain still appears on this standard marker. (mdpi.com)

That result fits the broader history of ASF in Romania and Europe. Romania previously reported genotype II in symptomatic pigs, consistent with the lineage that spread westward after the Georgia 2007 incursion and became established across much of Eastern and Central Europe. In the EU, ASF control has increasingly depended on regionalization, movement restrictions, wildlife management, and surveillance, with the European Commission maintaining country- and zone-specific measures under Implementing Regulation (EU) 2023/594 and subsequent amendments. (mdpi.com)

In the new paper, investigators worked from 54 ASFV-positive field samples collected from domestic pigs and wild boar. After PCR confirmation, Sanger sequencing, and sequence-quality filtering, they retained 33 consensus sequences for the p72 target and 32 for B602L. According to the MDPI article page, p72 sequencing showed a very high degree of nucleotide conservation, with all successfully sequenced isolates assigned to genotype II. That’s useful confirmation, but it also illustrates the known limitation of p72: it’s strong for genotype assignment, yet often too conserved to separate closely related genotype II outbreak strains on its own. (mdpi.com)

That’s where B602L comes in. The central variable region of B602L has long been used for intra-genotypic discrimination, because tandem-repeat variation can provide more epidemiologic resolution than p72 alone. Even so, published genotype II work from other countries has shown that p72 plus CVR may still fall short when investigators need to distinguish very closely related outbreak viruses, prompting many groups to add other loci or move to whole-genome approaches. In that sense, the Romanian study is both practically useful and a reminder of the ceiling on what these classic markers can deliver in a mature genotype II epidemic. (pubmed.ncbi.nlm.nih.gov)

Industry and regulatory context makes that nuance important. WOAH’s April 29, 2026 ASF situation report summarized data submitted in March 2026, and EFSA reported in May 2026 that ASF outbreaks rose across the EU in 2025 in both domestic pigs and wild boar, with Romania among the countries showing a clear winter peak in wild boar outbreaks. Separately, disease surveillance reporting in 2026 continued to list Romania among European countries with outbreaks in both domestic pigs and wild boar. Together, those signals suggest that molecular characterization remains relevant not because the genotype question is unsettled, but because field epidemiology still needs better tools to understand persistence, spillover, and local transmission dynamics. (woah.org)

Why it matters: For veterinary professionals, this is a surveillance story more than a breakthrough story. The study supports continued use of p72 and B602L as accessible, established tools for confirming genotype II circulation and comparing Romanian isolates across host populations. But it also points to the practical need for higher-resolution typing when officials are trying to connect outbreaks, evaluate whether domestic-pig cases reflect repeated wildlife introductions or farm-to-farm spread, and refine control measures in a country operating under ongoing EU ASF restrictions. The European Commission notes that ASF remains subject to special Union control measures and zoning, reflecting how much disease management still depends on precise epidemiologic intelligence. (food.ec.europa.eu)

For swine veterinarians and animal health authorities, the study’s value is in strengthening the evidence base for surveillance strategy. If Romania’s circulating viruses remain highly uniform at p72, then incremental gains are more likely to come from combining classical markers with additional genomic targets, stronger integration of wildlife and domestic surveillance, and broader use of sequencing approaches that can resolve near-identical genotype II viruses. That’s especially relevant in a disease that remains devastating for pigs and wild boar, does not affect humans, and still lacks a widely deployed control solution robust enough to replace biosecurity, rapid detection, and movement management in Europe. (food.ec.europa.eu)

What to watch: The next step is whether Romanian and regional investigators expand from marker-based characterization into multilocus or whole-genome surveillance, and whether those data start to translate into more actionable outbreak tracing under Europe’s still-evolving ASF control framework. (mdpi.com)