Texas study says soft ticks may complicate ASF response

A new Texas A&M study is sharpening one of the more complicated questions in African swine fever preparedness: what happens if the virus reaches pigs in a place where a native soft tick could help it linger. The study, published in Ecology and Evolution, mapped the likely distribution of Ornithodoros turicata and found suitable habitat across most of Texas, raising concern that the tick could complicate control efforts if African swine fever virus, or ASFV, is ever introduced into domestic or feral swine in the state. (onlinelibrary.wiley.com)

The backdrop is a U.S. swine industry that has spent years preparing for ASF without ever detecting the disease domestically. ASFV remains absent from the United States, but APHIS continues to treat it as a high-consequence foreign animal disease, and WOAH reports that the virus remains active across multiple regions globally, including the Caribbean. That geography matters for Texas, where cross-border livestock movement, feral swine populations, and wildlife interfaces already make preparedness more complex than a simple farm-to-farm biosecurity problem. (aphis.usda.gov)

The Texas A&M team used literature review, field collections, and ecological niche modeling to estimate where O. turicata is most likely to occur. According to the paper, ticks were collected in 15 of 16 surveyed Texas counties, and the resulting model suggested that the majority of Texas, excluding the easternmost quarter, is highly suitable habitat. The study also identified central Texas and Florida as areas of high host-species richness that may deserve targeted surveillance, and it noted O. turicata in burrows occupied by feral common warthogs in South Texas, a notable finding because warthogs help sustain ASFV in a sylvatic cycle in Africa. (onlinelibrary.wiley.com)

That doesn’t mean Texas is facing an imminent tick-driven ASF outbreak. The more immediate point is persistence. In Texas A&M’s accompanying university coverage, Meriam Saleh, PhD, said the risk deserves attention because the consequences of introduction would be severe, while dvm360 reported her explanation that these ticks feed at night, can survive for years between blood meals, and may live a decade or longer. Saleh and co-lead Dee Ellis, DVM, MS, framed the tick less as a driver of large-scale spread than as a possible long-term reservoir that could reintroduce virus after infected pigs were depopulated and new animals moved back in. (stories.tamu.edu)

That framing is important because it fits, and also challenges, existing federal planning. APHIS says ASF can be transmitted by Ornithodoros soft ticks, but its 2026 response plan also notes that the specific soft tick species historically tied to ASF persistence in Africa and the Iberian Peninsula are not present in the United States. The Texas study doesn’t overturn that; instead, it argues that a native U.S. species with laboratory evidence of vector competence and broad Texas habitat may still deserve a more prominent place in surveillance and response discussions. In other words, the operational question for veterinarians may not be whether Texas has the “classic” ASF tick ecology, but whether it has enough ecological overlap to make eradication harder if the virus arrives. (aphis.usda.gov)

Why it matters: For swine veterinarians, diagnosticians, and state animal health teams, the study is a reminder that outbreak response planning may need to extend beyond infected premises and direct-contact tracing. If soft ticks can maintain ASFV locally, then repopulation timelines, environmental assessment, feral swine surveillance, and vector monitoring could become more relevant in parts of Texas than many preparedness plans currently assume. The work also supports more risk-based surveillance, since passive tick detection may miss a cryptic, nest-dwelling species that feeds briefly and off-host. That has implications not only for commercial production, but also for backyard swine and any setting where pet parent education, wildlife contact, and uneven biosecurity intersect. (dvm360.com)

What to watch: The next key data point is vector competence work in Texas-derived tick populations, which Texas A&M says is part of a Department of Homeland Security-funded research effort. If those studies show efficient acquisition and retransmission under realistic field conditions, they could influence how APHIS, Texas officials, and the swine industry define surveillance zones, repopulation safeguards, and wildlife-vector control priorities. (stories.tamu.edu)