Illustrated Texas landscape with a wild pig beside a creek, cattle in a pasture and an oak tree.

A Texas field guide

Health & environmental risk

Wild pigs share land and water with wildlife, livestock and people. Explore what the research measures — and what it cannot tell us.

A sourced educational reference, not a personal risk forecast, live sighting feed or service map.

01 / The shared landscape

Health begins with understanding the evidence

Wild pigs can carry pathogens that matter to animals and people. A positive antibody test, a detected organism and a demonstrated transmission event answer different questions.

Three connected illustrations: a wild pig, laboratory equipment and samples, and a person with a dog overlooking cattle.
Illustrative artwork connecting wildlife, research, people and animals — not a record of sampling or a specific field visit.

Antibody exposure

Has the immune system responded?

Serology can indicate prior exposure. It does not, by itself, establish current infection, infectiousness or a person’s chance of becoming ill.

Pathogen detection

What was found in the sample?

PCR detects genetic material in a particular specimen. Kidney DNA does not itself demonstrate live organisms being shed in urine.

Transmission evidence

Was spread between hosts established?

Demonstrating a transmission route needs additional evidence. Overlap on a map is not proof that hogs caused human cases.

These are different evidence types, not a universal step-by-step progression. Sample design, test performance, place and year all affect interpretation.

Texas studies & agency context

Texas • published 2009 • antibodies

Brucellosis & pseudorabies

Wyckoff and colleagues reported 11% brucellosis and 30% pseudorabies antibody prevalence in their Texas feral-swine sample.

Keep in mind: Historical sample results are not a current statewide census, active-infection count or personal risk estimate.

Methods, limits & sources

The study is published in Journal of Wildlife Diseases 45(2):422–429. TAHC also provides approximate agency figures of 10% for brucellosis and 20% for pseudorabies; those figures and this historical serosurvey are not interchangeable measurements. Consult the paper for its sampling design and diagnostic methods.

Texas • 2005–2006 samples • antibodies

Influenza exposure

Hall and colleagues reported 14.4% influenza antibody prevalence in sampled Texas feral swine.

Keep in mind: Antibodies indicate exposure, not that 14.4% were actively infectious. Results varied geographically.

Methods, limits & sources

The 2008 paper compared samples from six U.S. states: Texas, California, Mississippi, Oklahoma, Florida and Missouri. Texas had the highest sample percentage; California reported 5%, Mississippi 1%, and no antibodies were detected in the other three sampled states. A non-detection is not proof of absence.

Texas • 2018–2023 samples • serology

Q fever: exposure, not a traced route

McMillan and colleagues reported Texas seropositivity as high as 6.03% for Coxiella burnetii, the bacterium that causes Q fever.

Keep in mind: Geographic overlap with human Q fever incidence does not establish hog-to-human causation.

Methods, limits & sources

The 2024 study analyzed 1,063 Texas serum samples from 101 counties, alongside a separate Hawaiʻi sample. Samples were collected through Wildlife Services surveillance between October 2018 and September 2023. The assay and positivity criteria matter; this is not a representative current census of all Texas hogs or a human infection probability.

Official guidance • human and veterinary health

What matters for people & animals

CDC describes human brucellosis exposure through infected animals and contaminated tissues or products.

USDA APHIS states that humans are considered resistant to pseudorabies virus strains. Other mammals, including dogs, can be affected.

Keep in mind: No single animal-test percentage predicts an individual’s risk. Use clinical and veterinary guidance, not this page, for exposure decisions.

Methods, limits & sources

CDC’s hunting guidance addresses contact with infected animals and tissues. APHIS’s April 30, 2026 Iowa/Texas announcement is a specific domestic-swine event, not a new statewide wild-pig prevalence estimate. TVMDL’s 2024 Texas hog-hunting dog case study is a veterinary resource; this page makes no unsupported claim about time from exposure to death. Contact a healthcare professional about a possible human exposure, or a veterinarian about an animal concern.

TPWD describes wild pigs as capable of carrying and transmitting at least 30 bacterial, fungal and viral diseases. That is a list of possible hazards, not evidence that each hog carries every disease.

Beyond Texas: separate research context

These studies have different sampling frames. They do not validate a current statewide Texas rate.

United States • 2014–2020 samples • serology

Parasite antibodies

Cleveland and colleagues reported 12.4% Trichinella and 40.8% Toxoplasma gondii antibody prevalence in their national sample.

Keep in mind: These are antibody results from sampled animals, not a meat-safety test or a current Texas prevalence estimate.

Methods, limits & sources

The 2023 Veterinary Parasitology paper compares these samples with an earlier 2006–2010 baseline. The reported South-region Trichinella figure was 13.4%; a regional subgroup is not interchangeable with Texas.

Oklahoma • published 2016 • exposure

Oklahoma pseudorabies

Gaskamp and colleagues reported 24.1% pseudorabies exposure in their sampled Oklahoma feral swine.

Keep in mind: An Oklahoma result does not corroborate a numerical prevalence range for all Texas hogs.

Methods, limits & sources

Interpret this as a separate regional study. Sampling period, local populations and testing methods must be consulted in the original paper before comparisons are made.

United States • 2014/2016 online papers • serum & kidney

Leptospira: sample type changes the question

A national serosurvey found 13% seropositivity among 2,055 animals. A separate targeted study found Leptospira DNA in 3.4% of 677 kidneys.

Keep in mind: Kidney PCR positivity does not itself prove active urinary shedding or quantify transmission risk. These percentages cannot be read as a decline.

Methods, limits & sources

The follow-up collected 677 kidneys and serum from 642 of the same animals in April 2012–September 2014, across 124 counties in 29 states selected for prior antibody-positive findings. Serum exposure in that selected sample was 53%. Different samples, specimens and tests answer different questions; lower kidney DNA detection does not establish lower human risk. The papers appeared online in 2014 and 2016, with journal issues in 2015 and 2017.

02 / The shared landscape

Water connects the whole landscape

Rooting, bank disturbance and fecal inputs can affect shared waterways. Livestock, pets, people, wildlife and runoff can all contribute; identifying a source requires measurements, not just nearby hogs.

Conceptual watershed illustration with a wild pig rooting near a creek, vegetation along the banks and cattle in the distance.
Conceptual illustration of a shared watershed — not a photograph or measured depiction of Spring Creek or Plum Creek.

Texas • San Jacinto basin • watershed planning

Spring Creek

TCEQ’s West Fork San Jacinto project documents water-quality concerns in a project area that includes Spring Creek.

Keep in mind: The linked TCEQ summary does not quantify a hog-attributable share or establish hogs as Spring Creek’s primary pollution source.

Methods, limits & sources

The project covers West Fork San Jacinto, Lake Creek, Spring Creek and Cypress Creek in Montgomery, Waller, Grimes and Harris counties. These are project-area counties, not a claim that every listed creek spans all four. The summary identifies the West Fork’s bacteria impairment in the 2014 Integrated Report and describes combinations of oxygen, nutrient and aquatic-community concerns in tributaries. It also describes Spring/Cypress monitoring and pollutant-source modeling. It does not support transferring every West Fork finding to Spring Creek.

Explore local conservation context on the Organizations page, including Bayou Land Conservancy.

Texas • Caldwell & Hays • reported historical comparison

Plum Creek

AgriLife’s manual reports 537 hogs removed over two years and a 48% decrease in E. coli in Plum Creek. HARC later describes a comparison with an adjacent area.

Keep in mind: This is a reported case comparison, not a verified controlled experiment or a guaranteed water-quality response to hog removal.

Methods, limits & sources

The Lone Star Healthy Streams Feral Hog Manual attributes the figures to “Feral Hog Project Accomplishments 2010.” HARC’s March 2024 account adds the adjacent-area comparison. The underlying 2010 monitoring report and its controls were not independently recovered for this review; neither a causal share nor a result transferable to other watersheds is established here.

Cooling behavior is only part of the picture

Pigs have limited effective sweating and use shade, wetting, wallowing and respiratory mechanisms to manage heat. Visiting water can contribute disturbance or waste, but behavior alone does not measure contamination or attribute a creek’s bacteria to hogs.

Read the sourced heat, water & mud chapter →

Methods, limits & sources

McKee et al. (2021) used microbial source tracking at 18 surface-water sites in Congaree National Park, South Carolina, with samples collected December 2017–June 2019. Swine markers were frequently detected, and marker concentrations were associated with elevated E. coli under study-specific conditions. This supports a measured pathway in that setting, not a Texas-wide attribution or a measurement from the illustrated creek.

03 / The shared landscape

Economic impact needs its context

A dollar figure means little without its geography, year and definition of loss. These estimates describe different scopes — and are neither a time series nor amounts to add together.

Read separately. The Texas figure is part of the Farm Bureau regional summary. The national estimate is a different synthesis with extrapolation, not the next bar in the same survey.

Three estimates. Different questions.
Reported estimateGeography & periodWhat it coversSource & interpretation
$871 millionTexas agricultural costsTexas component of a May 2025 summary.
Crop production year 2021; livestock costs include 2020.		Crop and livestock losses, pasture, property, control and other producer costs.Farm Bureau analysis ↗

Not a standalone current-year Texas damage census.

$1.6 billionRegional agricultural costs13-state combined summary, published May 2025.
11-state crop survey (2021 production year) plus 13-state livestock survey (2020 costs).		Combined producer costs across the two surveys, including costs beyond direct crop damage.Farm Bureau analysis ↗

Includes Texas; do not add $871 million again. It combines reference periods rather than one common observation year.

At least $3.4 billion annuallyU.S. composite estimateUnited States; synthesis published online October 2025, January 2026 journal issue. Underlying inputs span multiple years.Agriculture, health, environment and property; known costs combined with extrapolations.McKee et al. full study ↗

A composite lower-bound estimate, not another row from the Farm Bureau surveys.

Methods, limits & sources

Farm Bureau describes a 2022 survey of more than 11,000 crop producers about six crops and the 2021 production year, and a separate 2023 survey of more than 8,000 livestock producers. Its category descriptions identify 2020 livestock property and pasture costs. Although the article calls the combined result annual losses, the underlying reference years should not be collapsed into one shared year. The $3.4 billion paper integrates published evidence and extrapolated costs; the USDA funding announcement is additional policy context, not the originating estimate. None of these figures should be summed or used as a trend against differently scoped older Texas estimates.

Compiled by Texas Hog Dispatch from the sources linked above. Historical measurements retain their original scope; no county-record timestamp is used as an editorial verification date.

Data License

The dataset behind this tracker — county-level population estimates, activity levels, trajectories, and the CSV / PDF exports derived from them — is released under a Creative Commons Attribution 4.0 (CC BY 4.0) license. You are free to use, share, adapt, and republish the data for any purpose, including commercially, with attribution to Texas Hog Dispatch.

This license applies specifically to the underlying dataset. It does not cover the Texas Hog Dispatch name, logo, seal, site design, written copy, or any other brand assets — those remain the property of Texas Hog Dispatch and are not licensed for reuse under CC BY 4.0. Figures quoted above from third-party agencies and journals remain subject to their publishers' own terms.

Contact for Data Inquiries

Press and researcher questions about the figures shown on this page can be directed to data@texashogdispatch.com.

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