The Swine Health Information Center, launched in 2015 with Pork Checkoff funding, protects and enhances the health of the US swine herd by minimizing the impact of emerging disease threats through preparedness, coordinated communications, global disease monitoring, analysis of swine health data, and targeted research investments.
On the latest episode of SHIC Talk, host Barb Determan welcomes SHIC Executive Director Dr. Megan Niederwerder and guests Dr. Michael Chetta and Josh Holtkamp of Talent Metrics Consulting. Dr. Chetta and Josh discuss results of their research project addressing pig caretaker motivation for performing biosecurity tasks. Their results reveal simple, low cost ways for owners and managers to increase biosecurity task compliance with rewards and motivation.
Porcine sapovirus (PoSaV) is an emerging pathogen that causes diarrhea in suckling and weaned pigs. Accurate detection and isolation of circulating PoSaV strains is needed to characterize infection and develop preventative strategies. To help advance PoSaV research, the Swine Health Information Center funded a study conducted by Dr. Qiuhong Wang at The Ohio State University and Dr. Thomas Petznick at Veterinary Health Services, Omaha, Nebraska. Recently published findings in the journal Veterinary Microbiology detail the successful isolation of contemporary PoSaV field strains from US swine herds, an essential milestone that could lead to more effective diagnostic tools and future vaccine development.
PoSaV is a very environmentally stable virus that can persist and spread within swine herds, making it a challenging issue especially in high-health production environments. This SHIC-funded study addresses gaps in PoSaV knowledge and has objectives to improve understanding of the virus, provide tools for diagnosis, and develop potential mitigation strategies, such as vaccines, for PoSaV infection control. Overall goals of advancing PoSaV knowledge are to reduce potential economic losses associated with post-weaning diarrhea, reduced weaning weight, and poor growth performance in US swine.
Find the complete paper here: Aryal, B., et al., 2025, Veterinary Microbiology. doi.org/10.1016/j.vetmic.2025.110709
Sapoviruses belong to the Caliciviridae family, a group of non-enveloped viruses known for infecting a range of animal species, including pigs and humans (Oka et al., 2015). Among the many genogroups identified, GIII PoSaV is the most common genogroup found in pigs worldwide (Lyoo et al., 2020). Infected pigs, particularly those in the weaning and post-weaning stages, can show mild to moderate diarrhea or remain clinically healthy while shedding the virus in feces (Kuroda et al., 2017).
Though PoSaV infections are generally self-limiting, studies have shown that affected piglets may suffer a loss in expected weaning weight of roughly 1.0 – 2.0 pounds per head (Shen et al., 2022). These seemingly small performance gaps can add up significantly across large production systems. Co-infections with other enteric pathogens, such as rotavirus, swine enteric coronaviruses, and Escherichia coli, may worsen clinical signs and further erode productivity.
Historically, the growth and culture of PoSaV outside the animal host has been a challenge. Only two older reference strains, Cowden and LL14, had been successfully propagated in laboratory cell lines, and both required the presence of bile acids to replicate (Chang et al., 2004). Lacking consistent isolation systems, the study of current field strains and the ability to design targeted control measures have been limited.
Due to the increasing association of PoSaV with diarrhea in young pigs, underdiagnosis of field cases, and the lack of progress in propagating the virus, a primary objective of this study sought to isolate contemporary PoSaV strains and develop tools to perform cell culture isolation of circulating PoSaV. To conduct this study, five sow farms in Nebraska were sampled that had piglets exhibiting PoSaV-suspected gastroenteritis outbreaks. Samples were collected between November 2023 – May 2024 from piglets 12 to 28 days of age with clinical signs of diarrhea. A total of 35 fecal and seven small intestinal samples were obtained for testing.
All samples were evaluated for the presence of PoSaV GIII by PCR. Molecular PCR screening revealed that 60% (25/42) of the samples were positive for GIII PoSaV, confirming a significant presence in the herds. Four of five farms tested positive for PoSaV based on PCR results, with detection rates of 33% – 100%. Detection of GIII PoSaV from the samples in this study indicates that GIII continues to be the main genogroup in suckling and post-weaning pigs. The 60% prevalence of PoSaV in the clinically affected pigs is consistent with previous findings, providing evidence that PoSaV could be a major enteric pathogen responsible for diarrhea in younger piglets. However, diagnostic testing was not performed for the detection of other enteric viruses such as rotavirus or astrovirus.
To further characterize the viruses detected, one representative PCR-positive sample (Ct < 20) from each of the four farms was selected for NGS. Based on near-complete nucleotide sequences and amino acid sequences of non-structural proteins, three of the samples from three different farms were similar, suggesting a shared more recent common ancestor. However, the sample from the fourth farm branches separately suggesting it may have undergone evolutionary changes that differentiate it from other strains. The four virus strains are genetically similar but are different from classical reference strains, indicating potential evolutionary changes. These findings emphasize the need for continued surveillance and molecular characterization of identified strains.
In addition to the genetic characterization, the investigators achieved successful virus isolation in two different porcine cell lines, LLC-PK1 (porcine kidney) and ST (swine testicular), marking the first-ever propagation of PoSaV strains in ST cells. Out of the 25 positive samples, 8% grew in ST cells and 16% in LLC-PK1 cells. No isolates were recovered in the IPEC-J2 intestinal cell line, even though it had previously been used successfully with historic strains.
The ability to culture PoSaV in the cell lines within this study provides immediate and long-term potential benefits for the pork industry, such as improved diagnostic tools. Further, the discovery that ST cells can support PoSaV growth could accelerate the future development of a commercial PoSaV vaccine. Having live isolates means researchers can refine PCR assays specific to the strains currently circulating in North American farms. More accurate diagnostics help veterinarians distinguish PoSaV from other causes of diarrhea, improving treatment and biosecurity decisions. Researchers plan to study the pathogenesis of these new isolates in greater depth and explore how different environmental or management factors might influence viral persistence within herds.
Better understanding of PoSaV biology gives the industry new tools to diagnose, monitor, and manage swine enteric health more precisely, helping ensure pigs transition more smoothly through weaning and maintain consistent growth. Developing new knowledge and tools for PoSaV aligns with SHIC’s mission to mitigate emerging disease threats and protect the health of the US swine herd.
References
Chang et al., 2004. Journal of Clinical Microbiology, 42: 4641–4646.
Kuroda et al., 2017. Veterinary Microbiology, 208: 91–98.
Lyoo et al., 2020. Transboundary and Emerging Diseases, 67: 1704–1716.
Oka et al., 2015. Virus Research, 211: 146–159.
Shen et al., 2022. Pathogens, 11: 1191.
The Swine Health Information Center’s Standardized Outbreak Investigation Program (SOIP) includes a downloadable Word-based form and a web-based application to conduct standardized outbreak investigations. The program and tools were developed in response to an industry need for consistency in data collection and results across different investigators, outbreaks, and farms. Prompted and funded by SHIC, the web-based application has been available for nearly two years after development by program lead, Dr. Derald Holtkamp, Iowa State University, along with colleague, Dr. Kate Dion. Using aggregated outbreak information, investigators share herein detailed lessons learned through SOIP development and industry use.
In 2021, SHIC funded the development of the SOIP through a working group of 14 swine veterinarians formed to develop the terminology, approach, and instrument. In 2023, the tool was endorsed by the American Association of Swine Veterinarians Board of Directors for use in conducting outbreak investigations for swine pathogens. A web-based version for the standardized application was launched in 2024 with funding from SHIC, increasing the ease by which veterinarians can use and capture data from investigations in a secure database.
Outbreak investigations offer valuable opportunities to identify and prioritize biosecurity hazards. Dr. Holtkamp noted the saying, “Never let a good crisis go to waste.” While outbreaks are undeniably a crisis, they also present a chance to learn—though that learning is not automatic. When outbreak investigations are conducted comprehensively and systematically with the goal of identifying biosecurity hazards within the production system, they consistently generate insights that make the time and resources invested worthwhile.
SOIP Key Findings
▪️Each entry event where a pathogen-carrying agent enters the farm poses a risk. Employee entry is the most frequent entry event (about 6,158 events annually for a 4,000-sow farm).
▪️Swine movements (cull sows and weaned pigs) were most often assigned a high hazard rating, followed by mortality removal, employee entry, and repairs inside barns.
▪️Outbreak investigations not only identify biosecurity hazards but also highlight systemic weaknesses in execution, planning, and monitoring. Industry-wide outbreak investigation data enables prioritization of resources to strengthen biosecurity.
Lessons learned from conducting outbreak investigations. As of October 2025, the SOIP database contained data for 87 completed investigations on sow farms across 24 different companies. Most of the investigations were done for PRRSV (n = 65) and PEDV (n = 19). The results presented here reflect all 87 investigations regardless of pathogen. While biosecurity risks vary by producer and farm, analyzing data at the industry level reveals where time and resources may need to be prioritized to strengthen biosecurity.
Frequency of entry events. Entry events occur when one or more pathogen-carrying agents, defined as something that can be infected or contaminated with a pathogen, enter the farm. Each entry event creates an opportunity for pathogens to enter the herd. The frequency of these events depends on herd size and the length of the investigation period. Some events occur continuously, such as air and water entry, while others occur periodically but are frequently unobserved, like rodents, wild animals, insects, and non-swine domestic animals. All other entry events on sow farms occur periodically and are generally observable. Among these, employee entry is by far the most frequent; each time an employee enters a barn, it counts as an entry event. On average, 118.43 employee entries occur per 1,000 sows over a 4-week period. For a typical 4,000-sow farm, this equals about 6,158 events annually (Table 1).
Table 1. Frequency of entry events on sow farms, for 87 investigations in the SOIP database.
Entry events rated high most frequently. A key component of the investigation is a subjective evaluation of how likely each entry event may be associated with an outbreak. This evaluation is based on information collected in the investigation form. Investigator(s) are responsible for making this determination and assigning a hazard rating of high, medium, or low to each entry event. Although an objective scoring system could offer advantages, a subjective approach allows investigators to weigh all available information within the broader context, including site location, season, weather conditions, and other factors that may influence the assigned hazard ratings.
Entry events most frequently rated high were swine movement events. Specifically, cull sows hauled from the farm received a high rating in 38 of 80 investigations where a rating was assigned, and weaned pigs hauled from the farm were rated high in 36 of 84 investigations (Table 2). The total number of ratings does not equal 87 for all entry events because ratings were not assigned when an event did not occur during the investigation period, and in a few cases, investigators omitted ratings even when the event did occur. Rounding out the top five high-risk entry events were mortality removal, on-farm employee entry, and repairs inside barns.
Table 2. Frequency with which entry events were rated high, medium and low, for 87 investigations in the SOIP database.
Lack of knowledge about the production processes. Biosecurity hazards originate within production processes, so identifying them requires a thorough understanding of those processes. Biosecurity hazards are often overlooked due to an incomplete knowledge of the production processes. Key details include: 1) procedural aspects (how tasks are performed, by whom, and when), 2) structural aspects (where tasks occur, including site and building layout and design), and 3) resource aspects (the tools and materials available to complete tasks). Many aspects of the production process are not fully understood by veterinarians or production managers, making biosecurity hazard identification challenging. This knowledge gap is even greater when critical activities are outsourced to third-party providers, such as livestock transport, loading crews, or manure removal. In fact, one of the most valuable outcomes of outbreak investigations is often the realization, “I don’t know, but I need to find out.”
Poor execution. Although biosecurity control measures are often well-intentioned, they frequently fail due to poor execution. Effective biosecurity requires getting the procedural, structural and resource aspects right, which frequently does not happen in practice. Use of chemical disinfection highlights these challenges. Personnel on farms or in truck washes frequently know which chemical disinfection to use and at what concentration, but it is rare that chemical disinfectants are applied at the intended concentration. They frequently don’t know how to dilute the chemicals (i.e., how many ounces to include per gallon of water), lack the proper equipment to do so, or apply the disinfectants incorrectly. A common example of the latter is to dilute the disinfectant that is poured into the injector well of a power washer. As it is applied with the power washer, it is diluted again at a rate that is seldom known, yielding the application of disinfectant with an unknown concentration that is likely much more diluted than desired.
No plans for rare or unexpected happenings. Weather, holidays, employee absences, equipment breakdowns, and urgent needs for supplies or equipment all occur on swine farms without exception. However, it is common to see these occurrences lead to significant biosecurity hazards. Just a few examples include equipment or supplies entering without any decontamination, repair personnel entering the site without showering in, and supplies urgently needed being transferred from other swine sites. These things happen because the production processes are built for the usual. Planning for the rare or unusual is often not done. The result is too many outbreaks where the unusual happened and the personnel on the ground dealt with it the best they knew how, but created biosecurity hazards that led to an avoidable disease outbreak.
Too little effort is spent on monitoring the process. Outbreak investigations are useful for identifying biosecurity hazards and if done systematically and relatively comprehensively, they can help identify critical control points. Critical control points are steps in the production process that are important for preventing outbreaks. For example, if trailers that enter a farm to haul cull sows also deliver them to cull markets or haul culls from other farms known to be positive for PRRSV or PEDV, then washing, disinfecting, and thoroughly drying those trailers between loads should be considered critical control points. We need to get them right nearly every time. For washing, we may want the removal of organic matter to be complete. For disinfection we may want the disinfectant applied at a desired concentration (e.g. 1:64). For drying, if done by TADD, we may want the surface temperature of the trailer to reach 160 degrees F and be maintained at that temperature for at least 10 minutes. Too often, these are left to chance. Nothing is monitored, no data is collected and there are no plans to periodically audit the processes to assure that the critical control points are being done consistently and correctly.
Industry encouraged to utilize SOIP. While each investigation provides valuable insights, a centralized database is essential for identifying patterns and learning from multiple investigations over time. The SOIP investigation database offers a unique opportunity to leverage the collective experience of the entire industry. The web-based application is available to all producers and veterinarians. Access to the application can be requested via email at [email protected].
Submissions to the Iowa State University Veterinary Diagnostic Laboratory have recently included a growing number of pig cases with a severe lung lesion pattern called diffuse alveolar damage (DAD), a syndrome historically rare in swine. To understand what may be driving this change, the Swine Health Information Center funded a study led by Dr. Marcelo Almeida to investigate the etiology of this emergent swine respiratory disease syndrome. A total of 42 DAD cases were reviewed by veterinarians and tested by PCR for common respiratory viruses, including PRRSV, IAV, and PCV2, and next generation sequencing to detect other viruses. While many pigs were infected with common respiratory pathogens, no single virus consistently explained the DAD lesions, suggesting that controlling PRRSV, IAV, and PCV2 through vaccination and sound herd management remains the best strategy available today to help reduce the risk of this severe lung damage in pigs.
Find the industry summary for SHIC project #24-043 here.
In veterinary medicine, DAD is most frequently observed as a syndrome in cattle, referred to as atypical interstitial pneumonia, which is associated with ingested pneumotoxins, epitheliotropic viral agents, and noxious gas inhalation (Doster et al., 2010; Carvello et al., 2022; Chien et al., 2022; Haydock et al., 2022). Unlike cattle, diffuse alveolar damage is poorly documented or characterized in pigs, with only rare reports of compatible lesions associated with porcine respiratory coronavirus infection and a historical association with PCV2 (Carvallo et al., 2022; Jung et al., 2007).
In pigs with respiratory disease complex, expiratory dyspnea – often referred to as “thumping” – is caused by decreased oxygenation and lung compliance due to fluid or cellular expansion of the interstitium. This pattern of interstitial pneumonia occurs as a sequela of systemic insult due to endotoxemia and bacterial or viral infections and is most often associated with PRRSV and PCV2 infections in swine. In contrast, DAD, the focus of this study, is a lesion characterized by synchronous necrosis of respiratory pneumocytes and/or capillary endothelium that compromises diffusion of gases between the alveolar space and circulating red blood cells (Carvallo et al., 2022).
In the absence of intensive supportive care, DAD progresses to respiratory failure and/or cardiovascular collapse and death in pigs. Surviving pigs typically face a prolonged recovery and sustained clinical signs with adverse production impacts due to the severe and often irreversible damage to lung architecture, leading to interstitial fibrosis and permanently diminished oxygenation capacity.
The study described herein was a retrospective exploratory study investigating possible causes for an emergent syndrome in pigs presenting with lesions of DAD. The case definition for this retrospective study consisted of porcine accessions submitted to the ISU-VDL for diagnostic investigation, including fresh and fixed lung tissue, a history of severe respiratory disease, and histologic lesions consistent with DAD characterized by necrotizing and lymphohistiocytic pneumonia with hyaline membrane formation.
Study objectives sought to 1) investigate the etiology of the emergent syndrome of severe necrotizing interstitial pneumonia with DAD in swine, and 2) determine whether the escalating frequency of this syndrome in pigs with respiratory disease complex is a function of enhanced virulence of routine viral agents, or the result of an undetected novel co-infection. In addition, a comprehensive interrogation of samples was performed with whole-genome sequencing (WGS) and in situ imaging techniques. Researchers explored genomic changes in detected viral pathogens and assessed genetic homology of endemic agents, screened tissues for previously undetected or emergent novel viral agents that may contribute to this syndrome, and further characterized the pathology of DAD to confirm in situ localization of known viral pathogens via direct detection methods (immunohistochemistry).
Forty-two swine cases submitted to the ISU-VDL met the selection criteria and were included in this study. Most cases were diagnosed with PRRSV (71.4%), IAV (35.7%), PCV2 (16.7%), or a combination of two or three of those pathogens (26.2%). PRRSV, IAV, and PCV2 were detected within lesions consistent with those pathogens in 24 (57.1%), 13 (31.0%), and nine (21.4%) cases, respectively. However, none of those pathogens were detected in association with DAD lesions.
NGS revealed the presence of contemporary PRRSV lineages, IAV subtypes, and PCV2 genotypes in cases associated with DAD. In addition to PRRSV, IAV, and PCV2, 17 other viruses were detected but none were consistently detected in all cases. Parvoviruses were detected in 45% of the cases, with parvovirus 2 and 7 detected in 21.4% and 19% of the cases, respectively. Researchers report that evidence to support the involvement of any of those 17 viruses in the causation of DAD is lacking.
The literature regarding DAD in pigs is scarce and diagnostic investigations have been limited to PRRSV, IAV, PCV2, and PRV. Therefore, in this retrospective exploratory study, researchers expanded the search for other pathogens. However, the lack of specific lesions or consistency of detection for those pathogens suggests a limited role, if any, in the occurrence of DAD in pigs.
The recent increase in cases of DAD in pigs observed at the ISU-VDL cannot be explained by the data collected and analyzed for this project; nevertheless, it confirms the involvement of the three main viral etiologies of the porcine respiratory disease complex in association with DAD lesions. It is unknown how PRRSV, IAV, and PCV2 infection results in this severe pattern of histological lesions or the cause of the sharp increase in swine cases of DAD. It is possible that cytokine storms or other immunologic events triggered by unknown factors in cases of severe disease caused by PRRSV, PCV2, and IAV induce DAD lesions; however, why and when that happens remains unclear.
Researchers conclude that control of related viral infections (PRRSV, PCV2, IAV) through vaccination, management practices, and disease elimination, when possible, is likely the most effective way of preventing the manifestation of DAD in pigs.
References
Doster AR. Bovine atypical interstitial pneumonia. Vet Clin North Am Food Anim Pract. 2010 Jul;26(2):395-407. doi: 10.1016/j.cvfa.2010.03.002. Epub 2010 May 14
Carvallo FR, Stevenson VB. Interstitial pneumonia and diffuse alveolar damage in domestic animals. Vet Pathol. 2022 Jul;59(4):586-601.
Chien RC, Sorensen NJ, Payton ME, Confer AW. Comparative Histopathology of Bovine Acute Interstitial Pneumonia and Bovine Respiratory Syncytial Virus-Associated Interstitial Pneumonia. J Comp Pathol. 2022 Apr;192:23-32.
Haydock LAJ, Fenton RK, Sergejewich L, Squires EJ, Caswell JL. Acute interstitial pneumonia and the biology of 3-methylindole in feedlot cattle. Anim Health Res Rev. 2022 Jun;23(1):72-81.
Jung K, Alekseev KP, Zhang X, Cheon DS, Vlasova AN, Saif LJ. Altered pathogenesis of porcine respiratory coronavirus in pigs due to immunosuppressive effects of dexamethasone: implications for corticosteroid use in treatment of severe acute respiratory syndrome coronavirus. J Virol. 2007;81(24):13681-13693.
As an outcome of the Swine Health Information Center Wean-to-Harvest Biosecurity Research Program, in partnership with the Foundation for Food & Agriculture Research and Pork Checkoff, a newly published paper in Veterinary Sciences outlines risk and protective factors for PRRSV outbreaks identified through an industry-wide biosecurity survey. Utilizing a questionnaire to gather data, the survey project completed in April 2025 reported biosecurity practices across 3,680 sites. In a second study, 95 wean-to-harvest sites were followed with monthly oral fluid testing for PRRSV. Researchers characterized which practices increased or decreased the likelihood of a PRRS outbreak. Risk factors included transporting pigs of unknown PRRSV status, rendering mortalities, and employees working across multiple sites living together. Protective factors included assigned vehicle parking, farm-owned equipment, and overnight downtime for caretakers working across multiple sites.
Find the full paper in Veterinary Sciences here and the industry summary for project #23-029 on this page. Read more about the Wean-to-Harvest Biosecurity Research Program here.
Led by Drs. Mariah Musskopf and Gustavo Silva at Iowa State University, this study assessed current bioexclusion practices among a diverse group of producers across swine-producing states in the US. In addition, the study developed methods that veterinarians, production managers, and producers could implement to improve on-farm biosecurity including the development of a risk assessment tool. Overall, findings showed that biosecurity on wean-to-harvest sites is inconsistent across the industry and that tools for increasing biosecurity could include relatively simple practices such as bench entry.
To assist with the management of increased PRRS activity detected during winter months, SHIC is highlighting the project information regarding risk and protective factors from PRRSV outbreak data to help producers, veterinarians, and other stakeholders apply key learnings from the project. In the forest plot graph (Figure 1), odds ratios for various biosecurity and management practices associated with PRRSV outbreaks are displayed. Practices with odds ratios above 1 indicate increased odds of outbreak (red dots), while those below 1 suggest protective effects (green dots).
Figure 1. Risk and protective factors for PRRSV outbreaks based on biosecurity questionnaires and monthly oral fluids testing for PRRSV. Reprinted from Musskopf, M., et al., Vet. Sci. 2025, https://doi.org/10.3390/vetsci12101000.
Among the practices evaluated, transporting pigs with unknown PRRSV status, using rendering for mortality management, and workers cohabitating with others who work swine-related jobs were significantly associated with higher likelihood of PRRS outbreaks. Researchers noted that sites where employees cohabitated with others involved in swine-related work had 6.15 times higher odds of a PRRS outbreak (95% CI: 1.51–25.09, p = 0.011). Sites using rendering for carcass disposal had 6.47 times higher odds of a PRRS outbreak compared to sites that did not use rendering (95% CI: 1.62–25.84, p = 0.008).
In contrast, the researchers said that practices such as maintaining a defined parking space decreased the likelihood of a PRRSV outbreak (OR = 0.07, 95% CI: 0.01–0.35, p = 0.001). Further, sites that used exclusive pumping equipment owned by the farm and used at a single location were associated with significantly lower odds of a PRRS outbreak (OR = 0.07, 95% CI: 0.01–0.43, p = 0.003). Practices or on-farm characteristics found to reduce the likelihood of a PRRSV outbreak are highlighted in green and suggest a protective effect.
These findings highlight the need for targeted biosecurity measures, especially in the finisher phase, where the risk of PRRSV outbreaks is higher. Results underscore the importance of implementing effective biosecurity practices, such as regular washing, downtime, and preventing sick animal transport, to mitigate the risk of PRRSV transmission and protect the health of the US swine herd.
Reference
Musskopf, M.; Peterson, T.; Machado, I.; Tran Pham Tien, T.; Kirwa, E.; Carnevale de Almeida Moraes, D.; Cezar, G.; Mil-Homens, M.; Li, P.; De Conti, E.; et al. Assessment of the Relationship Between Bioexclusion Practices Applied in Wean-to-Harvest Sites and PRRS Outbreaks. Vet. Sci. 2025, 12, 1000. https://doi.org/10.3390/vetsci12101000.
Foundation for Food & Agriculture Research
The Foundation for Food & Agriculture Research (FFAR) builds public-private partnerships to fund bold research addressing big food and agriculture challenges. FFAR was established in the 2014 Farm Bill to increase public agriculture research investments, fill knowledge gaps and complement the U.S. Department Agriculture’s research agenda. FFAR’s model matches federal funding from Congress with private funding, delivering a powerful return on taxpayer investment. Through collaboration and partnerships, FFAR advances actionable science benefiting farmers, consumers and the environment.
Swine Health Information Center
The Swine Health Information Center, launched in 2015 with Pork Checkoff funding, protects and enhances the health of the US swine herd by minimizing the impact of emerging disease threats through preparedness, coordinated communications, global disease monitoring, analysis of swine health data, and targeted research investments. As a conduit of information and research, SHIC encourages sharing of its publications and research. Forward, reprint, and quote SHIC material freely. For more information, visit http://www.swinehealth.org or contact Dr. Megan Niederwerder at [email protected] or Dr. Lisa Becton at [email protected].
This month’s Domestic Swine Disease Monitoring Report shows PRRSV has reached its highest percentage of PCR‑positive case submissions (48.5%) in the wean‑to‑market category since 2018, underscoring the need for strengthened monitoring, biocontainment, and biosecurity practices. In November and December 2025, PEDV case positivity increased notably, reaching 11.5% in adult/sow farms (the highest level recorded in 2025) and 25.2% in facilities (the highest level observed since 2023). A bonus page features retrospective insights into the 2025 Swine Disease Reporting System, offering SDRS developments and highlighting pathogen trends throughout the year. In this month’s podcast, Dr. Kurt Kuecker, senior veterinarian at HANOR, discusses worker, transport, and mortality management biosecurity practices, along with strategies for disease containment and response during PEDV and PRRSV outbreaks.
Information on foot-and-mouth disease, African swine fever, and pseudorabies activity is included in this month’s Global Swine Disease Monitoring Report. FMD has been detected in Cyprus for the first time since 2008. Its presence was reported by authorities in the Turkish Cypriot-administered area. In Spain, preliminary results of ASF investigations have not confirmed a link between recent outbreaks and a research facility in Catalonia which had been identified as a potential concern. In South Africa, authorities reported a substantial increase of 165 additional FMD outbreaks in December 2025, bringing the total number of ongoing outbreaks to 583. In Hungary, authorities report to WOAH an outbreak of pseudorabies at a commercial pig farm, marking the country’s first case since eradication in 2021.
PRRS Cumulative Incidence for MSHMP
PEDV Cumulative Incidence for MSHMP
Four PRRSV variants are classified as Variants Under Monitoring (VUMs) category 2 or higher and are described in this month’s report: Variants 1C.5.32 remains a VUM Category 4, 1C.2 and 1C.5 remains VUM Category 3, and 1H.18 has been reclassified as Category 2 from a previous Category 1 (this change is reflected in a new variant-specific situation report). Previous reports for all variants ever classified as VUM Category 2 or higher remain available.
