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.
According to a World Organisation for Animal Health report, African swine fever has been confirmed in Taiwan on a pig farm located on the western coast of the island nation (Figure 1). This is the first ASF occurrence in Taiwan. Samples were sent to the National Reference Laboratory for diagnosis on October 21, 2025, due to increased mortality rates. On October 25, 2025, the outbreak was confirmed as ASF. All control measures have been implemented since October 21, 2025. There were 301 susceptible pigs on the affected farm with 109 ASF cases noted and 106 deaths. The remaining 195 pigs on the farm were euthanized. WOAH reports that all appropriate response actions are being taken in Taiwan to limit the spread.
Taiwan is approximately 100 miles (160 km) off the southeastern coast of mainland China, separated by the Taiwan Strait. However, the closest point is much narrower, with some smaller Taiwanese-controlled islands, like Kinmen, being just a few miles from the Chinese mainland. Taiwan’s northernmost island is only 79 miles (128 km) from the northernmost island of the Philippines, Mavulis Island in Batanes. Â
Taiwan had recently become the only country in Asia formally recognized by WOAH as free from both ASF and classical swine fever. This dual recognition was solidified in May 2025 during the WOAH General Assembly, following Taiwan’s self-declaration of freedom from ASF on July 2, 2024. The ASF-free status is nullified by the recent diagnosis.Â
The CSF-free status was the culmination of an extensive, decade-long process that began with the last documented case in 2015. Taiwan submitted its formal CSF-free application to WOAH in August 2024, which was approved by the Scientific Commission in February 2025. This accomplishment builds on Taiwan’s earlier success in eliminating foot-and-mouth disease virus, from which it was declared free by WOAH in 2020.
Please click here to provide your input for SHIC’s 2026 Plan of Work before our December 1, 2025, deadline! The 2026 Plan of Work is currently under development and will be built around SHIC’s five strategic priorities: 1) improving swine health information, 2) monitoring and mitigating risks to swine health, 3) responding to emerging disease, 4) surveillance and discovery of emerging disease, and 5) swine disease matrices. Find the 2025 Plan of Work here for reference.
A study funded by the Swine Health Information Center Wean-to-Harvest Biosecurity Research Program, in partnership with the Foundation for Food & Agriculture Research and Pork Checkoff, assessed the development of an effective and practical biosecurity entrance system. Led by Dr. Teng Lim at the University of Missouri, various biosecurity interventions were evaluated for their effectiveness, including air showers, disinfectant spraying, disinfectant fogging, and their combinations, on reducing bacterial and viral contamination of cloth, skin, and hair surfaces. While full-body showering was confirmed as the most effective method, a system combining air showers with disinfectant spraying and hair nets performed similarly, revealing opportunities and challenges with novel methods.Â
Find the industry summary for Swine Health Information Center project #23-049 here.Â
Traditional biosecurity measures such as shower-in/shower-out and Danish entry systems (DES) are effective but can be difficult to consistently implement due to time requirements and compliance by farm personnel. Farm-specific coveralls and human hygiene are critical barriers to pathogen entry. However, overlooked aspects such as worker hair, clothing, and dirty hands remain significant reservoirs for pathogen transmission. Human hair is a naturally shedding material that can carry and release pathogens when not properly covered with hair nets or sanitized through physical (showering) or chemical means. Since a single lapse in protocol can lead to pathogen introduction, developing alternative or supplemental methods that are practical, efficient, and acceptable to workers is essential.Â
Objectives of this project were to evaluate a combination of innovative biosecurity-effective entry systems for commercial pig farms as replacement options for the strenuous shower-in and shower-out system. The study was designed to evaluate the effectiveness of multiple biosecurity interventions—including air shower (AS), disinfectant spraying (DS), disinfectant fogging (DF), and their combinations—with and without integration of the DES and hair nets (HN). Another treatment was the Modified-DES (MO.DES), which was the DES but instead of hand washing, it utilized hand sanitizer. Three representative surfaces, including coverall or t-shirt, leather or pigskin (representing human skin), and faux fur (representing human hair), were contaminated with two bacteria, Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative), and two viruses, canine distemper virus (CDV, enveloped) and feline calicivirus (FCV, non-enveloped), to assess the efficacy of the treatment methods.Â
A commercial AS unit was installed for personnel decontamination. For the DS and DF components, a 7-ft × 4-ft outdoor storage shed was repurposed as a dedicated chamber for disinfectant application. Slightly acidic electrolyzed water (SAEW) was used as the disinfectant and was prepared at available chlorine concentrations of 50, 100, 200 and 300 mg/L. SAEW was generated by electrolyzing tap water with a brine/electrolyte solution containing 107 g NaCl and 40 mL of 12 M HCl in 500 mL distilled water, using a commercial electrolyzed water generator. Â
Two entry protocols were evaluated: the Danish entry system, which involved the use of hand soap, farm-specific clothing, and dedicated footwear; and the modified Danish entry system, which used hand sanitizer and hair nets in addition to farm-specific clothing and footwear. Treatments were tested with and without the Danish entry system, hair nets, and a modified Danish entry system using hand sanitizer. Â
For the evaluation of bacterial load reduction, standard plate count methods were used to evaluate the effectiveness of the individual and/or combined treatment systems in reducing E. coli and S. aureus contamination from cloth, skin, and hair surfaces. For the viral load reduction test, cycle threshold (Ct) values were measured using real-time PCR on samples recovered from control and treated sample surfaces, and were evaluated for the effectiveness of the individual and/or combined treatment systems.Â
Overall, results demonstrated that while the single-step methods including air showers, disinfectant spraying, and disinfectant fogging were largely ineffective on their own, integrating the Danish entry system or hair nets significantly enhanced both bacterial and viral reductions. The bacterial reduction study (E. coli and S. aureus) revealed that disinfectant spraying and air showering with disinfectant spray achieved over 2-log reduction, while Danish entry system or hair net-enhanced combinations reached 3–4-log reductions. While the full shower remained most effective, particularly for hair (5-log reduction), the air shower plus disinfectant spray plus hair net treatment performed similarly. The modified Danish entry system eliminated bacteria to undetectable levels on hands. Across all treatments, E. coli exhibited consistently higher susceptibility to treatment than S. aureus.Â
For the viral reduction tests (FCV and CDV), only Danish entry systems or hair net-based combinations achieved meaningful reductions, with two combinations performing close to the full shower protocol: Â
1) air shower, disinfectant spray and Danish entry systemÂ
2) air shower, disinfectant spray and hair net Â
Incorporation of Danish entry system markedly increased viral Ct values (higher Ct values indicate low viral load), with mean Ct values above 35, significantly higher than controls and single-step treatments. Combinations containing Danish entry system, particularly air shower plus Danish entry system, disinfectant fogging plus Danish entry system, and the combination of air shower, disinfectant spray and Danish entry system, produced Ct values >35 with several undetectable replicates, representing significantly greater viral reduction than all non-Danish entry system treatments. Â
Overall, results of this study demonstrate that Danish entry systems and hair nets are critical additions for effective microbial control during farm entry. Further, the use of an alcohol-based hand sanitizer as part of a modified Danish entry system and multi-step combinations can offer practical, effective alternatives in settings where full-body showering is not feasible.Â
Foundation for Food & Agriculture ResearchÂ
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 US Department of 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. Connect: @FoundationFARÂ
Swine Health Information CenterÂ
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].
A study funded by the Swine Health Information Center Wean-to-Harvest Biosecurity Research Program, in partnership with the Foundation for Food & Agriculture Research and Pork Checkoff, investigated the development and evaluation of an electrostatic precipitator (ESP) prototype to mitigate airborne spread of pathogens under farm conditions. Led by Dr. Montserrat Torremorell at the University of Minnesota, the study evaluates the utility of an ESP to remove airborne particles from aerosols, including PRRSV. The ESP demonstrated high effectiveness, comparable to or slightly exceeding a MERV-16 filter, in removing airborne particles and over 99% removal of PRRSV. While the analysis showed potential for the ESP as a biosecurity tool, economic considerations, challenges related to scalability, adapting the design to swine farms, and maintenance protocols will require further commercial exploration.Â
Find the industry summary for Swine Health Information Center project #23-009 here.Â
Study objectives were to develop an ESP prototype designed with the goal of installation and use in a swine farm and evaluate its general performance, ability to resist the farm environment, identify prototype shortcomings, and measure energy use. Overall, intended outcomes were to evaluate the potential feasibility of an ESP as a biosecurity measure to minimize pathogen introduction through aerosols and/or maximize the biocontainment of airborne viruses post-outbreak. Â
The study focused on assessing the detailed capabilities of the ESP system to remove airborne particles. Results demonstrated that the technology is highly effective at removing general airborne particulate matter. When compared to the MERV-16, widely considered the gold standard for high-efficiency filtration in controlled environments, the ESP prototype achieved similar or enhanced performance using its non-mechanical, electrostatic method. These results suggest potential opportunities for farms to shift to technologies that would be highly effective without the rapid pressure drop and replacement burden associated with using mechanical air filration.Â
A commercially available ESP was used and tested for its ability to collect airborne particles in the ASHRAE 52.2 wind tunnel in the UMN Department of Mechanical Engineering. The ESP was assessed in a controlled laboratory setting to assess the particle collection efficiency and to confirm particle size distribution. The size distribution measurements were conducted using a Size Mobility Particle Scanner and Optical Particle Scanner, covering a particle range from 10 nm to 10 µm. After laboratory characterization of the ESP was completed, the ESP was installed within a wean-to-finish barn. The barn was mechanically ventilated and used air filtration in the inlets, which were located in the attic. To evaluate the ESP performance, the filter bank in one of the ventilation boxes was replaced with the ESP setup.Â
To evaluate the ESP’s performance in capturing viruses in the field, PRRSV was aerosolized and introduced at the ESP inlet. PRRSV strain VR2332 was grown and titrated to 106.75 TCID50/mL and the suspension was spiked with a fluorescein physical tracer dye at 0.3 g/L. Two trials were performed at a temperature of 15°C (59 °F) with 47% relative humidity. The airflow rate was maintained at 1200 cfm. After collection, samples were analyzed for viable virus by titration and for viral RNA through PCR testing. Â
Results demonstrated that ESP collection efficiency was above 99% for particles greater than 1 µm. For particles less than 1 µm, collection efficiency varied by temperature, with higher efficiencies generally observed at lower temperatures.  The ESP was also highly effective at removing PRRSV with removal efficiencies higher than 99%. Â
An assessment of the on-farm feasibility of using the ESP under field conditions included a cost comparison of purchasing, installing and operating the equipment compared to those of air filtration. Other considerations included operational sustainability as well as the upkeep and maintenance of the equipment. Unlike disposable mechanical filters, ESPs operate by electrically charging and collecting particles onto plates, which must be regularly cleaned to maintain efficiency. Â
The economic analysis included assumptions on acquisition, installation, operation, maintenance and replacements costs for the ESP and filter systems. Investigators concluded that the ESP system had a $299,553 greater net present value over a 15-year period, resulting in approximately $0.25 additional cost per weaned pig, when compared to air filtration. This costing model is based on the assumptions around current technology. Future engineering advances may make this model more economically viable in the future.Â
Scalability of the ESP for on-farm use involves moving the technology from laboratory- or pilot-scale units to systems capable of handling the significant air volumes necessary for large commercial farms. This requires robust engineering solutions that maintain high efficiency of ESP while operating continuously under real-world weather and climate variability. Farms have differing building designs and adoption of the use of this technology requires innovative retrofitting solutions that do not compromise the structural integrity or operational flow of the facility. Â
Overall, the ESP tested in this study was highly effective at removing airborne particles with collection efficiencies similar and marginally superior to those of a MERV-16 filter. The path to commercialization and more broad scale use of ESP is dependent upon successfully resolving the complex logistical and engineering challenges of scalability, design integration, long-term maintenance, and cost-effectiveness for producers. Further commercial exploration is needed to fully optimize ESP designs and maintenance protocols for practical applications to improve biosecurity within commercial pig farms. Â Â
Foundation for Food & Agriculture ResearchÂ
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 US Department of 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. Connect: @FoundationFARÂ
Swine Health Information CenterÂ
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].
A study funded by the Swine Health Information Center Wean-to-Harvest Biosecurity Research Program, in partnership with the Foundation for Food & Agriculture Research and Pork Checkoff, assessed pig caretaker motivation and resources for practicing biosecurity in the wean-to-market phases of production. Led by Dr. Michael Chetta at Talent Metrics Consulting, the study revealed that greater emphasis on recognition, rewards, and resources positively influences caretakers’ biosecurity compliance. Additionally, new technologies and improved building designs were found to reduce caretaker demands while simplifying adherence to biosecurity protocols. Researchers observed that caretakers exhibit higher levels of trust when adequate resources, fair compensation, and recognition are provided. Conversely, concerns related to pay, disease threats, and equipment limitations were shown to negatively affect caretaker performance and overall work engagement.Â
Find the industry summary for Swine Health Information Center project #24-093 here.Â
Understanding what motivates farm caretakers is key to improving biosecurity. Earlier research provided support for the idea that caretakers generally want to follow biosecurity rules, but their motivation mostly came from within (personal values and beliefs) rather than from outside rewards or recognition. This previous work explored the motivations and barriers that determine whether caretakers consistently perform biosecurity control measures, and identified key drivers of motivation (Attitude strongest, Social Norms weakest), job resources which exert the greatest positive influence (Supervisor Support & Job Control) and least positive influence (Rewards), and the job demands determined to be most strongly acting as barriers which can prevent biosecurity compliance (Physical Workload & Demanding Contact with Animals). Â
Building on this previous work, the new study described herein conducted a more focused and in-depth analysis of those previously identified variables of interest. Goals and objectives of the in-depth analysis were to conclusively identify the job aspects most important to the role, as perceived by caretakers, and to communicate where pork producers’ targeted interventions would be most efficient and appropriate.Â
To conduct the analysis, a sample of 35 participants were recruited from four commercial pork producers based in the Midwest. Combined, these corporations have facilities in 11 states and three rank among the top 25 largest pork producers in the US. Data was collected between November 1, 2024, and April 1, 2025. Individuals who were actively employed caretakers in the wean-to-market phases of swine production were eligible to participate in the study. All 35 participants were invited to complete a survey questionnaire and an interview. Although only 28 individuals completed the survey, interview participation was higher (n = 35) and comprised the total sample size of 35. Â
The interviews were structured and contained five items to investigate:
1) the work caretakers do
2) their feelings on biosecurity (attitude)
3) their supervisor’s duties (supervisor support)
4) supervisor’s behaviors/actions (social norms)
5) biosecurity adherence
The survey questionnaire focused on aspects of the caretaker experience that were found in previous research as being the most influential on attitudes and behaviors related to biosecurity compliance, such as resources/support, feedback from supervisors, rewards, and the physical demands of the work. Surveys were available in both English and Spanish to accommodate participant language needs. The survey sample population included caretakers directly employed or contracted by one of the five participating pork producers (78.6%, 22/28) as well as owners (21.4%, 6/28). Â
Overall results of the quantitative analyses provide support for the idea that caretakers perceive biosecurity compliance as a high priority. Caretakers in the study often pointed out that simple mistakes, inattention, or lack of action by others were the most common reasons for breaking biosecurity protocols. Many also noted that there are very few rewards or recognition for doing things right, sometimes only punishments for getting things wrong. In other words, there is little external motivation to reinforce the importance of following biosecurity procedures. Â
Caretakers consistently confirmed that biosecurity is important and that compliance results in keeping the animals healthy. The sentiment most found while they spoke of biosecurity was trust (e.g., in supervisors, protocols, training, resources, facilities, and equipment). Job resources and support were identified as important to caretakers as they deal with the demands of their role. The physical nature of the work and continuous vigilance required to monitor animals for injury or illness may hinder their ability to consistently and correctly comply with biosecurity. The results strongly suggest that increasing caretaker resources as a potential intervention strategy could positively increase the consistent and correct execution of biosecurity protocols. Specifically, two areas identified as opportunities focused on 1) being rewarded for following biosecurity procedures, and 2) performance being rewarded properly.Â
With these outcomes, focus can more conclusively move away from training and motivation as areas of deficiency and focus on recognition, rewards, and resources to positively impact biosecurity compliance. The study reinforced that when these elements are lacking, performance and compliance can decline. Furthermore, technological upgrades and modernized facilities were viewed as crucial for reducing physical demands and simplifying biosecurity procedures. Â
With a focus on employee motivation and attitudes, this research will aid in the creation of interventions and processes to improve resources, recognition, and effective supervision that ultimately impact how caretakers do their jobs. By learning more about the challenges caretakers face and how biosecurity is impacted, the industry can better design systems that support workers, strengthen farm practices, and further protect animal health. Â
Foundation for Food & Agriculture ResearchÂ
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 US Department of 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. Connect: @FoundationFARÂ
Swine Health Information CenterÂ
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].
A new real-time, county- and farm-type stratified spatial disease surveillance system for swine pathogens has been developed to detect diseases at a regional level. The study, funded by the Swine Health Information Center, sought to evaluate a surveillance system that integrates diagnostic and animal movement data to track pathogen activity and spread at the site and regional levels. Led by Dr. Gustavo Silva at Iowa State University and his PhD Candidate Swaminathan Jayaraman, a comprehensive, data driven approach to emerging disease management was developed integrating data from 3,084 sites across 18 US states representing 10 major production systems. The newly developed system detects emerging diseases and provides weekly infection risk forecasts to support targeted disease control efforts. Producers and veterinarians who are interested in joining this surveillance system as participants should contact Dr. Silva at [email protected].Â
Find the industry summary for Swine Health Information Center project #24-029 here. Â
By integrating diagnostic data, animal movement information, and site location data across >3,000 sites, the analysis revealed critical insights into disease transmission dynamics. Results determined that farm type is the primary determinant of porcine reproductive and respiratory syndrome virus transmission risk, accounting for 81% of the total variance. Two complementary Bayesian spatial surveillance models were used to characterize PRRSV transmission dynamics at the county and sites levels. Models incorporated farm-type stratification to account for different breeding herds, growing herds and other herds in addition to spatial proximity within a 25 km radius. Â
Baseline infection probabilities for PRRSV were 73% for growing herds, 70% for breeding herds, and 58% for other herds. Movement networks were found to be the second most significant factor at 16%, with geographic proximity explaining only 3%. This finding challenges the conventional emphasis on geographic clustering and highlights the importance of production phase in disease spread.Â
Overall, the system’s forecasting capabilities achieved accuracy of over 83% for county level models and over 84% for site level models for a one-week horizon. Although predictive accuracy decreased for longer forecasting periods, the system’s ability to provide timely, actionable data remains a powerful tool for veterinarians and producers. Â
The study also documented numerous spillover events, identifying how infections likely spread between different sites and farm types, often within the same production system and within a relatively short distance. The spillover analysis (January 2019 – June 2025) documented 319 breeding herd outbreaks, of which 109 were linked to a potential spillover from other sites. Spillover events were characterized by state, farm type, distance between sites, and pathogen lineage. The system also detected site-specific events, enabling direct feedback to producers and supporting targeted outbreak investigations. Â
A conditional logistic regression model further assessed risk factors, demonstrating that increased densities of total and PRRSV-positive farms in the vicinity of breeding herds significantly raise the odds of an outbreak. This model assessed risk factors for PRRSV or PEDV classification in newly positive sites, incorporating farm density within a five-to-20-mile radii around breeding herds. Â
This surveillance system offers data-driven, actionable insights to reduce disease spread, guide targeted interventions, and improve swine herd health at both site and regional scales. By integrating diagnostic, movement, and spatial data into a single, continuously updated platform, it enables early detection of emerging health threats, identification of high-risk sites, and real-time situational awareness for veterinarians and producers. The overall findings emphasize the dominant influence of production phase and movement connectivity on PRRSV transmission, challenging the traditional focus on geographic clustering. Â
Further, findings advocate for targeted surveillance and intervention strategies tailored to farm-type risk profiles and movement networks to improve precision disease control in commercial swine populations. Ultimately, this work provides the US swine industry with a proactive tool to strengthen biosecurity, enhance disease preparedness, and protect animal health and productivity.
This month’s Domestic Swine Disease Monitoring Report highlights several key points: PRRSV activity continues to rise, with 43.67% positivity in wean-to-market sites, while sow farm positivity remains relatively low at 17.03%. The lineage L1C.5 is surging, with 3,653 detections in 2025—already surpassing last year’s total—and has become the predominant lineage over other lineages, such as L1A and L1H. IAV positivity reached 35.44% in wean-to-market, accompanied by a surprising decrease in sow farm positivity to 15.16%. Following the expected pattern for this time of the year, M. hyopneumoniae reached its highest overall positivity. A bonus page features highlights from the SDRS Advisory Group on current pathogen activity, presented during the October 2025 Winter Preparedness Call. In the podcast, Dr. Brooke Kitting, Senior Veterinarian at Seaboard Foods, discusses strategies for tackling PRRSV outbreaks and pig flow biosecurity, managing PEDV and M. hyopneumoniae outbreaks, and preparing for winter through vaccination and immunity-boosting protocols.
In this month’s Global Swine Disease Monitoring Report, details concerning the confirmation of the first case of African swine fever (ASF) in Taiwan are included, along with information on the geographical expansion of foot-and-mouth disease (FMD) in Asia, with the SAT1 serotype confirmed for the first time in Azerbaijan. Surveillance efforts at points of entry included local authorities seizing over 300 kg of untraceable meat and 75 packets of banned Chinese pork noodle products in London’s Chinatown. These findings underscore the ongoing global efforts to monitor and control the spread of swine diseases through both in-country reporting and border security.
PRRS Cumulative Incidence for MSHMP
PEDV Cumulative Incidence for MSHMP
Three PRRSV variants were classified as Variants Under Monitoring (VUMs) category 2 or higher and are described in this month’s report: Variants 1C.5.32 (VUM Category 4), 1C.2 (VUM Category 3), and 1C.5 (VUM Category 3). Variant 1C.2 was demoted from VUM Category 4 to VUM Category 3, and variants 1H.18 and 1C.5.37 were demoted from VUM Category 2 to VUM Category 1. New variant-specific situation reports were created to record these changes. Previous reports for all variants ever classified as VUM Category 2 or higher remain available.
