If images are not visible, click on Webpage version at top of newsletter

The NAHLN Update |2015| 
Volume 6, No. 1



Founding Principles and Features of the NAHLN 


  • Quality management standards
  • Competency of laboratory personnel
  • Standardized diagnostic techniques
  • Reference materials and equipment
  • Secure communications and reporting system
  • Adequate facilities to ensure biosafety/biosecurity levels
  • Assessment of preparedness through scenario testing


Quick Links



For quick viewing, click below on the articles that interest you!


In This Issue
Note from NAHLN Leadership
Hot Topics
NAHLN Laboratory Director Feature
QA Update
NAHLN Portal Update
NAHLN Working Group Updates
Getting to Know Us
VS Surveillance Update
Procedure Manual References
Acronym Key

 Events in 2015 


January 27-29

Atlanta, GA


January 28-30

Annual American Sheep Industry Association

Reno, NV

February 4-7

Cattle Industry Convention

San Antonio, TX

March 23-26

National Institute for Animal Agriculture Annual Conference

Indianapolis, IN


June 3-5

World Pork Expo

Des Moines, IA


June 15-18

17th International Symposium World Association of Veterinary Laboratory Diagnosticians

Saskatoon, Canada


July 10-14

American Veterinary Medical Association Annual conference

Boston, MA

October 22-28

119th USAHA/58th AAVLD Annual meeting

Providence, RI


October 17-21

American College of Veterinary Pathologists (ACVP)/American Society for Veterinary Clinical Pathology (ASVCP) 2015 Annual Meeting

Minneapolis, MN


December 6-8

2015 Conference of Research Workers in Animal Disease (CRWAD) Annual Meeting

Chicago, IL


Message from NAHLN Leadership  


Happy 2015!

It has been quite some time since we last published a NAHLN Newsletter and we are quite excited to welcome in a new year with an update about our 2014 activities. Thank you to our loyal readers who have offered kind words of encouragement anxiously awaiting a new edition of the newsletter! We have been very busy over the last year with a number of transitions, new opportunities, and many projects.

The NAHLN Program Office faced several staffing changes over the last few months. Our long-time budget analyst, Jill Brown, was offered a new career opportunity  outside of NAHLN and changed positions. While we miss her, she's just  upstairs so we keep in touch. Racheal Conrad took a new position outside of Federal employment but we recently welcomed Tony Nussbaum as our new Office Assistant. The Associate Coordinator position was advertised in November and we expect to have that position filled within the next few months. Meanwhile, the rest of the staff do a fantastic job maintaining NAHLN, completing projects, and tackling new initiatives.

Throughout the last year, we focused on planning and preparing for the transition to the new network structure. The NAHLN Coordinating Council has been very active in the transition planning process. A summary of the transition process and what to expect in the coming year is included in this newsletter. The Coordinating Council has also been updating the  strategic plan, which will soon be posted on our website. And, like many of you, activities supporting the Swine Enteric Coronavirus Disease testing and response efforts were a top priority for us last year.

We included updates on some of the activities of the workgroups that support NAHLN-- the Methods Technical Working Group (MTWG), the Exercises and Drills Working Group (EDWG) and the NAHLN IT Committee. The support and participation of these groups in the NAHLN is key to helping us move forward.

Not all our activities are new. The mainstays of the NAHLN Program continue to operate and improve, including the Quality Management Systems trainings conducted in collaboration with AAVLD; the NAHLN Portal; assay validation studies, and surveillance for many diseases.

We are looking forward to a very busy 2015. In addition to implementation of the network transition activities, we will be involved with VS' emerging disease and national reportable disease initiatives. We plan to continue to make improvements for electronic messaging and enhance the utility of the NAHLN Portal. Our commitment to quality management system training will continue, as will our support and management of on-going emergency response and surveillance activities.



  Sarah Tomlinson 


Sarah M. Tomlinson, DVM           



Christina M. Loiacono, DVM, PhD, DACVP 

Associate Coordinator


National Animal Health Laboratory Network



Input Welcome!

We appreciate hearing from you!   Are there other topics that you would like to hear about? 
Please e-mail your comments to us at

Current Number of Subscribers:







Hot Topics



The NAHLN Coordinating Council focused on two major activities in 2014. First, the committee updated the NAHLN Strategic Plan to reflect five strategic priorities and associated activities across the network for the next three years. The NAHLN Program Office will be developing the complementary Operational Plan next. Secondly, the Coordinating Council developed a transition plan for implementation of the NAHLN restructure, as proposed in the 2013 NAHLN Concept Paper.

The transition will occur in the following stages:

  1. Self -Assessment (Completed September 2014): Each current NAHLN laboratory will be asked to provide their assessment of which level (Level 1, Level 2, Level 3, Affiliate, or Specialty as defined by the Concept Paper), they believe their lab best fit the established criteria, based on current capabilities, resources, commitment by State, and other relevant considerations.
  2. External Review (Ongoing: September- December 2014): APHIS and NIFA will review the laboratory Self-Assessments, previous accomplishment reports, past performance, and other pertinent information to evaluate which level they potentially qualify for.
  3. Needs Evaluation (Initiated: August 2014 - January 2015): A number of factors will be considered to determine the number of laboratories needed at each level. These factors will include, but are not limited to: geography, animal distribution, commodity demographics, farm gate values, pathway/risk assessments, capacity evaluations, etc.
  4. Recommendations for Laboratory Distribution (Planned: March 2015): Based on all of the information gathered and analyses performed in Stages 1-3, APHIS and NIFA, in consultation with the NAHLN Coordinating Council will make recommendations on laboratory distribution to the VS and NIFA Deputy Administrators, with final restructuring to take effect in 2016 in accordance with USDA funding cycles.

Since its appearance in the United States in April 2013 and identification through NAHLN laboratory testing, porcine epidemic diarrhea virus (PEDv) has spread to over 30 States. In early 2014, an additional related coronavirus, porcine delta coronavirus (PDCoV), appeared in this country. These viruses are collectively referred to as swine enteric coronavirus diseases (SECD). Infections with novel SECD can cause significant morbidity and mortality, particularly in young piglets. Since April 2013, the swine producers, industry, veterinary diagnostic laboratories and Veterinary Services have been working to control the diseases.


In response to the mounting impact SECD continues to have on the U.S. pork industry, on June 5, 2014, the USDA issued a Federal Order requiring the reporting of SECD, implementation of herd monitoring, and management of Novel Swine Enteric Coronavirus Diseases. NAHLN laboratories are conducting the testing and reporting  results to the NAHLN Program Office for collation of results. Weekly laboratory testing reports were produced by the NAHLN Program Office in collaboration with the VS' Surveillance, Design and Analysis group since June 2013 and now accompany the weekly situation report. This combined report contains the field-based information entered into the Emergency Management Response System (EMRS). We've learned many lessons from SECD, and have made a number of advancements in collaborations, IT, and diagnostics across the network as a result of this outbreak.


 Laboratory Messaging

The network made significant advancements in secure communication mechanisms in the form of standardized, electronic messaging of test results. In 2013 and 2014, as a result of a close collaboration between the NAHLN Program Staff, VS' Office of the Chief Information Officer (OCIO) technical staff and the Surveillance, Design and Analysis Unit, the NAHLN IT system underwent a number of modifications and updates to increase functionality and is now known as the Laboratory Messaging Services (LMS). The LMS uses the same Health Level 7 (HL7) standards that the NAHLN IT system has used historically, but with a more general approach to accommodate messaging of any test results much more quickly. As a result, electronic messaging is now available for porcine epidemic diarrhea virus and porcine delta coronavirus, Influenza A in swine, foot and mouth disease and African Swine Fever. Input, user acceptance testing, and feedback from the NAHLN IT Committee has been essential. Furthermore, LMS has now been integrated with VS' Emergency Management Response System (EMRS 2.0) with the functionality operational in SECD reporting. Through this integration, we closed a long-identified gap for electronically integrating laboratory test results with field outbreak investigation data..


Collaborative inter-laboratory comparison and negative cohort studies are a routine NAHLN function as a part of diagnostic assay validation. Overall, these studies provide data needed to determine if and how the assays should be used for a specific purpose (fit for purpose) and how the assay performs on the U.S.' negative population. Inter-laboratory comparison studies provide data about reproducibility and robustness of assay, while negative cohort studies provide specificity parameters and identify cross reactivity with other agents. The studies are designed to meet OIE guidelines for sample size numbers and geographic distribution representative of US livestock populations. The process for implementing these studies includes open communication with the stakeholders and approval by each participating State's Animal Health Official. This year, 13 NAHLN laboratories participated in inter-laboratory comparisons and negative cohorts for two different FMD serologic ELISAs. These studies were collaborations with NVSL's Foreign Animal Diagnostic Disease Laboratory and the Institute for Infectious Animal Diseases (IIAD). The statistical analysis is near completion and the dossier is being prepared for review by the MTWG in early 2015. In addition, five NAHLN laboratories participated in an inter-laboratory comparison and negative cohort study for an influenza A H5/H7 RT-PCR. Results will be presented in early 2015. The dossiers for the FMD milk PCR and FMD penside assays were also completed and reviewed by the MTWG for their recommendations to VS on the use of the assay.


Adding aquatic animal testing to the NAHLN will enable VS to build our nation's capacity for accessible, timely, accurate, and consistent aquatic animal disease laboratory services. The NAHLN system will provide a framework for standards, including an implemented quality management system and adherence to standard operating procedures (SOPs). The goal is that through NAHLN, standardized reliable testing for targeted surveillance will be used for baseline and zonation studies (disease freedom); for monitoring of high-consequence aquatic diseases (of regulatory or industry concern); for responding to disease outbreaks; and for interstate and international movement and trade. Implementation will move forward in three phases. Phase 1 is underway.

Phase 1

NAHLN Methods Technical Working Group (MTWG) reviewed and approved the SOPs for infectious salmon anemia virus (ISAv) and viral hemorrhagic septicemia virus (VHSv) testing. Existing NAHLN laboratories were invited to choose to participate in Phase 1 by including ISAv and VHSv in their NAHLN testing capabilities, taking part in proficiency testing and reporting results as indicated in the SOPs. A total of 14 NAHLN laboratories are approved to test, with proficiency testing to begin in early 2015.

Phase 2

Federal and State non-NAHLN laboratories (e.g., U.S. Fish and Wildlife Fish Health Laboratories) and private aquatic animal health testing laboratories will be invited to consider applying for NAHLN approval and test for the approved aquatic diseases using standardized requirements. This phase will be implemented when the new Specialty laboratory category is implemented during the NAHLN Structure.

Phase 3

Additional aquatic animal pathogens identified by the Aquatic Animal Health Program in consultation with the Subcommittee on Aquatic Animal Health (SAAH), National Import Export Services (NIES), and NVSL will be added to the NAHLN disease testing list. The NAHLN Coordinating Council will evaluate and approve these prior to being added to the aquatic animal pathogen group within the NAHLN scope. The NAHLN MTWG will review the associated SOP.

Article submitted by Christina M. Loiacono, DVM, PhD, DACVP, Associate Coordinator, NAHLN Program Office,  USDA APHIS VS STAS NVSL, Ames, IA and Sarah M. Tomlinson, DVM, NAHLN Coordinator, USDA APHIS VS STAS NVSL, Fort Collins, CO



NAHLN Laboratory Director Feature

Featured NAHLN Laboratory Director:   

Jane Christopher-Hennings DVM, MS


Academic/Laboratory Background:               

Dr. Jane Christopher-Hennings Laboratory Director South Dakota Animal Disease Research and Diagnostic Laboratory  

Dr. Christopher-Hennings received her BS Degree at the University of Wisconsin-Madison, DVM at University of Minnesota in 1983 and then was in private veterinary practice for 6 years in South Dakota. She then went back to school for her MS Degree at the University of Wisconsin-Madison and subsequently worked as a Post-doctoral Researcher at South Dakota State University. In 1996, Dr. Christopher-Hennings became a full-time tenure track Faculty member at South Dakota State University (SDSU) within the Veterinary and Biomedical Sciences Department. In fall 2013, she became the Director of the Animal Disease Research and Diagnostic Laboratory (SD ADRDL) and Head of the Veterinary and Biomedical Sciences Department after a national search.


 Is there anything unique in your career that you'd like to share?

"I have worked with a number of different species of animals, including primates, at the University of Wisconsin-Madison for my MS Degree. I was also in small animal and equine practice in South Dakota and now have been working with swine for over 23 years. I enjoy the variety and really like to discover and do "new" things. Research is exciting since it is great to discover and investigate new findings. My job is important at this time to facilitate the research of new scientists and diagnosticians."


How long have you been Director?

1 year and 3 months


What brought you to a NAHLN Laboratory?

"I came to the laboratory in 1990, prior to NAHLN being formed. My husband had been accepted into Pharmacy School at South Dakota State University, so I moved with him and started working in the laboratory in a post-doctoral position at the SDSU Veterinary & Biomedical Sciences Department. My research started with studying Shiga-like toxins in E. coli in pigs and I was in charge of the gnotobiotic facility at SDSU. Since Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) was just discovered at that time and since it was unknown whether PRRSV was transmitted through boar semen, my project focused on developing a PCR based assay for detection of PRRSV in boar semen and determining the pathogenesis of PRRSV in boars. Through the development of this PCR based assay and 2nd generation real-time PCR assay which was then commercialized, I started the Molecular Diagnostic Section at South Dakota State University. We are now performing over 100,000 PCR based tests within this section. I was the Section Head in Clinical Pathology until 1996 and Molecular Diagnostics from its inception in the early 1990s up to today."


Do you have any hobbies that you'd like to share with us?

"I like to read (eg. biographies), jog, redo my house in the country (or at least have ideas on how to do this and have someone else actually do the work).  I enjoy music and dance (Latin dances and others as well)."


Lastly, why is NAHLN important to you?

"The colleagues, collaborations and good communications within the NAHLN are essential and all of these aspects have made working within NAHLN very rewarding. I appreciate the support between laboratories that is conducive to solving and controlling infectious disease issues in animals and for public health purposes. I just want to say "thank you" for the supportive culture that currently exists in NAHLN. I also appreciate NAHLN in reaching out and communicating with the various stakeholders, livestock commodity groups and clients that we serve within our laboratories."


Welcome to the NAHLN, Dr. Christopher-Hennings!


Article submitted by Traci Imlau, Program Assistant, NAHLN Program Office, USDA APHIS VS STAS NVSL, Ames, IA


QA Update


Quality Management System Training 

In 2010, the original Quality Management System (QMS) course was developed to assist the NAHLN laboratories in implementing and continually improving quality management systems. It has since expanded to assist other laboratory networks and international colleagues. In April 2014, the NAHLN Program Office and AAVLD trainers provided QMS training to the Plant Protection and Quarantine's (PPQ) Center for Plant Health, Science and Technology (CPHST) Laboratory in Beltsville, MD in support of the National Plant Diagnostic Network (NPDN). In August 2014, the NAHLN Program Office along with International Services (IS), Veterinary Services' Professional Development Staff (PDS), and AAVLD trainers collaborated to offer the annual QMS training course in Ames, IA. Forty-five participants from NAHLN laboratories and 21 participants representing 16 countries participated in the QMS training. The three-and-a-half day training provided an interactive class environment that included topics such as: quality management system requirements, document control, internal auditing, corrective actions, root cause analysis, and a mock audit. In 2015, there will be two QMS trainings provided: one in January presented to representatives of the NPDN. In August of 2015, NAHLN will again work with IS and PDS to provide QMS training to NAHLN laboratory staff and international participants. Additionally, the development and expanded use of the on-line QMS training -- a collaboration between AAVLD, Washington Animal Disease Diagnostic Laboratory and NAHLN-which continued in 2014 and will be on-going this year.


 Article submitted by Christina Loiacono, DVM, PhD, DACVP, Associate Coordinator, NAHLN Program Office,  USDA APHIS VS STAS NVSL, Ames, IA


NAHLN  Portal Update


The NAHLN Portal provides NAHLN laboratories a web-based mechanism to input and update their NAHLN-related information, resulting in more efficient communication with the NAHLN Program Staff and timely sharing of ideas and information through the various NAHLN work groups. Updates that were completed in 2014 include expanding and refining the functionality of the NAHLN laboratory directory. This resulted in mechanisms for receiving invitations to participate; registering participants and entering test results for proficiency tests (PT); accessing current standard operating procedures; providing electronic copies of accreditation documents and a means for monitoring assay performance. Phase one of the enhancement and expansion of the core functionality in the PT section has been completed. This included non-NAHLN, APHIS-approved PTs. Phase two, which is the addition of laboratories and personnel associated with non-NAHLN, APHIS-approved testing into the lab directory, is expected to be completed by early 2015. Phase three is expected to be completed by mid-2015 and will allow labs to receive non-NAHLN, APHIS-approved PT invitations, register participants and enter PT results using online forms. Additionally in 2014, the NAHLN Portal was integrated with the Laboratory Capacity Estimation Model (LCEM) eliminating the need for double entry of some information fields related to laboratory capacity that now automatically move into LCEM from the Portal.


Article submitted by Cindy Chard-Bergstrom, Microbiologist, NAHLN Program Office, USDA APHIS VS STAS NVSL, Ames, IA

NAHLN Working Group Updates


NAHLN Methods Technical Working Group


The NAHLN Methods Technical Working Group (MTWG) finalized the methods comparison process and continued to detail the De Novo development and validation processes, including the specific criteria for validation of multiplex assays. The group met in April 2014 to discuss- technical approaches to emerging diseases and review a proposal for multiplex assay development and several other topics. The dossier for real time RT-PCR for Foot and Mouth Disease (FMD) virus in bulk tank milk was presented and reviewed as well. The dossier for the FMD pen-side antigen assay was also completed and reviewed in 2014. Upcoming dossiers for review include the real time RT-PCRs for Lumpy Skin Disease and Contagious Bovine Pleuropneumonia, and two FMD serological negative cohort studies. Additionally, the group reviewed and provided input on a number of NVSL Standard Operating Procedures for NAHLN assays, held discussions with the National Poultry Improvement Plan (NPIP) to understand program requirement differences, and provided input on SECD panel development and next steps for standardization. Finally, discussions continued regarding the network's role and technical contributions in emerging disease detection, including development of questions to ask laboratories about their emerging disease detection capabilities.

NAHLN Exercises and Drills Working Group

The NAHLN Exercises and Drills Working Group (EDWG) provided and/or sponsored informational webinars on relevant topics such as Respiratory PPE used in laboratories and an Overview of Biosafety and Biosecurity in NAHLN Laboratories. The EDWG developed an FMD table-top exercise to target the receiving and accessioning sections of laboratories and provided this to the FMD-approved NAHLN laboratories to complete in late 2014. Responses to this table-top exercise are currently being analyzed to provide feedback to laboratories, as well as to direct development of future exercises. One such exercise is a hands-on receiving/accessioning exercise that will occur in the first quarter of 2015. Ten NAHLN laboratories that participated in the FMD table-top exercise will receive increments of increasing numbers of mock-samples in their laboratories to process through the receiving and accessioning sections over a three day period. Additionally, the EDWG is working towards an exercise program that includes regular drills, exercises targeting specific areas and processes in labs, and utilization of virtual tools such as LCEM and the NAHLN Portal to train and overall enhance preparedness in laboratories.


Article submitted by Christina M. Loiacono, DVM, PhD, DACVP, Associate Coordinator, NAHLN Program Office,  USDA APHIS VS STAS NVSL, Ames, IA and Sarah M. Tomlinson, DVM, NAHLN Coordinator, USDA APHIS VS STAS NVSL, Fort Collins, CO



Getting to Know Us - Kelly Burkhart - Volume 6, No. 1



Kelly Burkhart joined the NAHLN Program Staff as a Microbiologist in 2007. Kelly received a degree in Microbiology from Iowa State University. Prior to joining NAHLN, she spent 12 years in industry as a research scientist with Beohringer Ingelheim Vetmedica. Her primary focus was Porcine Reproductive and Respiratory virus, and was responsible for clinical development to help determine suitable vaccine candidates.

Kelly Burkhart, Microbiologist, National Animal Health Laboratory Network


Since starting with the NAHLN, Kelly has been responsible for quality assurance within the network. Kelly works with the laboratories on the annual NAHLN Qualification Checklist, Quality Management System trainings and quality audits.

Kelly enjoys spending time with her husband, Bret, and two children, Hannah age 15 and Jessica age 12. Their two beautiful daughters are very active, which keeps her very active! In her spare time she appreciates time spent reading and doing cross-stitch. They also share their household with two cats, Ollie and Charlie. 

Regarding thoughts on the NAHLN program/mission, Kelly states: "I think that we hear many examples of why preparedness is so important, whether in regards to human or animal disease. While no laboratory is ever completely prepared, NAHLN helps by providing our laboratories with the structure and mechanisms to increase their level of readiness. It has been amazing to see the network grow and develop to what it is today. I feel blessed to be a part of this amazing organization, and to have the opportunity to interact with so many wonderful people!"

Thank you, Kelly, for your tremendous impact to the NAHLN mission and helping us continue to safeguard animal health.


Article submitted by Traci Imlau, Program Assistant, NAHLN Program Office, USDA APHIS VS STAS NVSL, Ames, IA



NAHLN Surveillance Update


The NAHLN continues to collaborate with other groups in APHIS, such as the NVSL reference laboratories, Wildlife Services, Surveillance, Design and Analysis Unit, the Surveillance Response and Preparedness Services Unit to design and implement surveillance programs in domestic and feral species. In fiscal year 2014, NAHLN laboratories participated in APHIS surveillance programs for bovine spongiform encephalopathy (BSE), classical swine fever (CSF), scrapie, influenza A virus in swine

(IAV-S), and pseudorabies virus (PRV).


NAHLN laboratories play a critical role in VS surveillance programs by providing rapid standardized testing and results reporting for the above-mentioned diseases that are targeted in national animal disease surveillance initiatives.

Testing data provided in The NAHLN Update are based on results data that are available at the time of release of the newsletter. Testing numbers may change in future reports as new information is received and testing data are updated (for reference, see article in Volume 3, No. 2 edition titled, "Data dynamics within the SIV Surveillance Program, Why do the reports change?").


BSEBovine Spongiform Encephalopathy (BSE) Surveillance


The USDA has conducted surveillance for BSE since 1990. In 2004, following the December 2003 detection of BSE in an imported cow, USDA implemented an enhanced BSE surveillance program to more accurately determine the prevalence of the disease in the U.S. cattle population.


USDA concluded that the prevalence of BSE in the United States is extremely low (less than 1 case per million adult cattle), and in 2006, transitioned to an ongoing BSE surveillance program that tests at a level more commensurate with this extremely low level of risk. Ongoing BSE surveillance exceeds guidelines set forth by the World Organization for Animal Health (OIE), providing testing at a level 10 times that which is recommended by OIE.


On May 29, 2013, Agriculture Secretary Tom Vilsack released a statement regarding notification received from the World Organization for Animal Health (OIE) upgrading the United States' risk classification for bovine spongiform encephalopathy (BSE) to negligible risk. This was a significant achievement and it demonstrates OIE's belief that both our surveillance for, and safeguards against, BSE are strong.


The NAHLN laboratories have provided BSE surveillance testing since 2004. Currently, six NAHLN laboratories provide diagnostic testing for the BSE surveillance program. These laboratories continue to conduct testing to detect BSE at the very low level of less than 1 case per million adult cattle, assess any change in the BSE status of U.S. cattle, and identify any rise in BSE prevalence in this country. The NVSL Pathobiology Laboratory in Ames, Iowa, serves as the national reference laboratory and performs surveillance and confirmatory testing on all samples identified as suspect (potential positive) for BSE by the NAHLN laboratories.


The chart below shows sample testing performed, by quarter, for BSE by NAHLN laboratories (not including NVSL) in Federal fiscal years (FY) 2013 and 2014. The total number of animals tested for BSE by NAHLN laboratories in FY 2013 (October 2012 through September 2013) was 40,699 and in FY2014, 38,936 animals were tested (not including NVSL).





CSFClassical Swine Fever Surveillance 


The CSF surveillance program was initiated in 2006 to rapidly detect CSF virus and monitor the risk of introduction of the virus in the U.S. swine herd. The surveillance program targets five specific swine populations for testing:

  • Sick pig submissions to veterinary diagnostic laboratories (VDLs)
  • Slaughter swine with a high probability for CSF exposure
  • Feral swine
  • Swine populations (including waste feeding operations) with a high probability for CSF exposure in Florida, Texas, and Puerto Rico
  • Swine highly suspicious for CSF and entered into a Foreign Animal Disease Investigation

NAHLN laboratories conduct CSF surveillance testing and NVSL's Foreign Animal Disease Diagnostic Laboratory (FADDL) is the CSF reference and confirmatory laboratory. In FY 2014, 15 NAHLN laboratories provided diagnostic testing for the CSF surveillance program.


The table below shows the number of animals tested for CSF by NAHLN laboratories in two target surveillance populations in FY 2013 and the first three quarters of FY 2014. Feral swine test counts are not included here and waste feeder/high probability for exposure data is not available.




SCRAPIEScrapie Surveillance

USDA initiated the National Accelerated Scrapie Eradication Program in 2001 with the goal of eradicating scrapie from the U.S. sheep and goat populations. Since 2003, surveillance for the program has been conducted primarily through the Regulatory Scrapie Slaughter Surveillance (RSSS) program, which targets sheep and goat populations that have been recognized as having higher than average scrapie prevalence.


Other scrapie surveillance also targets scrapie-exposed and potentially exposed sheep and goats found through investigations of infected animals; clinical-suspect animals and other mature sheep and goats submitted to veterinary diagnostic laboratories; rabies-suspect animals that test negative for rabies; and voluntary on-farm testing of flocks with risk factors for scrapie or as part of the Scrapie Flock Certification Program.


Currently, 17 NAHLN laboratories are approved to conduct diagnostic testing for scrapie surveillance. The NVSL Pathobiology Laboratory in Ames, Iowa serves as the national reference laboratory and performs surveillance and confirmatory testing on all samples identified as suspect (potential positive) by the NAHLN laboratories.


In FY 2013, 42,342 animals were tested, and in FY2014, 45,670 animals were tested by NAHLN laboratories for scrapie. The charts below show the number of animals, by quarter, tested for scrapie by the NAHLN laboratories in FY 2013 and FY 2014 (not including NVSL).





SIVInfluenza A Virus in Swine Surveillance

The goals of the IAV-S surveillance program are (1) to monitor the genetic evolution of endemic swine influenza A virus to better understand endemic and emerging influenza virus ecology, (2) make IAV-S isolates and associated epidemiologic data available for research and analysis, and (3) select proper isolates for the development of relevant diagnostic reagents, updating diagnostic assays, and vaccine seed stock products. The program was initiated in May 2009 with a focus on monitoring the pandemic H1N1 2009 [pH1N1 (2009)] virus in swine. As the human health threat of pH1N1 (2009) declined in 2010, IAV-S surveillance efforts were re-focused on monitoring all current circulating IAV in swine. Also in 2010, an anonymous submission protocol was adopted to encourage more industry participation and increase the number of samples available for monitoring IAV-S in the U.S. swine herd. The IAV-S surveillance efforts are targeted towards these three swine populations:

  • Case-compatible sick pig submissions to VDLs
  • Swine exhibiting influenza-like illness at first points of concentration or commingling events i.e., markets, fairs
  • Swine populations that are epidemiologically linked to confirmed human cases involving IAV-S.

NAHLN laboratories conduct IAV-S surveillance for the above-mentioned streams. The NVSL Diagnostic Virology Laboratory in Ames, Iowa is the IAV-S confirmatory laboratory.



IAV-S testing results reported by NAHLN laboratories

in FY 2013 and FY 2014

The table below shows the number of accessions tested, number of influenza-positive accessions, and number of accessions with virus subtyping results reported in FY 2013 and the first three quarters of FY 2014.

  *Influenza-positive accessions are those with samples with positive matrix assay results



PRVPseudorabies Virus Surveillance

The PRV surveillance program was initiated in 2009 as an extension of USDA's successful PRV eradication efforts. The program gathers surveillance data to support three specific objectives: (1) rapidly detect PRV entry and infection in U.S. commercial swine, (2) demonstrate freedom from PRV in commercial herds, and (3) monitor domestic sources of PRV.


Targeted Populations (surveillance streams)

  • Investigation and diagnosis of suspicious PRV cases
  • Sick pig submissions to veterinary diagnostic laboratories (VDLs)
  • Herds participating in routine serology and herd profiling
  • Herds classified as high probability for exposure
  • Herds with reported exposure to feral swine
  • Cull sow-boars at slaughter
  • Market swine at slaughter
  • Feral swine

PRV-approved NAHLN laboratories test serologic samples from domestic swine for four targeted PRV surveillance populations: sick pig submissions, routine serology and herd profiling, swine populations with a high probability for exposure, and swine with known feral swine exposure. NAHLN laboratories also conduct PRV testing for domestic swine samples that are submitted as part of epidemiologic trace back investigations. Fourteen NAHLN laboratories currently conduct PRV surveillance sample testing in domestic swine. The NVSL Diagnostic Virology Laboratory serves as the national reference laboratory and performs confirmatory testing for suspect and positive submissions for PRV.


In FY 2013, 274,252 swine were tested under the PRV surveillance program in the following streams: diagnostic laboratory serologic submissions, sow-boar slaughter, and market slaughter. NAHLN laboratories tested 23,598 swine for the PRV diagnostic laboratory stream in FY 2013 and 25,360 swine in the first three quarters of FY 2014.



The surveillance information in this article has been provided by the responsible USDA APHIS offices.
Charts in this article are based on information and test results available at the time of report generation.  Numbers are subject to change due to later reporting of test results and updates in the database(s).
NAHLN Procedure Manual References


Below you will find various NAHLN Procedure Manuals, the date of the latest version, and either a weblink or contact where they are available:


Classical Swine Fever Surveillance Procedure Manual, latest version dated April 2007


Pseudorabies Surveillance Procedure Manual, Version 1.3, latest version dated October 2010


Procedure Manual for Vesicular Stomatitis Viruses (VSV), latest version dated January 2008


Influenza Surveillance in Swine Procedures Manual, latest version dated July 2010




Archived issues of  The NAHLN Update.

The following links show a map and laboratory list of the laboratories that have been approved as part of the NAHLN testing network (including NVSL):

AI Testing Laboratories:  Map and Laboratory List
ASF Testing Laboratories: Map and Laboratory List
BSE Testing Laboratories:  Map and Laboratory List
CWD/Scrapie IHC Testing Laboratories:  Map and Laboratory List
CWD ELISA Testing Laboratories:  Map and Laboratory List
CSF Testing Laboratories:  Map and Laboratory List
FMD Testing Laboratories:  Map and Laboratory List
NDV Testing Laboratories:  Map and Laboratory List
PRV Testing Laboratories:  Map and Laboratory List
IAV-S Testing Laboratories:  Map and Laboratory List
VSV Testing Laboratories:  Map and Laboratory List 

Original 12 NAHLN Laboratories:  Map and Laboratory List

For more information on the NAHLN, visit the NAHLN Homepage

Acronym Key

Click Here for Volume 6, No. 1 Acronym Key 


Join Our Mailing List!

If images are not visible, click on Webpage version at top of newsletter