As part of a strategic, targeted approach to control and prevent zoonotic diseases, the One Health Office at the Centers for Disease Control and Prevention (CDC) has been hosting One Health Zoonotic Disease Prioritization Workshops in several countries since 2014. A primary outcome of these workshops is to help countries focus limited resources on those zoonoses of greatest concern. Globally, zoonoses commonly prioritized include zoonotic influenza viruses, anthrax, rabies, Rift Valley fever, and viral hemorrhagic fevers, including Ebola.
A critical and first step in these workshops, as well as any One Health activity, is to identify key stakeholders to address the issue from a multisectoral approach, involving human, animal, and environmental health professionals. During December 2017, several departments within the Department of Health and Human Services, the United States Department of Agriculture (USDA), the United States Department of the Interior, the Environmental Protection Agency, the National Oceanic and Atmospheric Association, and state animal and human health agencies collaborated during a workshop focused on identifying the top zoonoses threatening public health in the United States.
Working together to prioritize zoonoses of national concern for the first time, multiple US government agency participants used a One Health approach and the One Health Zoonotic Disease Prioritization tool developed by CDC to identify 8 zoonoses that should be jointly addressed by human, animal, and environmental health sectors.
The workshop report, published earlier this year, describes the process of prioritization, the most concerning zoonoses, and discussions and recommendations on how to develop a coordinated US-specific One Health approach to prevent, detect, and respond to those zoonoses.
Prioritized zoonotic diseases for the United States
- Zoonotic influenza (zoonotic influenza A viruses)
- Salmonellosis (Salmonella species)
- West Nile virus (Flaviviridae, Flavivirus)
- Plague (Yersinia pestis)
- Emerging coronaviruses (Coronaviridae; ie, severe acute respiratory syndrome and Middle East respiratory syndrome)
- Rabies (Rhabdoviridae, Lyssavirus)
- Brucellosis (Brucella species)
- Lyme disease (Borrelia burgdorferi)
The disease ranked as the highest priority by all workshop participants was zoonotic influenza A. Swine veterinarians play a significant role in preventing zoonotic influenza.
Influenza A viruses are endemic in the US swine herd. Although rare, some strains of influenza A viruses of avian and swine origin are zoonotic and might infect people. Influenza A viruses of swine (IAV-S) origin are called variant viruses when they infect people and the letter “v” is attached to the influenza strain name (eg, H3N2v).
Of the 462 novel influenza A infections detected in the United States since 2011, 427 were H3N2v. Others of swine origin included H1N1v (9) and H1N2v (25). During late 2016, a veterinarian was infected with avian lineage influenza (H7N2) after prolonged close contact with respiratory secretions of infected cats in a New York City shelter. These novel influenza A cases were all sporadic infections with limited human to human transmission. The people with the highest risk of being infected by a zoonotic influenza virus are those in close contact with infected swine or poultry.
The CDC recommends that every person aged 6 months or older receive an influenza vaccine each year. The CDC also recommends that people who work with swine should be trained to recognize the signs of influenza in pigs. If pigs exhibit signs consistent with influenza, even mildly, appropriate veterinary care should be provided, and preventive measures should be implemented by people working with or in close contact with ill pigs. The USDA’s Veterinary Services’ national IAV-S surveillance program monitors isolates from pigs exhibiting influenza-like illness for any genetic changes. 
Opportunities for swine veterinarians
Participants from all agencies identified the following key themes and next steps for collaboration:
- Increase and leverage leadership engagement
- Create a formalized One Health coordination mechanism at the federal level
- Develop a national One Health framework
- Improve knowledge and data sharing for laboratory, surveillance, and response activities
- Improve coordination during an outbreak response
- Strengthen joint investment for One Health and prioritized zoonoses
- Provide education and awareness
- Discuss One Health research gaps and needs
While we can certainly play a role in each of these next steps (eg, increased laboratory data sharing for surveillance), two of these identified opportunities most directly involve swine veterinarians.
Improved coordination during an outbreak response. The driver of a One Health approach is multisectoral collaboration. Successful One Health responses include veterinarians, physicians, nurses, epidemiologists, diagnosticians, social and behavioral scientists, toxicologists, economists, entomologists, and many others. Even outbreaks of animal diseases that are not zoonotic (eg, African swine fever) require a One Health approach because of the intricate relationship with humans (eg, producer and responder mental health) and the environment (eg, wildlife and disposal).
Standardized multiagency outbreak response plans will improve collaborative response, while combined cross-disciplinary training (eg, tabletop exercises and field epidemiology courses) for all sectors will strengthen responder preparedness. To ensure the best outcome for people, pigs, and the environment, it is essential to have those who understand animal agriculture involved in a One Health response.
Education and awareness. Continuing education in One Health will bolster workforce development, ensuring the right people are participating in zoonotic disease prevention, detection, control, and response.
The American Association of Swine Veterinarians (AASV), Swine Health Information Center, National Pork Board, and National Pork Producers Council have a strong history of coordinated messaging to various audiences, including the general public. We routinely work together to disseminate accurate and timely information. Opportunities exist to more closely collaborate with local, state, and federal colleagues in public health to provide coordinated messaging before, during, and after zoonotic disease outbreaks or other One Health events or issues. The AASV will continue to build and strengthen these relationships.
The swine veterinarian’s role
These zoonoses were prioritized because of their pandemic/epidemic potential; the severity of disease in humans, domestic animals, and wildlife; the economic impact to the United States; the potential for introduction or increased transmission in the United States; and the bioterrorism threat to national security. Swine veterinarians in practice, industry, academia, and government can prepare producers, strengthen relationships, and coordinate messaging to prevent, detect, and control zoonotic influenza.
Abbey Canon, DVM, MPH, DACVPM
Director of Communications