A "One Health" Approach to Influenza Emphasizes Zoonotic Transmission

In the August issue of Emerging Infectious Diseases, experts Thomas F. Powdrill, Terry L. Nipp, and Jennifer L. Rinderknecht of Texas A&M University, describe the "One Health" concept, defined as "the realization that human, animal, and environmental health are interrelated." Applying this One Health approach to high-consequence zoonotic diseases is imperative, the authors assert, emphasizing that "Although pandemic (H1N1) 2009 virus has primarily affected humans (with some documented human-to-animal transmission), the genesis of this circulating human virus involved reassortment of viral genomic segments from human, porcine, and avian influenza virus lineages."

Powdrill, et al. (2010) explain that a task force of experts on influenza, public health and animal health met at the conference, One Health Approach to Influenza: Assessment of Critical Issues and Options, in Washington, D.C. in December 2009, to discuss the role of the One Health approach in preparing for and responding to an influenza pandemic or other emerging zoonotic disease by using pandemic (H1N1) 2009 as a case study. The meeting was convened by the Department of Homeland Security National Center for Foreign Animal and Zoonotic Disease Defense, and the National Institute of Allergy and Infectious Diseases/National Institutes of Health Western Regional Center of Excellence for Biodefense and Emerging Infectious Diseases.

The task force examined epidemiology and surveillance; transmission dynamics; immunobiology and vaccines; and molecular approaches and pathobiology, and, according to Powdrill, et al. (2010), made a number of conclusions:

-- Current surveillance capabilities should be expanded and improved in a scientifically rational and sustainable fashion. The task force said that this enhanced surveillance could be accomplished through the establishment of new field investigational programs and bolstering existing national and global surveillance networks, especially at the animal/human interface.

-- The measurement, understanding, and transmission control of influenza viruses between and among species and the environment is one of the most difficult topics to address. The task force concluded that new genetic markers must be identified in virus and host to clarify and potentially interrupt the transmission process.

-- One of the largest gaps found in preparedness for pandemic (H1N1) 2009 was the inability of scientists to translate virus detection and characterization into effective vaccines in an efficient and timely manner. The task force believes that the most effective way to combat these challenges is by improving vaccine technology and production, including transitioning from using the outdated technique of growing vaccine in eggs to using cell culture and reverse genetic technologies.

-- Understanding underlying mechanisms at the molecular level is critical. The task force concluded that new methods must be used to predict, prepare for, prevent and mitigate the future emergence of high-consequence influenza or other zoonotic diseases.

Powdrill, et al. (2010), write, "Perhaps the biggest challenge was in preparing for the unpredictable. It is impossible to determine specifically where and when the next influenza pandemic will emerge or its severity. Despite these unknowns, we can prepare for an influenza pandemic or another zoonotic disease through enhanced surveillance and extensive response planning. Pandemic (H1N1) 2009 was a test case for future pandemics. The challenge now will be to truly implement a One Health approach in addressing the knowledge gap in preparing for and responding to future influenza pandemics or zoonotic diseases."

Reference: Powdrill TF, Nipp TL, and Rinderknecht JL. Conference Summary: One Health Approach to Influenza: Assessment of Critical Issues and Options. Emerg Infect Dis. Vol. 16, No. 8. August 2010.

A copy of the full report may be accessed at http://fazd.tamu.edu/ITFreport.pdf.