What is One Health?

One Health is the idea that human health is entwined with the health of animals and the environment. Historically, these three areas have been treated separately, resulting in distinct academic research and degree programs, professional paths and government funding streams. Yet in a world where people, food, animals and infectious diseases circulate rapidly, these divisions limit our ability to identify and mitigate community health risks.

Connecting Human + Animal + Environmental Health

The One Health concept gives a name to the reality that the next public health crisis could be caused by an avian influenza that jumps to humans or by drinking water supplies contaminated by run-off from a nearby farm.

Pathogens of zoonotic origin are the root of approximately 70-75% of the emerging infectious diseases in humans. As we develop new land, humans make novel contact with displaced animals and organisms, increasing exposure to zoonotic disease.

With climate change, arboviruses will flourish, affecting greater numbers of people and animals, and extending into new territories. The changing climate also means that the world’s farmers are likely to use more pesticides on crops to combat increasing numbers of pests.

Food issues, including the safety of any new pesticides, the use of antibiotics or other medications in food animals, or the origin of a foodborne illness, is a shared concern among environmental, human and animal health scientists.

As our world grows smaller through increased travel and trade, it is increasingly important to acknowledge the complexity of potential public health issues and to marshal our best resources by working in tandem with scientists from all backgrounds.

Public Health Labs: Crossing Spheres of Health 

Public health laboratories conduct testing that crosses among the spheres of human, animal and environmental health.

Their scientists have academic and professional backgrounds as diverse as the public health testing offered in their laboratories. This diversity allows a public health laboratory from a coastal state to test shellfish for biotoxins while a western public health laboratory tests milk to ensure safe products are reaching consumers. In some states, animal diagnostic labs are linked with public health laboratory programs. Some public health laboratories are part of a state university system that includes veterinary diagnostic labs. In all instances, these institutions are working to break down the silos that screen interrelated programs from each other.

Food Safety

Public health laboratories, with FDA funding, are helping with the accreditation of food testing and animal feed laboratories. Accreditation creates stronger labs with better data and a more robust public health laboratory system.

Public health laboratories have long worked to protect people from foodborne illness through the PulseNet program and FERN, the Food Emergency Response Network.

Foodborne pathogens are often zoonotic. An example is STEC, or Shiga Toxin-producing Escherichia coli, which originates in cows. Foodborne outbreaks can also be caused by a combination of animal and environmental conditions, such as the 2006 E. coli outbreak. In this case, spinach that had been contaminated by run-off from nearby cattle farms was removed from grocery stores across the United States.

Teams from human, animal and environmental backgrounds work together to solve foodborne outbreaks and prevent future occurrences.

Environmental Health

A public health laboratory’s environmental health program works with laboratories that conduct essential testing on drinking and surface water, air and soil. It also supports laboratories that protect our environment from natural or man-made threats.

Such a program might test for nitrate and phosphate to see if run-off from a farm impacts drinking water supplies. Just as farming practices affect human and environmental health, the health of the animal population near drinking water supplies can affect human health. Animals drink and pollute water, potentially with pathogens such as E. coli.

Infectious Disease

Public health laboratories prepare tirelessly to protect people from emerging infectious diseases. These diseases often originate from animal populations.

Humans come into regular contact with potentially contagious animal diseases. People have been infected with swine flu at state fairs, with leptospirosis from their dogs, hantavirus from contact with rodent droppings and arboviruses through mosquito bites. Surveillance and laboratory testing programs can help determine the risk to a community.

Since animal illness can easily become the next human illness, it is important for public health laboratories to stay abreast of animal and environmental conditions to keep us safe.

Other Resources

CDC One Health Office
One Health Initiative