Regardless of how the COVID-19 pandemic began, it’s clear that deadly diseases can jump from animals to humans. A new report from Harvard Law School and New York University finds that we’re not doing enough to prevent another animal-borne virus from becoming the next global pandemic.
The study, which examined common forms of animal-human interactions in 15 countries, including the United States, found dozens of examples where viruses could make the jump. The researchers suggested that simple policy changes could dramatically reduce the risk of such diseases being transmitted.
So far, too much emphasis has been placed on limiting damage after a pathogen has already jumped from animals and started spreading among humans, as Ebola did in 2014, SARS-CoV-2 did in late 2019 and what bird flu threatens to do, said Ann Linder, the report’s lead author.
But pathogens are incredibly small — 10,000 times smaller than a pinhead, she explained — and can be extremely contagious. “By the time you realize something is happening, the outbreak may have metastasized to the point where it can no longer be contained.”
Instead, said Linder, associate director of policy and research at Harvard Law School’s Animal Law and Policy Program, “we really need to shift our thinking and focus on prevention policies. We can’t hunt down these outbreaks after the fact.”
That’s why she and her colleagues have spent the last four years looking for weak spots, areas of interaction between animals and humans where viruses could potentially jump from one to the other. Unfortunately, they’ve found plenty of them.
In the United States alone, the report highlights the exotic pet trade, live animal markets, bat guano harvesting, guinea pig and ferret farming, coyote and fox urine production, roadside zoos, animal fighting, fur farming, commercial agriculture and many other potentially dangerous environments.
“This is a global problem,” said Dr. W. Ian Lipkin, a professor of epidemiology at Columbia University’s Mailman School of Public Health, who was not involved in the research.
Lipkin has long called for the closure of fresh produce markets like the one in Wuhan, China, where COVID-19 may have originated, and for stricter safety procedures at scientific research labs, like the one in Wuhan, where some believe the virus that causes COVID-19 may have started. “Finger-pointing is not productive,” he said.
So-called zoonotic diseases have always existed — smallpox, HIV/AIDS and last year’s monkeypox outbreak are other examples — but researchers believe they are becoming more common as interactions between humans and animals increase with climate change, urban expansion, global travel and other changes.
“It’s generally accepted that the more frequent these interactions are, the greater the risk of disease transmission,” said Suresh Kuchipudi, chair of the department of infectious diseases and microbiology at the University of Pittsburgh School of Public Health.
The report underscores that these problems aren’t just happening in faraway countries, said Kuchipudi, who wasn’t involved in the study but reviewed it as an independent researcher. “We always think it must be happening in some other part of the world,” he said. “We have the same kind of activities right next door. The risk exists regardless of geography and cultural practices.”
Industry resistance
Linder said his biggest concerns are industries that are “poorly regulated or not regulated at all.”
The report stresses that the U.S. mink industry should be better regulated or even eliminated because it poses a risk to human health and its products are unnecessary luxuries.
Unsurprisingly, the mink industry disagrees with the conclusion that its sector is unsafe.
Mink farmers are careful stewards of public and animal health, said Challis Hobbs, executive director of Fur Commission USA, the organization that represents U.S. mink farmers. Mink are sold through auction houses and must be certified and meet biosecurity standards to be marketed, he said by email.
At the start of the COVID-19 pandemic, U.S. mink farmers, at their own expense, helped develop and distribute a vaccine to protect mink against the SARS-CoV-2 virus, Hobbs noted.
In the United States, mink farms have long participated in weekly testing for the SARS-CoV-2 virus and are now testing sporadically, Hobbs said.
“We continue to work closely with federal, state and local agencies to take all necessary precautions to protect humans and wildlife and prevent the spread of disease,” he said. “We adhere to rigorous animal welfare and biosecurity standards, as do other livestock industries.”
Simple changes can make a big difference
Lipkin described a research trip to Saudi Arabia to study the transmission of Middle East respiratory syndrome, known as MERS, a SARS-like virus first identified in 2012.
MERS was thought to be transmitted by camels, but no one understood how people in big cities like Riyadh could catch the disease when there were no camels in the area.
Lipkin visited two slaughterhouses. As is the tradition, at sundown, each slaughters camels first, then cows, then sheep. At one slaughterhouse, butchers use high-pressure hoses to clean the animal meat before shrink-wrapping it for sale; at the other, they skip that step.
Lipkin found extremely high levels of viral material in beef and mutton in places where the pipes were not in use and no viral material where they were.
Lipkin said he remains concerned about the overuse of antibiotics in animal agriculture, which increases the risk that these essential medicines will not work when people need them.
Inexpensive genetic testing can now be used to rapidly test wild or farmed animals to determine which pathogens they are carrying that could pose a risk to humans, he said. People who work closely with the animals can also have their blood tested to see if they carry antibodies that indicate they have previously been infected with a virus transmitted by the animals.
Policy changes to reduce risks
The report proposes a series of policy changes across the 15 countries in Africa, Asia, the Americas, Europe, the Middle East and Australia. These changes include stronger regulation and oversight of animal markets and their supply chains; better protection of public health in the livestock industry, wildlife trade and wildlife farming industries; and policies that support sustainable agricultural practices.
Kuchipudi said it was a question of balancing food security, economy and the health of animals and people.
“Can we stop all animal operations?” No, he said. “That is not a solution and it is not appropriate.”
But the risks can be reduced, especially when people are informed about them, through reports like this one, Kuchipudi said.
He also said known risks should be reduced by procedures such as pasteurizing all milk and dairy products, treating animals with care and either avoiding petting zoos or ensuring children wash their hands thoroughly after touching animals and do not kiss them.
Such precautions are also important for animals, Kuchipudi said, noting that many pets have caught COVID-19 from their human family.
“We really have to recognize that by protecting our animals, we are protecting our (own) health. And vice versa,” he said. “By protecting our environment, we are also protecting human health and animal health. They are almost inseparable.”
The Mercy for Animals group, an international non-profit animal protection organization, also supports the concept, called One Health.
Mercy for Animals has launched a campaign against the use of “slaughter pigs” – pigs too sick, weak or injured to walk on their own – in the food supply.
Allowing these sick pigs into the food chain and exposing workers to them creates an unnecessary risk to human health, said Frances Chrzan, the organization’s senior director of federal policy.
Many government officials, for example, worry that pigs could contract bird flu that is circulating in poultry and dairy farms. Pigs are known to be hotbeds for the flu, which can jump from a virus that is exclusively found in animals to one that can also infect humans, as happened in the 2009 swine flu outbreak, said Dr. Walter Sanchez-Suarez, a veterinarian and animal welfare scientist at Mercy for Animals.
“It’s a ticking time bomb knowing that this virus (bird flu) is everywhere and they’re creating the perfect conditions for this zoonotic spillover event to actually happen,” he said.
You can contact Karen Weintraub at kweintraub@usatoday.com.