What happens when biology crosses the boundaries of international law — one virus, translated again and again into a different legal object.
Imagine that an unfamiliar virus is discovered in animals on a farm. At first, nobody knows whether it can infect people: veterinary authorities investigate, samples are collected, laboratories begin sequencing, and animal movements may be restricted while investigators try to establish how widely it has spread. Several days later, a farm worker becomes ill; the virus is detected in the patient’s sample, and genomic analysis shows it is closely related to the virus identified in the animals. Another case appears, and then another country identifies a traveller carrying the same virus.
The genome is uploaded to an international database. Laboratories around the world download it, diagnostic developers begin designing tests, researchers request physical samples, and vaccine manufacturers begin examining whether existing platforms could be adapted. Governments consider restrictions on animals and animal products from the affected country. Within a matter of days, one biological event has moved through animals, people, laboratories, digital infrastructure and international trade.
The virus has not changed legal identity deliberately. International law has changed around it. The animal infection engages one system; human transmission engages another; sharing the pathogen and its genetic information raises another set of rules; and restricting trade introduces yet another — with national sovereignty beneath all of them. This is one of the fundamental difficulties of global One Health governance: biology moves continuously through systems that law governs separately. It is the companion journey to our map of who actually governs a global outbreak.
Stage one: an animal disease
Our hypothetical virus begins in livestock, and at this point the principal international architecture is animal health. The World Organisation for Animal Health (WOAH) provides international standards and maintains the World Animal Health Information System (WAHIS), through which countries report important animal-disease information, while the WOAH Terrestrial Animal Health Code sets standards intended to support early detection, reporting, prevention and control of animal diseases and zoonoses while facilitating safe international trade. National veterinary authorities sit beneath that architecture: farmers and veterinary surgeons may provide the first observations, diagnostic laboratories identify the organism, epidemiologists investigate movements and contacts, and governments decide what domestic control measures are appropriate. For this first stage, the arrangement appears logical — it is an animal-health problem being handled by animal-health institutions. Then a human becomes infected.
Stage two: the same virus becomes a public-health event
Biologically, remarkably little may have happened — a virus circulating in animals has crossed into a person — but institutionally, everything changes. Human-health surveillance becomes relevant, clinical laboratories become involved, and public-health authorities begin investigating exposures and contacts. If the event may have international implications, the International Health Regulations (2005) enter the picture, providing the principal international framework for detecting, assessing, notifying and responding to public-health events capable of spreading internationally. The virus is therefore now visible through at least two international systems: WOAH may be receiving information about disease in animals, and WHO may be receiving information about infections in humans. One pathogen has already become two governance problems — the mechanics of which our explainer on the International Health Regulations sets out in full.
The handover that should not be a handover
This is where conventional institutional thinking can become misleading, because the appearance of human cases should not mean that an event is handed from veterinary authorities to public-health authorities. The animal epidemic has not disappeared, and understanding infection in animals may be essential to understanding the human risk: which species are susceptible, how prevalent infection is, whether infected animals are symptomatic, whether they can transmit before showing signs, whether wildlife maintains the pathogen, which occupational groups are exposed, and whether animal movements are spreading it geographically. Those questions remain relevant to the human outbreak. The appropriate model is therefore not animal health → human health, but animal health ↔ human health, with information moving in both directions. That is easy to draw on a One Health diagram; making it happen across separate ministries, laboratories, international organisations and legal systems is considerably harder.
Stage three: the pathogen becomes data
Our hypothetical virus is sequenced, and within hours its genome can be available to researchers around the world — one of the extraordinary achievements of modern infectious-disease science. Scientists in countries with no cases can begin examining the pathogen immediately, diagnostic assays can be designed, mutations can be monitored, and relationships between isolates can be reconstructed. The physical pathogen remains in a laboratory, but its informational representation has become global, and that creates a completely different governance problem. A tube containing virus and a digital genome sequence do not move through the world in the same way: physical material can be stored, packaged, transported and transferred under agreements, whereas digital sequence information can be copied almost perfectly and distributed globally within seconds. Once downloaded, it can be analysed, combined with other information and used in research and product development far from where the pathogen was identified. The speed of science therefore begins to collide with legal frameworks built around physical biological resources.
Stage four: biodiversity law enters the outbreak
Why should biodiversity law have anything to do with an emerging virus? Because pathogens are biological resources. The Convention on Biological Diversity established principles concerning national sovereignty over genetic resources and the fair and equitable sharing of benefits arising from their utilisation, and the Nagoya Protocol, which entered into force in 2014, developed a more detailed access-and-benefit-sharing framework. The underlying principle responds to a legitimate historical problem: biological resources collected in one country should not simply be removed, commercially exploited elsewhere and generate benefits from which the provider receives little or nothing.
Then apply that principle to an outbreak. The world needs rapid access to the pathogen, but the country that identified it may reasonably ask what happens if researchers and companies use that material to develop valuable diagnostics, therapeutics or vaccines — what benefits return, what happens if the products are priced beyond its reach, and what happens if manufacturing capacity is concentrated elsewhere. Suddenly, rapid pathogen sharing and equitable benefit sharing become parts of the same governance problem.
PABS attempts to build the bridge
This is why the proposed Pathogen Access and Benefit-Sharing system, or PABS, matters so much. The WHO Pandemic Agreement, adopted by the World Health Assembly in May 2025, envisages a multilateral system through which pathogen materials and genetic sequence information concerning pathogens with pandemic potential can be shared rapidly while benefits arising from their use are shared more equitably. The principle is deliberately reciprocal: the world needs pathogens, and countries need confidence that sharing them contributes to access to the products subsequently developed. The adopted Agreement envisages participating manufacturers providing WHO with rapid access to a proportion of real-time production of relevant vaccines, therapeutics and diagnostics during a pandemic emergency — a target corresponding to 20 per cent of production, through donations and affordable access.
The details of the PABS system remained under negotiation through 2026, and that unfinished negotiation is important because it sits precisely at the interface between two legitimate objectives: speed and equity. A pathogen-sharing system that is equitable but too slow to support outbreak science is inadequate; a system that moves pathogen information instantly while repeatedly leaving provider countries unable to obtain resulting products will eventually undermine trust. The governance challenge is achieving both — the same tension our analysis of who owns the warning examines directly.
But what exactly is being shared?
The digital age makes this more difficult. A physical virus sample is clearly biological material — but what about its genome? The international debate surrounding digital sequence information, often abbreviated DSI, reflects a broader problem extending well beyond pandemic preparedness, because genetic sequence data can contain much of the information researchers require to study a biological resource without their obtaining the physical material itself. The Convention on Biological Diversity has consequently spent years addressing how benefits arising from uses of DSI should be shared, and at COP16 in 2024 parties agreed a multilateral mechanism and established the Cali Fund, associated with benefit sharing from uses of digital sequence information on genetic resources. PABS is being negotiated within this changing landscape, so the same pathogen sequence may sit at the intersection of pandemic preparedness, scientific openness and evolving biodiversity benefit-sharing arrangements. The technology can copy the genome instantly; international governance has to decide what obligations should follow the copy.
Stage five: somebody develops a vaccine
Suppose our hypothetical virus continues spreading. Research groups develop diagnostic assays, a biotechnology company develops a promising vaccine, and another company identifies an antiviral candidate. Now the pathogen has become part of an innovation system, and questions of manufacturing capacity, regulatory approval, intellectual property, technology transfer, procurement and distribution appear. This is where the experience of COVID shaped the Pandemic Agreement particularly strongly, because scientific success does not guarantee equitable access: a vaccine can exist while countries remain unable to obtain it, a diagnostic can be technically available while laboratory systems lack access, manufacturing can be concentrated in a few regions, and supply contracts can allocate early production long before global need is understood. The Pandemic Agreement therefore addresses not only surveillance and pathogen sharing but also production capacity, supply chains, research and development, regulatory strengthening and access to pandemic-related health products. Detecting a threat is only the beginning; preparedness also means being able to manufacture and distribute the tools required to respond.
Stage six: governments close borders to products
Now imagine that the virus is also causing serious disease in livestock. Other countries become concerned about importing infected animals or contaminated animal products, and trade restrictions begin — the event has entered another legal regime. The World Trade Organization’s Agreement on the Application of Sanitary and Phytosanitary Measures (the SPS Agreement) recognises governments’ right to take measures necessary to protect human, animal and plant life or health, while imposing disciplines on those measures so that health protection does not simply become a convenient justification for arbitrary discrimination or disguised protectionism; measures should be based on scientific principles and risk assessment. International standards play an important role here — WOAH standards for animal health and zoonoses, Codex Alimentarius for food safety, and the International Plant Protection Convention for plant health. Our virus has therefore moved again: it began as an animal-health event, became a human-health event, its genome became an access-and-benefit-sharing issue, products developed from it created equity and manufacturing questions, and now control measures have made it an international trade issue — the same terrain our analysis of the post-Brexit UK border explores. The virus remains the same virus.
Four legal systems, or considerably more?
The title of this article deliberately simplifies the problem, because there are more than four legal systems potentially involved: public-health law, animal-health standards, biodiversity law, trade law, data protection, intellectual property, national emergency legislation, product regulation, environmental law and occupational-health law — and, depending on the pathogen, food law too. The important point is not the precise number; it is that the biological event is continuously being translated into different legal objects. A veterinary authority sees an animal disease; a public-health authority sees human infection; a biodiversity regime sees genetic resources and sequence information; a trade ministry sees an SPS measure; a pharmaceutical regulator sees a medicinal product; and a government sees an emergency requiring sovereign decisions. Each perspective is legitimate. None sees the whole system automatically.
Then national sovereignty sits underneath it all
There is no international organisation waiting to take control when a pathogen becomes sufficiently serious. WHO does not become a global government when a PHEIC is declared; the World Health Assembly’s adoption of the Pandemic Agreement did not transfer national health powers to Geneva; and the International Health Regulations do not allow WHO to order national lockdowns or vaccination mandates. States retain sovereign authority over domestic health policy, and international agreements work because countries accept obligations to cooperate, notify, prepare, share information or behave according to agreed rules. This creates a distributed governance system whose effectiveness depends on countries performing their parts while maintaining sufficient interoperability for the international system to function. That can work remarkably well — and it can also create delay.
Nobody owns the biological event
This brings us to the central One Health problem. Who owns our hypothetical outbreak — the agriculture ministry, the health ministry, WHO, WOAH, the laboratory, the country where the virus emerged, or the countries where human cases appeared? Nobody does, and perhaps nobody should, because a single institution attempting to govern every biological, commercial, environmental and public-health dimension of an emerging pathogen would itself create enormous problems. The weakness is not necessarily distributed responsibility. The weakness is poorly connected responsibility. One Health governance should therefore not be understood simply as a demand to merge institutions; it should be understood as the design of the interfaces between them.
The interface is where time disappears
Imagine that veterinary surveillance identifies an unusual virus on Monday, but human-health authorities receive the information on Thursday; a related human infection was actually detected on Tuesday, yet nobody connects the two datasets until Friday; genomic sequencing confirms the relationship over the weekend; international notification occurs on Monday; researchers request samples immediately, but access arrangements take another week; and meanwhile countries begin restricting imports. None of these delays necessarily reflects negligence — each institution may have followed its own procedures — yet the biological system has gained time because the governance system is fragmented. This is governance latency at international scale, and the important metric is not simply how quickly each institution performs its individual task; it is how quickly the system converts distributed observations into shared understanding.
One Health needs legal interoperability
The solution is unlikely to be one enormous global One Health treaty replacing everything that already exists. The IHR solve problems the WTO was never designed to solve; trade rules address issues WHO should not determine; biodiversity law protects interests that cannot simply disappear whenever health authorities want access to biological resources; and WOAH provides animal-health expertise that should not be absorbed into a human-health organisation. Specialisation has value. What is missing is stronger legal and operational interoperability: when an event crosses from animal health into human health, information should move with it; when pathogen sharing intersects with biodiversity obligations, researchers should know which rules apply without losing crucial outbreak time; when trade measures are introduced, epidemiological information should be capable of supporting rapid, proportionate risk assessment; and when genomic information reveals that apparently separate events are connected, institutional boundaries should not prevent the corresponding investigations from connecting. The objective is not one legal system. It is systems that can talk to one another.
What could improve?
International exercises should begin outside human health. Pandemic exercises too often begin with human cases already recognised; a genuine One Health exercise should begin with an ambiguous animal, food or environmental signal and test how long it takes to reach public-health surveillance.
Governance latency should be measured. After significant outbreaks, investigators should reconstruct not only the epidemiology but the movement of information — when evidence existed, who held it, when it crossed institutional boundaries and when its significance became clear.
PABS should prioritise predictability as well as equity. Laboratories and provider countries need to understand in advance how materials and sequence information can be shared and what benefit-sharing obligations follow; negotiating basic rules after an emergency begins is itself a preparedness failure.
Animal and environmental surveillance should be connected to international pandemic intelligence earlier. A zoonotic pathogen should not need to demonstrate sustained human transmission before information held by other sectors receives serious pandemic attention — a point our analysis of wastewater surveillance makes at national scale.
Trade and health authorities should exercise together. Decisions about sanitary restrictions can have enormous epidemiological and economic consequences, yet the institutions making them may operate through different professional cultures.
Above all, One Health should be treated as an interface requirement — telling us not merely which sectors ought to cooperate, but where their laws, data and decision processes need to connect before an emergency occurs.
Follow the pathogen
There is a simple test for whether an international governance system is genuinely One Health: follow the pathogen. Start with the animal in which it was detected; follow the sample into the laboratory; follow the infection into a human; follow the genome into a database; follow the physical isolate into another laboratory; follow the sequence into a diagnostic or vaccine-development programme; follow the resulting product into global procurement; and follow the disease-control measure into international trade. At every transition, ask one question: did the information move with the biology? If the answer is no, we have found a governance gap.
International law does not need to become biologically seamless, but the interfaces between its different regimes need to become fast enough that institutional boundaries do not give biological threats an unnecessary advantage. One pathogen can pass through four legal systems before breakfast. The challenge is making sure those systems realise they are all looking at the same thing.
Related One Health Security analysis
This piece is part of our Rules of Outbreaks series on global health law. It is the journey companion to Who Governs a Global Outbreak? (the architecture), and connects to The International Health Regulations (the backbone) and Who Owns the Warning? (pathogen sharing and PABS).
Correct at the time of writing (August 2026): the 2024 IHR amendments are in force, but the WHO Pandemic Agreement and its Pathogen Access and Benefit-Sharing (PABS) annex remained under negotiation.
Questions & Answers
When a virus jumps from animals to a person, does the animal outbreak stop mattering?
No. The article is explicit that this should not be treated as a handover from veterinary to public-health authorities. The animal epidemic has not disappeared, and understanding infection in animals — which species are susceptible, whether animals are symptomatic, whether wildlife maintains the pathogen — remains essential to understanding the human risk. The model is animal health ↔ human health, not animal health → human health.
What is PABS?
PABS, the Pathogen Access and Benefit-Sharing system, is envisaged by the WHO Pandemic Agreement, adopted by the World Health Assembly in May 2025. It aims to let pathogen materials and genetic sequence information be shared rapidly while benefits from their use are shared more equitably — including a target corresponding to 20 per cent of participating manufacturers’ real-time production of relevant vaccines, therapeutics and diagnostics during a pandemic emergency.
What do the Nagoya Protocol and the Cali Fund have to do with an outbreak?
The Nagoya Protocol, in force since 2014, developed the Convention on Biological Diversity’s access-and-benefit-sharing principles for genetic resources. Because a pathogen is biological material, sharing it can raise the same questions the Protocol was built to answer. The Cali Fund, agreed at CBD COP16 in 2024/2025, extends benefit sharing to digital sequence information — relevant because a pathogen’s genome can be copied and shared globally within seconds.
Does declaring a global health emergency give WHO control over affected countries?
No. The article notes that WHO does not become a global government when a PHEIC is declared, and that the World Health Assembly’s adoption of the Pandemic Agreement did not transfer national health powers to Geneva. National sovereignty sits underneath the whole system.
What is the “follow the pathogen” test?
It is a simple check the article proposes for whether an international governance system is genuinely One Health: trace the pathogen from the animal in which it was detected through to the laboratory, the human case, the genomic database, and eventually the product or trade measure, and at every transition ask whether the information moved with the biology. If the answer is no, that is a governance gap.
References and further reading
- World Health Organization. International Health Regulations (2005), as amended.
- World Health Organization (2025). Amended International Health Regulations enter into force. 19 September 2025.
- World Health Organization (2025). WHO Pandemic Agreement. Adopted 20 May 2025.
- World Health Organization (2026). Member States continue negotiations on the PABS annex. 20 July 2026.
- Convention on Biological Diversity. Convention on Biological Diversity: text and annexes; and the Nagoya Protocol.
- Convention on Biological Diversity (2024/2025). The Cali Fund — benefit-sharing from the use of digital sequence information on genetic resources.
- World Organisation for Animal Health. World Animal Health Information System (WAHIS) and the Terrestrial Animal Health Code.
- World Trade Organization. Agreement on the Application of Sanitary and Phytosanitary Measures; with Codex Alimentarius and the International Plant Protection Convention.
Key Takeaways
- One biological event moves continuously through animals, people, laboratories, digital databases and international trade — but international law is organised by sector, so the same virus is repeatedly translated into a different legal object as it travels.
- A human case does not "hand over" an outbreak from veterinary to public-health authorities: the animal epidemic still matters, so the model is animal health ↔ human health, with information moving both ways.
- A genome can be copied and shared globally in seconds, which collides with biodiversity law (the CBD, the Nagoya Protocol and the new Cali Fund for digital sequence information) and with the still-unfinished PABS system — the pathogen becomes digital faster than the law can decide what that means.
- Nobody owns the biological event, and perhaps nobody should; the weakness is not distributed responsibility but poorly connected responsibility, so the fix is faster interfaces between regimes — tested by a simple rule: follow the pathogen, and ask at every transition whether the information moved with it.