A 28-year-old woman died in Russia last week and, since then, speculations about the case have ricocheted around the globe.
The woman was a lab technician at a Russian research institute that studies the plague. As unverified rumors have circulated that she may have contracted the disease from a lab leak, President Trump, the World Health Organization and other leaders are asking for more information.
Russia has insisted this is not a health emergency and stated that its health authorities have not found dangerous pathogens in any of the deceased woman's contacts.
But there are still far more questions than answers.
That uncertainty has global leaders and health experts turning to a law that obligates countries, including Russia, to share exactly this type of information. It's called the International Health Regulations or IHR.
On Wednesday, at a WHO press conference, Director General Tedros Adhanom Ghebreyesus invoked IHR as the best way to determine current situation in Russia and determine the appropriate response.
"We don't yet have the full picture of this event," he said. "Timely, complete and transparent information sharing under the international regulations is essential to clarify conflicting reports and enable an accurate assessment of potential public health risks."
Here are the key things to know about the IHR and how it applies in today's world.
Rooted in the 19th century
This law requires countries to share health information that could have international implications. It goes way back to the 1850s with cholera outbreaks in Europe, which led to the creation of guidelines for sharing disease information.
"That's very, very long for international law," says Alexandra Phelan, an associate professor at the Johns Hopkins Bloomberg School of Public Health and senior scholar at the Johns Hopkins Center for Health Security. "Look at the negotiation documents and they're debating: Is cholera caused by a bacteria or miasma [a bad smell]? Like we're really right in the middle of germ theory."
Then, when WHO was founded in 1948, these regulations — then called the International Sanitary Regulations — were adopted. That was one of the organization's first moves. The law has since been amended and updated, most notably after the SARS or Severe Acute Respiratory Syndrome outbreak in 2003 and most recently due to COVID-19 pandemic.
A country is supposed to notify WHO if the health event has the potential to cause an international health emergency.
Today, IHR is among the most widely ratified international treaties, with 197 signatories including the U.S. and Russia. (Even though the Trump administration says it has withdrawn from WHO, the U.S. is still bound by the IHR with the exception of some recent amendments.)
One of the core obligations in the law "is that parties or states must notify WHO within 24 hours of detecting a [serious health] event," explains Phelan.
Some events – like a case of smallpox or a new type of influenza — should immediately trigger a notification. For other situations, a checklist helps a country assess whether notification is needed.
Each year, she says, WHO receives thousands of notifications from all over the world and most turn out to be nothing.
The situation in Russia
Some people fear the Russian woman — who died Oct. 2 — had pneumonic plague. That's one of the diseases "explicitly listed" under IHR, says Phelan, as something to assess and notify the WHO.
However, Russia did not notify WHO about this woman's death. Instead, WHO learned about it through media reports and then, on Oct. 3, went to Russia seeking verification and additional information.
"Russia's response, firstly, was delayed," says Phelan. "But also it wasn't comprehensive."
It took Russia several days to respond. On Oct. 6, health officials told WHO there were no cases of plague in the region and that the woman was hospitalized with severe pneumonia of unknown origin before she died. They also explained that health authorities had placed about 200 contacts in quarantine.
WHO asked Russia for more information, including about lab tests conducted, public health measures and the health status of the woman's contacts. However, as with many international laws, there's no mechanism to make countries comply with the law and share information.
Phelan says the next few days and weeks will be key in understanding how much information Russia is going to share. If they aren't fully transparent, she hopes pressure from other countries either convinces Russia to comply with IHR or, at least, helps keep up the norm of other countries respecting IHR and notifying WHO about future health events.
That kind of notification is critical if the world is to be ready to respond and contain future outbreaks, says Lawrence Gostin, who directs the WHO Center on Global Health Law and is a professor at Georgetown University.
"This case shows the good, the bad and the ugly of the IHR," he says.
"Legally, this is the only thing that's holding Russia to account," Gostin explains. And yet, "you have countries that are hiding the ball."
He believes that the risk to the general population from the current situation in Russia is likely very low. But, for him, the fact that countries can disregard the IHR notification requirements is a "blaring siren about how unprepared we are" to quickly control health threats.
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