Pneumonic plague concern: Here’s what we know, and don’t know, about a suspicious death and Russian secrecy

By Sian Wilkerson

The recent death of a pathogen researcher working in Siberia has raised concerns worldwide about suspected pneumonic plague.

Darya Shipilova, a 28-year-old laboratory scientist who worked at Russia's Irkutsk Anti-Plague Research Institute, died Oct. 2 after being hospitalized four days earlier. Those basic facts aren't in dispute - but just about everything else is, Virginia Commonwealth University's Judyth Twigg said.

Twigg, Ph.D., is a professor in the Department of Political Science in the College of Humanities and Sciences, and her research focuses on health, demography and health systems reform in Eurasia. She spoke to the Associated Press this week about the circumstances surrounding Shipilova's death and its aftermath.

VCU News caught up with Twigg for the latest on the case - and how it continues a decadeslong pattern of mystery from Russia on the world stage.

What has Russia actually said and done about Shipilova's death so far?

Russia's federal public health agency says Shipilova had "pneumonia of unknown etiology," that testing found no microorganisms linked to her work and that no accident occurred at the institute. Unconfirmed Russian media accounts have her either breaking a test tube of plague bacteria at her lab a week earlier or bringing the disease home from Thailand.

Russia's on-the-ground response has been comprehensive and fast. Roughly 200 contacts went under medical observation, several Irkutsk hospitals were quarantined, and Anna Popova, Russia's chief sanitary doctor, flew five time zones from Moscow to supervise in person.

By Oct. 7, the agency said its work was done: 5,000 tests among contacts had found no dangerous pathogens - just two cases of COVID-19 and two of rhinovirus. But the World Health Organization still says it doesn't know what killed Shipilova.

Why is getting confirmation of Shipilova's cause of death so difficult at the moment?

Partly because confirmation may genuinely not exist yet.

An Irkutsk clinician told the Russian local media outlet People of Baikal -which is blocked inside Russia and was branded a "foreign agent" in January - that a definitive laboratory result for plague can take up to 10 days, and that no cause of death could have been established the day after an autopsy. Russian authorities told WHO the illness first looked like an ordinary respiratory infection.

Russian laboratories may simply be holding inconclusive results rather than hiding damaging ones.

But Russia's reaction to Shipilova's death is instructive, isn't it?

The way Russian authorities have behaved tells us more about their system than about the actual incident.

In Russia, the authority to describe an emergency belongs to Moscow, and officials below run a real risk getting out ahead of it. The governor of neighboring Buryatia posted that a woman had "died of plague" in Irkutsk, then two hours later edited in the word "possibly." A town administration near Irkutsk urged residents to stay away, then deleted the warning.

Every correction came within hours, clearly mandated from higher up. The Kremlin's spokesman, Dmitry Peskov, has dismissed most media reporting as "false information" - which, under 2020 statutes, can carry criminal penalties.

The effect on the ground is a strange kind of blankness. In Shelekhov, the satellite town outside Irkutsk, a reporter this week found the parks and cafes busy and almost nobody masked. Outside the closed hospital where Shipilova died, a guard said: "We only read about it all online."

Has anything like this - a mysterious outbreak - happened in Russia before?

Yes, several times, following a pattern that goes back decades.

When a Soviet artist came home from India with smallpox in 1959, Moscow isolated thousands, suspended travel, vaccinated millions - and said nothing publicly. Twenty years later came Sverdlovsk, where a filter failure at a secret bioweapons facility released anthrax that killed at least 64 people. The government blamed contaminated meat and held that line for 13 years, until Boris Yeltsin, the regional party boss at the time, admitted where it came from.

The work these institutes do is real science, necessary and unglamorous: tracking plague in wild rodents across Siberia, testing whether antibiotics still kill the local strains (which is what Shipilova worked on), developing vaccines. But the institutes were never purely civilian. The Soviet weapons program drew virulent strains from their collections and ran classified research through them.

That history is why there's been so much speculation this week that something engineered escaped, but there is zero public evidence for that (so far). Plague specialists say the institute's published work looks ordinary, and roughly 200 monitored contacts have produced no secondary cases.

Should the American public be concerned?

Not about the disease itself. The CDC puts the risk to the United States at "extremely low." Pneumonic plague doesn't spread easily. Transmission requires prolonged close contact with someone who is coughing, nothing like measles or COVID-19.

Plague is endemic to the United States, too. A handful of Americans contract it every year, almost all in the rural West. In July 2025, a man in northern Arizona died of pneumonic plague within hours of reaching the hospital. Forty-six people near him - family, coworkers, hospital staff - were given a week of antibiotics, and not one fell ill.

Based on the evidence currently available, the real story here isn't plague, engineered or otherwise. Instead, it's a Russian government that won't say plainly what killed one of its own scientists, or even that it doesn't yet know.

That's not new. The Russian government's first instinct with bad news has always been silence and cover-up, and that reliably produces the very thing it's meant to prevent: rumor, speculation - and a world assuming the worst.