Russia denies plague as WHO seeks answers over Siberian lab worker death

A researcher at one of Russia's specialist plague institutes in Siberia has died, and Moscow says the cause was pneumonia of unknown origin rather than plague. The World Health Organization has asked Russia for more information, around 200 contacts have been quarantined, and four Central Asian countries have stepped up border health checks.

Daria Shipilova, 28, worked at the Irkutsk Anti-Plague Research Institute in southeastern Russia, near the Mongolian border. She fell ill and died last Friday. Unconfirmed reports said she had broken a test tube containing live pneumonic plague bacteria while collecting samples, then went to hospital with symptoms of severe pneumonia and died two days later.

Russia's public health watchdog has rejected that account. It said it found no evidence of an accident at the research centre, named the official cause of death as pneumonia of unknown origin, and said no further infections of a similar kind had been detected among institute staff in the past 10 days. Kremlin spokesman Dmitry Peskov told journalists that Russia was providing comprehensive information through the watchdog. He said it was good when countries offered each other assistance, without saying whether Russia would accept an American offer of help. Moscow also made a counter offer to help the United States with its measles outbreak.

The institute itself has been locked down, with reports that around 60 staff were still inside. Several hospitals in the Irkutsk region were placed under a three-week quarantine, and about 189 close contacts of the dead woman were traced. Russian authorities said none had shown signs of being unwell. The Russian state news agency TASS said reports of a second case of pneumonic plague were false, describing them as fake social media information.

The World Health Organization has been in contact with Russian officials. It assessed the risk as very low for the European region, low for the Russian Federation and medium to low for the Irkutsk region. The UK Health Security Agency said it was seeking further information and that the risk to the UK population remained very low.

Neighbouring countries have not waited. Kazakhstan tightened health controls at border checkpoints, Tajikistan and Kyrgyzstan followed, and Uzbekistan began setting up quarantine centres. China was reported to have restricted access from Russia and introduced temperature checks on Russian flights. The United States said it was monitoring the situation closely. Secretary of State Marco Rubio said it was incumbent on Russia to share more information, adding that it would be reckless to speculate given how little is known. President Donald Trump offered US help and said he planned to speak to Vladimir Putin about the case.

Pneumonic plague is caused by the same bacterium as bubonic plague, Yersinia pestis. It affects the lungs, can spread from person to person through respiratory droplets and, untreated, kills more than half of those infected, sometimes within 24 hours. It is less transmissible than COVID-19. Early treatment with antibiotics is effective, and a vaccine exists. There is no widely available vaccine, according to Professor Sir Andrew Pollard of Oxford, who is working on one.

Plague is not extinct. Between 1,000 and 3,000 cases are recorded worldwide each year, and six countries have had confirmed cases in the past six years, with 423 deaths, mostly in the Democratic Republic of Congo and Madagascar. It remains endemic in parts of Russia, China, the United States and Africa.

The official Russian account has not stopped speculation about the laboratory itself. The Irkutsk institute was part of the Soviet Biopreparat biological weapons programme during the Cold War, and some experts say it has continued dual-use work. Russia denies modifying diseases to create treatment-resistant bioweapons. Andy Weber, a former US assistant secretary for chemical, nuclear and biological defence programmes, said the worker had been researching antibiotic-resistant strains of plague and had published papers on it. Investigative journalist Annie Jacobsen said the possibility that the case was primary pneumonic plague, rather than a secondary infection following bubonic plague, raised questions about whether the pathogen had been engineered. Both said the risk of wider spread was limited.

Colonel Hamish de Bretton-Gordon, a former British Army officer, said there was no need to panic but reason to be concerned, because the death could be either an innocent laboratory accident or something more sinister. He noted that Siberia's isolation and Russia's reduced travel links after the war in Ukraine made a COVID-style global spread unlikely.