U.S. and global health officials are calling on Russia to share more information after Russian media reports said a scientist at an infectious disease research center in Siberia died after possibly contracting plague during a laboratory accident. The reports have caused concern, even as the World Health Organization says “the public health risk to the general population appears to be low,” based on current information. Céline Gounder, a CBS News medical contributor and public health editor at large for KFF Health News, echoed that belief on “CBS Mornings” Tuesday. “The American public has nothing to worry about,” he said. Still, the official cause of death has not been made public, and a lack of transparency on Russia’s part has led some experts to question whether the lab worker had the plague. “The response doesn’t fit the plague. It’s not consistent with the plague,” Dr. Amesh Adalja, a senior researcher at the Johns Hopkins Center for Health Security, told CBS News. “Plague is something that, in the 21st century, can be treated with antibiotics.” This is what you should know. Concern about the situation in Russia Russian media reported that a researcher, identified as Darya Shipilova, 28, died after being exposed to plague in a laboratory accident at the Irkutsk Anti-Plague Institute. Initial reports said Shipilova broke a test tube containing the plague bacteria Yersinia pestis in late September, fell ill with severe pneumonia, and died from her illness. The World Health Organization said Shipilova died of severe pneumonia during the night of October 2. Russian officials have since cast doubt on those reports. Russia’s health watchdog, Rospotrebnadzor, said there was no accident and that Shipilova had died of “pneumonia of unknown origin.” A maintenance worker leaves the headquarters of Russia’s health and consumer watchdog, Rospotrebnadzor, in Moscow on October 5, 2026. Igor Ivanko/AFP via Getty Images The WHO said Russia informed it on October 6 that no pests were detected. The global health agency said it asked Russian authorities to provide information on which pathogen caused Shipilova’s illness. Secretary of State Marco Rubio on Tuesday called on Russia to be more transparent and said the nation should “share more information with the world.” A State Department spokesperson later told CBS News that the U.S. Embassy in Moscow had “communicated Russian authorities about the reported death” and “requested additional information,” which it encouraged Russia to share “promptly and transparently.” The WHO said it is closely monitoring the situation and requesting more information from Russian authorities. What is the plague? Plague is caused by the bacteria Yersinia pestis. There are three main types of plague: bubonic, septicemic and pneumonic. Bubonic plague is the most common form of plague. Infected people may have painfully swollen lymph nodes known as buboes, along with fever and chills, severe headache, body aches, and exhaustion. Septicemic plague occurs when the bacteria Yersinia pestis enters the bloodstream. Patients may develop fever, chills, extreme weakness, abdominal pain, shock, and possible internal bleeding. Some of the skin may turn black and die. A microscopic image shows the bacteria Yersinia pestis, which causes plague infections in humans. Ruslanas Baranuskas/Science Pho/Getty Images Pneumonic plague usually occurs when other forms of plague are left untreated and the bacteria Yersinia pestis infects the lungs. Patients develop pneumonia and may have fever, headache, weakness, difficulty breathing, chest pain, cough, and bloody or watery mucus. Pneumonia could cause respiratory failure. This is considered the most serious version of the plague and is always fatal if untreated. Russian media reports indicated that Shipilova may have died of pneumonic plague. How does the plague spread? Plague is most commonly transmitted through the bite of fleas carried by infected rodents. Animals, including dogs and cats, can also become infected by eating smaller animals that carry these fleas. Pneumonic plague can be transmitted between people. In cases of pneumonic plague, droplets emitted when a sick person coughs can infect other people. Russia’s health watchdog said nearly 200 people who had been in contact with Shipilova before her death were tested and none had plague. This undated photograph released in 2019 by the Siberian and Far Eastern Plague Research Institute in Irkutsk shows workers at the institute in a laboratory. Irkutsk Siberian and Far Eastern Plague Research Institute via AP How is the plague treated? Plague can be successfully treated with antibiotics, health organizations and doctors say. Patients should receive treatment as soon as possible. Researchers who regularly work with plague can also get vaccinated against it, Gounder noted. Plague outbreaks in the Middle Ages killed millions of people, due to common and widespread flea and rat infestations and a diminished understanding of how to prevent the spread of disease. About seven cases of plague are reported in the United States each year, according to the Centers for Disease Control and Prevention. More than 80% of cases in the United States are bubonic plague, the agency said. Most cases in the United States occur in the West and Southwest. Cases are often treated successfully, according to CDC data. The last fatal case of plague in the US was recorded in 2021. Edited by Nicole Brown Chau More from CBS News Go deeper with The Free Press In:
