Russia has denied reports of a second suspected infectious disease case following the death of a 28-year-old researcher at a Siberian anti-plague laboratory. The World Health Organization says it has asked Moscow to verify reports that another employee developed pneumonia of unknown cause after the first worker fell ill. Russian authorities have dismissed the reports as false, saying checks on contacts and nearly 5,000 laboratory tests found no evidence of dangerous pathogens. The case has drawn international scrutiny, with questions still being raised about the circumstances surrounding the researcher's death. #russia #plague #health #news #Science