On September 16th, 2019, an explosion occurred at the State Research Centre of Virology and Biotechnology building (Vector) in the city of Koltsovo, in the Novosiberisk region of Siberia, Russia. The affected building was a BSL 4 virology research centre, and one of only two known sites housing variola virus, the cause of smallpox. The facility has one of the largest collections of dangerous pathogens in the world. Whilst laboratory safety breaches are common and do not usually result in epidemics, explosions are rare. Unlike a needlestick injury or an accidental shipping of live anthrax, an explosion of this magnitude is likely to lead to a physical breach of the integrity of the laboratory, possibly affecting multiple parts of the structure and equipment within. An explosion is sudden, uncontrolled and unpredictable, and involves force which may result in pathogen release into the surrounding environment. An epidemic which arises in close proximity to the explosion could spread beyond the affected region or even globally, which makes this event a concern for global public health.
