South Korea's disease control agency has reviewed its response posture against a possible domestic spillover after a death from pneumonia of unknown cause, suspected to be pneumonic plague, was reported in Irkutsk, Russia. The agency kept the domestic risk level at "low," noting that the pathogen behind the death has yet to be identified and that there is no evidence of sustained transmission.
According to the Korea Disease Control and Prevention Agency on the 13th, a worker at an anti-plague research institute in Russia's Irkutsk region was hospitalized with pneumonia symptoms on Sept. 29, deteriorated and died on Oct. 2. A total of 197 contacts, including institute staff and medical personnel, have been identified, and 189 of them are reported to be under isolation and monitoring. Whether the deceased was infected with the plague bacterium has not been confirmed.
The World Health Organization and major overseas health authorities have also assessed the risk as broadly low based on information disclosed so far. The WHO cited the absence of evidence of sustained transmission and the lack of a confirmed diagnosis for the deceased institute worker as the main uncertainties in the case.
The agency conducted a rapid risk assessment on the 7th and rated the overall domestic risk as "low." It judged the likelihood of an outbreak in South Korea as "very low" and the impact of any outbreak as "low." At a situation review meeting on the 12th, it maintained the same assessment and reviewed its systems for quarantine, surveillance, diagnosis, epidemiological investigation and the management of patients and contacts.
Pneumonic plague occurs when the plague bacterium invades the lungs, and it is designated a Class 1 notifiable infectious disease in South Korea. It can spread between people through respiratory droplets from an infected person, with an incubation period averaging one to four days. Patients develop high fever, headache, cough, difficulty breathing and chest pain, and the illness can progress to severe pneumonia. It can be treated with appropriate antibiotics, and no plague patient or plague-infected rodent has ever been found in South Korea.
"We plan to strengthen surveillance, focusing on arrivals with a history of visiting or staying in Russia who have fever or respiratory symptoms," the agency said. "If the risk level rises going forward, we will also pursue adding Russia to the list of countries subject to enhanced quarantine screening."
