The World Health Organization (WHO) notified this Monday that the cause of the eleven cases of severe pneumonia detected in the Argentine city of San Miguel de Tucumán, which have already caused four deaths, is the legionella bacterium.
The cases were initially reported as pneumonia of unknown cause and last Friday Legionella bacteria were identified as the organism causing the disease outbreak.
All the cases presented between August 18 and 25 in a health center in the Argentine city with symptoms of pneumonia, fever, muscle and abdominal pain and breathing difficulties.
Of the eleven cases, eight are health workers from the center and three are patients from the health facility. Three of the four deceased were health personnel.
Legionellosis is a disease similar to pneumonia and its severity varies from a mild febrile state to a severe and sometimes fatal form of pneumonia. The most common way of transmission of legionellosis is the inhalation of contaminated aerosols from contaminated water sources.
Causes linked to aerosolized Legionella transmission and legionellosis outbreaks include air conditioning cooling towers or condensers associated with air conditioning and industrial refrigeration, hot and cold water systems, humidifiers and whirlpool spas
The UN agency recommends continuing laboratory controls, case identification and clinical care, contact tracing, investigation of the outbreak to identify the source(s), application of measures to prevent new infections and improving infection prevention and control measures.
The organization advises against applying any restrictions to travel or trade with Argentina based on currently available information about this event.
The Ministry of Health of Argentina notified the WHO on August 29 of a report from the Ministry of Public Health of the province of Tucumán on a group of six cases of bilateral pneumonia identified in the city of San Miguel de Tucumán, in the province of Tucumán .
The six cases were linked to a private health center in the city, with the onset of symptoms between August 18 and 22. Those affected were five health workers and a patient who was admitted to the clinic for an unrelated condition and who was later admitted to the intensive care unit after presenting with pneumonia.
On September 1, three more cases were identified – all of them health workers from the same private health center, aged between 30 and 44 years – with signs and symptoms similar to the six initial cases. The first symptoms of these cases occurred between August 20 and 25.
Between September 2 and 3, two other cases were identified, an 81-year-old man and a 64-year-old man, both with comorbidities, who were hospitalized and presented a clinical picture similar to that of the previous cases.
The average age of the cases is 45 years; seven are men. Ten cases had underlying conditions and/or risk factors for severe disease, including the four reported deaths. Four cases remain hospitalized as of September 3. Contacts of the cases are receiving care and, to date, none have developed symptoms.