Legionella: cause of pneumonia cluster identified in Argentina


A group of pneumonia cases in Tucumán, Argentina, have been caused by legionella, the bacterium that causes Legionnaires’ disease, the Pan American Health Organization said.

As of Saturday, a total of 11 cases of pneumonia have been identified as part of the outbreak associated with a health clinic in the city of San Miguel de Tucumán, including four deaths in patients with underlying health conditions, the organization said. .

All cases experienced symptoms of bilateral pneumonia, fever, body aches, abdominal pain and shortness of breath between August 18 and 25 and are epidemiologically linked to the health facility, according to a World Health Organization statement released on Monday. Of the 11 cases, eight are health workers from the facility; three are patients from the health facility. Three of the four deaths were among health care workers. Four cases were still hospitalized as of Saturday.

Blood, respiratory tract and tissue samples were obtained from the 11 cases, and preliminary tests conducted at the local public health laboratory were negative for respiratory viruses and other viral, bacterial and fungal agents, the WHO statement said.

PAHO said Saturday that it was informed by the Argentine Ministry of Health that the cause was Legionella and that additional authorities are now investigating the source.

The ministry is “collecting environmental samples, conducting risk assessments and implementing actions in the health clinic related to the outbreak,” the update said. “PAHO is providing support to Argentine health authorities from its headquarters and PAHO’s national office in Argentina to investigate and characterize the outbreak.”

The WHO statement states: “Sporadic outbreaks of Legionella pneumonia have already been reported in Argentina. Strong surveillance activities are underway in the affected health facility. However, in the absence of an identified source of Legionella bacteria, the risk of developing Legionellosis for people working or admitted to the same health facility is currently moderate. ”

In its statement, WHO recommends continuing laboratory tests and investigations into the outbreak, but does not recommend other specific measures for travelers or travel or trade restrictions based on current information available.

Legionnaires’ disease is a severe type of pneumonia caused by Legionella bacteria. People can get sick when they breathe in small droplets of water containing the bacteria, causing a lung infection. The disease can be treated with antibiotics.

Bacteria can be found in shower heads and faucets, whirlpools, cooling towers, hot water tanks, decorative fountains, or plumbing systems in large buildings.

San Miguel de Tucumán is the capital of the agricultural province of Tucumán, in northwestern Argentina.