On 30th August 2022 the Ministry of Health in Argentina informed the WHO/Pan American Health Organisation (PAHO) that it had been notified of the “detection of a cluster of 6 cases of bilateral pneumonia”. These cases, without “etiological identification so far” were observed by the Ministry of Public Health of Tucumán Province. 

The initial cases  

Each of the 6 cases was associated with the same health centre. The patients are 5 health workers and a patient, in the intensive care unit of a private clinic. The onset of symptoms was reported to be between the 18th and 22nd August. The patients presented with “fever, myalgia, abdominal pain, and dyspnoea”. They also presented with bilateral pneumonia. Unfortunately, 2 of the patients had died by the end of August; 3 were hospitalised and 1 was at home in isolation.  

Identifying the samples 

Samples were tested by the local public health laboratory for a range of respiratory viruses as well as viral, bacterial, and fundal agents. According to the PAHO report, “all tested negative”. Thus, the samples have been sent on to the National Administration of Laboratories and Health Institutes “Dr Carlos Malbrán” for further testing. This will include toxicological testing.  

Further cases 

On 1st September 2022 the Ministry of Public Health of Tucumán reported 3 additional patients. All of these are health workers. Their symptoms, similar to those presented by the other cases, began between 20th and 23rd August. Contacts of the cases are “under follow-up and to date none have developed symptoms”.  

As of 3rd September, a total of 11 cases of pneumonia, including 4 deaths, have been reported. They are all linked to the private clinic in San Miguel de Tucumán. According to the PAHO report 10 of the 11 presented “underlying or risk conditions”, the most frequent of which were “hypertension, smoking, and diabetes”. The report also states that the fatal cases had comorbidities.  

Possible Legionella  

On 3rd September 2022 the National Administration of Laboratories and Health Institutes reported that “amplification products of the 16S ribosomal gene from Legionella were sequenced from two bronchoalveolar lavage (BAL) samples”. The results, obtained by “massive sequencing” and “four bioinformatic analysis methods” were compatible with Legionella pneumophila. Further confirmation is required, alongside culture and seroconversion analysis. PAHO states that “Legionella, particularly L. pneumophila species, is associated with outbreaks of severe pneumonia.” transmission is common through inhalation of contaminated aerosols.  

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