Measles in the city of Buenos Aires
Four cases reported in CABA
On February 1, 2025, the Ministry of Health of the Nation issued an epidemiological alert due to the confirmation of a case of measles in a six-year-old girl with residence in commune 14 of the Autonomous City of Buenos Aires (CABA) and a history of travel with her family group from Russia with stops in Vietnam, Dubai and Rio de Janeiro.
On January 29, the 20-month-old sister presented with fever, adding rash 5 days later. In neither case was it possible to verify the history of vaccination against measles and in both cases positive IgM for measles was detected in serum and measles viral genome by RTqPCR in urine.
On February 14, a third case of measles was confirmed in a 40-year-old adult with no travel history, residing in commune 14, close to the two previously confirmed cases. On February 10, the patient began with cough, adding fever and rash on February 12.
She reported complete vaccination. Serum IgM against measles was negative and IgG positive, and viral genome of the measles virus was detected by RTqPCR in urine.
On February 21, a fourth case of measles was confirmed in an 18-year-old adolescent, resident of CABA and with no travel history, residing close to the previous cases.
She began with fever on February 19, and on February 21, conjunctivitis was added. Given these symptoms, in addition to the epidemiological history of probable contact with confirmed cases, samples were taken that same day, confirming the diagnosis. The patient is under clinical follow-up on an outpatient basis. Complete vaccination is recorded in the medical history of the jurisdiction.
With the exception of the second case that required hospitalization for pneumonia, the cases were managed as outpatients. All of them are currently showing favorable evolution.
Three cases were confirmed in the INEI-ANLIS National Reference Laboratory “Carlos G. Malbrán” with identification of the genotype B3 lineage MVs/Buenos Aires.ARG/5.25. In the fourth case, the sample has already been referred for processing.
The Ministry of Health of the CABA proceeded to identify transmission scenarios and contacts for each of the three confirmed cases. Control actions by the different jurisdictions involved according to the residence of the contacts included: clinical follow-up, search for susceptible individuals, vaccination actions or indication of gammaglobulin, as appropriate. The epidemiological investigation and the corresponding control actions continue to be monitored.