Respiratory illness and vaccination trends in Argentina

Argentina is experiencing a significant rise in respiratory illnesses and a simultaneous decline in immunization coverage. Health reports indicate that the country has recorded 992,803 cases of influenza-like illness (ILI) so far this year, the highest number recorded between 2016 and 2026.

As of October 2026, the National Epidemiological Bulletin reports that ILI cases have surpassed one million, marking a 3.3% increase compared to the same period in 2025. This rise is attributed to an earlier start to the respiratory virus season. While the circulation of respiratory viruses is currently on a downward trend following winter peaks, Influenza B is showing increased relative dominance, and respiratory syncytial virus (RSV) remains the predominant virus among hospitalized patients.

Cumulative cases of pneumonia have reached 127,046 for the year, while bronchiolitis in children under two years of age has reached 113,108 cumulative cases.

Compounding these health challenges, infectious disease specialists have warned that declining vaccination rates pose a risk to herd immunity. Immunization levels have reportedly dropped from approximately 90% before the pandemic to 70% following the pandemic, with some specific vaccines falling as low as 50%. Specialist Hugo Pizzi has noted that this decline creates conditions for preventable diseases to resurface. Health authorities have expressed particular concern regarding decreasing vaccination rates among children and adolescents in regions such as Misiones, citing measles as a critical warning sign.