The Ministry of Health and Social Protection, in coordination with the National Institute of Health (INS), informs the public that, as anticipated in the communication of December 18, the detection of the influenza A(H3N2) virus, subclade K (J.2.4.1), was confirmed in Colombia, in an imported case with a history of international travel to the United States.
The case involves an individual who presented with mild respiratory symptoms, such as fever, runny nose, and cough, and who reported recent travel on a cruise departing from Miami. Initial identification was made by the Genomics Group of Antioquia and subsequently confirmed by the Virology Group of the Directorate of Public Health Networks and the Genomics of Emerging Microorganisms Group of the Directorate of Public Health Research at the National Institute of Health (INS) through whole-genome sequencing (NGS).
To date, there has been no increase in the incidence of acute respiratory infections, nor in the severity of cases, hospitalizations, or deaths associated with this subclade of the virus in the country. Based on available evidence, the influenza vaccine continues to be effective in preventing serious complications, hospitalizations, and deaths.
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The Ministry of Health and Social Protection calls on citizens to maintain self-care measures:
These measures include frequent handwashing, especially upon arriving home, before eating, and after coughing or sneezing; adequate ventilation of enclosed spaces such as schools, public transport, health institutions, and care centers; the use of face masks by people with respiratory symptoms, especially when in contact with vulnerable populations, such as children, the elderly, or immunocompromised individuals; remaining in isolation for a minimum of 3 days when respiratory symptoms appear; and avoiding sending sick children to kindergartens or schools.
Vaccination remains an effective protective measure. The influenza vaccine available in Colombia in 2025 contains the A/H3N2 strain, and despite the differences inherent to subclade K, its use is recommended, as vaccine effectiveness reduces hospitalizations and deaths from this disease. Vaccination is indicated for the following groups:
Child population aged 6 to 23 months
People over 60 years old
Pregnant women from week 14 of pregnancy onwards
Population with risk diagnoses aged 24 months and adults
Human talent in health
People with chronic illnesses such as asthma, COPD, cardiovascular, kidney, liver diseases, diabetes, obesity, cancer, HIV, or other conditions that compromise the immune system
Family members and cohabitants of children under 18 with cancer
The country has a strengthened epidemiological and laboratory surveillance system, which allows for the early detection of respiratory viruses and the timely implementation of control measures. The Ministry of Health and Social Protection will continue to transparently report any updates relevant to the country’s public health.