The National Institute of Health issued an advisory on the prevention and control of seasonal influenza (H3N2) after 340,856 suspected cases were reported nationwide between epidemiological weeks 44 and 49.
The objective of this advisory is to alert and facilitate the health authorities and other stakeholders to ensure timely preventive and control measures, encompassing preparedness to deal with the increased workload expected in outpatient and inpatient departments during the next few months.
According to the advisory, influenza is an acute viral respiratory illness caused by influenza A and B viruses, leading to annual epidemics. Influenza A is associated with higher transmissibility and severe disease among older adults, young children, pregnant women, and individuals with chronic conditions.
During the 2025-2026 season, a new genetic subclade of Influenza A (H3N2), Subclade K, has emerged globally. Recently, there has been a rapid rise in the detection of H3N2 cases since August 2025 among different WHO regions.
The South-East Asia region has shown increased positivity of influenza cases, with a predominance of H3N2 (66% of all Influenza A cases) since May 2025 till the end of November. Similarly, Australia and New Zealand have also reported increased influenza cases, with a significant proportion of the H3N2 subclade.
Pakistan is also observing rising influenza-like illness (ILI) and severe acute respiratory infection (SARI) cases. The country has reported a total of 340,856 suspected ILI cases from epidemiological weeks 44 to 49 from all provinces and regions through the Integrated Disease Surveillance & Response System, with 12% positivity of H3N2 cases among tested samples.
According to the advisory, seasonal influenza viruses may present with mild symptoms but may progress to severe illness, particularly in high-risk individuals, including patients with chronic diseases (such as asthma, diabetes, cardiac and lung diseases), pregnant women, elderly people, and children under five years of age, who are at higher risk of developing severe or complicated disease.
Vaccination is the most effective way to prevent infection and severe outcomes caused by influenza viruses, particularly in high-risk groups. Influenza (seasonal flu) can spread from person to person through coughing or sneezing or through contaminated hands or other surfaces.
The advisory emphasised that if someone is sick or has been in close contact with persons having flu-like illness, the following preventive measures are recommended to limit influenza transmission:
Frequent and thorough hand washing with soap and water, and use of hand sanitizer when away from hand-washing facilities
Covering the mouth and nose while sneezing or coughing
Sick patients should take rest and avoid crowds
Taking social distancing measures
It is highlighted that the Public Health Emergency Operations Center (PHEOC) at CDC-NIH is regularly monitoring the flu situation.
Keeping in view the recent upsurge of influenza across various regions, the remarkable increase of H3N2 cases, limited access to healthcare services, unsatisfactory infection prevention and control practices in different settings, and limited health awareness in the community, the flu season in Pakistan can be severe.
Therefore, it is essential for individuals, especially those in high-risk groups, to take preventive measures, such as getting vaccinated, practicing good hygiene, and seeking medical attention promptly if symptoms persist.
The objective of this advisory is to alert and facilitate the health authorities and other stakeholders to ensure timely preventive and control measures, encompassing preparedness to deal with the increased workload expected in outpatient and inpatient departments during the next few months.