NIH issues advisory for H3N2 influenza

ISLAMABAD:

The National Institute of Health (NIH) has issued an advisory on the prevention and control of Seasonal Influenza (H3N2) in view of a rising number of cases reported globally and within Pakistan.

The advisory aims to alert provincial health authorities and other relevant stakeholders to ensure timely preventive and control measures. It also calls for preparedness to manage an expected increase in patient load in outpatient and inpatient departments during the coming months.

According to NIH, influenza is an acute viral respiratory illness caused by Influenza A and B viruses and is responsible for annual epidemics worldwide. Influenza A is associated with higher transmissibility and more severe disease, particularly among older adults, young children, pregnant women, and individuals suffering from chronic conditions such as asthma, diabetes, and cardiac or lung diseases.

The advisory notes that during the 2025-2026 influenza season, a new genetic subclade of Influenza A(H3N2), known as Subclade K, has emerged globally. Since August 2025, a rapid increase in H3N2 cases has been reported across several World Health Organization (WHO) regions.

In the South-East Asia region, influenza positivity has increased significantly, with H3N2 accounting for 66 percent of all Influenza A cases reported between May and the end of November 2025.