Indonesia Steps Up Surveillance as ‘Super Flu’ Spreads Globally

Jakarta: As 2026 begins, Indonesia -,along with several other countries,- is facing the spread of a fast-moving strain of influenza A (H3N2), widely referred to as the “super flu.”

“Known scientifically as H3N2 subclade K, the variant has been linked to a recent rise in influenza cases across the United Kingdom, the United States, Australia, Japan, and parts of Europe,” quoted from Antara, Wednesday, 7 January 2026.

The World Health Organization (WHO) has reported a global increase in seasonal influenza activity in recent months, with a growing share of cases attributed to influenza A (H3N2). While overall activity remains within expected seasonal levels, several regions have experienced earlier-than-usual surges and higher transmission rates.

In Europe, subclade K was first detected in Norway before spreading to the United Kingdom, where the influenza season began four to five weeks earlier than normal, according to the Vaccine Alliance (Gavi).

In the United States, influenza activity was relatively low before Thanksgiving but accelerated sharply following holiday travel and school reopenings. The Centers for Disease Control and Prevention (CDC) has recorded at least 2.9 million infections, 30,000 hospitalizations, and 1,200 deaths so far this season, with H3N2—predominantly subclade K—accounting for most cases.

Australia has also reported an unusually prolonged flu season. Although influenza notifications have declined in recent weeks, H3N2 subclade K infections continued to appear toward the tail end of the season, which typically runs from May to October.

Indonesia Situation

In Indonesia, the Health Ministry recorded 62 confirmed cases of H3N2 subclade K across eight provinces by the end of 2025, with women and children comprising the majority of cases.

The data were obtained through whole genome sequencing (WGS) completed on December 25, 2025. The variant has been detected since August 2025 via the ILI-SARI sentinel surveillance system operating in healthcare facilities nationwide.

Influenza cases surged in early October, with positivity rates reaching 38 percent, largely driven by seasonal factors. Transmission typically increases during cooler temperatures and the rainy season.

The WHO has confirmed that current epidemiological evidence does not indicate increased disease severity associated with subclade K. Symptoms remain similar to seasonal influenza, including fever, cough, runny nose, headache, and sore throat. Nevertheless, the variant’s rapid spread warrants close monitoring.

Surveillance Strengthened

The Health Ministry said that as of late December 2025, Indonesia’s H3N2 subclade K situation remained under control, with no indication of heightened severity compared to other influenza strains.

However, the government has pledged to strengthen surveillance, reporting, and preparedness to anticipate potential changes in influenza transmission.

Enhanced monitoring will focus on case numbers, symptom severity, and transmission patterns, alongside ensuring health facilities are prepared for a possible rise in infections. Improved upstream detection through measurable surveillance systems is expected to support evidence-based policy decisions.

According to Prof. Masdalina Pane, a research professor in epidemiology and biostatistics at the National Research and Innovation Agency (BRIN), effective outbreak control depends heavily on optimizing the Early Warning and Response System.

“This system functions like a radar that monitors epidemiological thresholds,” she said, adding that strengthening surveillance at selected healthcare facilities is essential to maintain sensitive and accurate case detection.

Public Awareness and Vaccination

Authorities stressed that surveillance efforts must be accompanied by increased public awareness. The public is urged to maintain strong immune systems by practicing clean and healthy behaviors, including frequent handwashing, adequate rest, and balanced nutrition.

The Health Ministry also reaffirmed that existing influenza vaccines remain effective in reducing the risk of severe illness, hospitalization, and death caused by subclade K.

Early estimates published in Eurosurveillance suggest vaccine effectiveness of 72–75 percent among children and adolescents, and 32–39 percent among adults.

Annual influenza vaccination is therefore strongly recommended, particularly for vulnerable groups such as the elderly, pregnant women, and individuals with underlying health conditions.

To reduce transmission, people experiencing flu-like symptoms—including fever, coughing, fatigue, or body aches—are advised to limit contact with others, consider wearing a face covering, and take appropriate medication to manage symptoms.