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The Ministry of Health has been asked to be alert to the increase in influenza A cases subclade K which is known as super flu. This is because this new variant is “more aggressive, so it spreads more quickly and causes more severe symptoms—especially in the elderly, children and people with comorbid diseases.”
Previously, the Ministry of Health said that by the end of December 2025, there would be 62 cases of influenza A recorded subclade K is spread across eight provinces, with the largest numbers in East Java, South Kalimantan and West Java. The majority of cases occur in women and children age groups.
Globally, an increase in influenza A (H3N2) cases has been observed in the United States since the end of September 2025, as winter has entered.
Subclade K was first detected by Center for Disease Control and Prevention (CDC) USA in August 2025 and has now reportedly spread to more than 80 countries.
What is super flu?
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The term “super flu” is actually unknown in medical terminology. This name is popularly used as a general name to describe a variant of the influenza virus that is aggressive, spreads easily, and causes more severe symptoms.
Scientifically, the virus nicknamed “super flu” was identified as influenza type A subvariant H3N2 with subclade K. Subclade K is a new variant first identified by Center for Disease Control and Prevention (CDC) United States in August 2025.
The United States CDC recorded that as of December 20 2025, at least 7.5 million people were infected with influenza. Of that number, around 81,000 patients had to undergo hospital treatment, while more than 3,100 people were reported to have died.
A number of US states currently have very high influenza prevalence, including Colorado, Louisiana, New Jersey, New York and South Carolina.
The US also reported that all key monitoring indicators showed an increasing trend, starting from laboratory test results, outpatient visits, hospitalization rates, to deaths.
This spike in cases is said to be driven by the dominance of the H3NA subvariant type A influenza virus with subclade K.
How many super flu cases are there in Indonesia?
So far more than 80 countries have reported cases of “super flu”. In the Asian region, the new influenza variant has also been detected in a number of countries such as China, South Korea, Japan, Singapore and Thailand since July 2025.
Despite being the dominant variant, the trend of cases in these countries has shown a decline in the last two months.
In Indonesia, the Ministry of Health’s inspection results show that “super flu” has been detected since August 2025.
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Based on the results of the examination whole genome sequencing (WGS) until the end of December 2025, 62 cases of influenza A were recorded subclade K is found in eight provinces.
The three provinces with the highest number of cases include East Java, South Kalimantan and West Java.
The Director of Infectious Diseases at the Ministry of Health, Prima Yosephine, in a press release stated that the majority of cases were found in women and the child age group.
Of the 843 influenza positive specimens, 348 samples underwent WGS examination. All variants detected are known variants and circulate globally.
Nevertheless, Prima claims that the “super flu” situation is still under control and does not show any severity compared to other variants.
“Based on WHO assessment and available epidemiological data, influenza A type H3N2 subclade K did not show an increase in severity. “The symptoms that appear are generally similar to seasonal flu, such as fever, cough, runny nose, headache and sore throat,” said Prima.
What are the symptoms of super flu and can it cause death?
Persahabatan Hospital lung specialist, Agus Dwi Susanto, is somewhat doubtful of the Ministry of Health’s findings regarding the number of “super flu” cases in Indonesia.
Because, if it is discovered that they have been detected entering Indonesia since August 2025, then the figure should be more than what is recorded now.
“Just try using percentages, 62 cases out of just 842 specimens examined. Imagine how many thousands of influenza cases there were from August to December? This means that it could actually be more,” he told BBC News Indonesia, Friday (02/01).
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Chairman of the Honorary Council of the Indonesian Lung Doctors Association (PDPI), Tjandra Yoga Aditama, also has the same opinion.
He said he was not so sure that the number of “super flu” cases in Indonesia was 62, considering that in countries such as Thailand, Malaysia and Japan, there had been a “high increase in cases”.
This global pattern, he said, should also apply in Indonesia.
“So, I’m not really sure, it’s only 62. If possible, the genomic surveillance will be expanded, so that we know whether there is a lot of H3N2 now or not. Then there’s symptom surveillance, which means looking to see if there is an increase in influenza visits to polyclinics, especially if they go to the hospital,” he explained.
But apart from that, Agus Dwi Susanto, said there are several symptoms of “super flu” that you should be wary of because this new variant has more severe symptoms than seasonal influenza in general.
Namely, a high fever between 39 and 41 degrees Celsius.
“If so [influenza] usually 37-38.5 degrees Celsius,[[subclade K]it can be up to 41 degrees according to data. The meaning is really higher,” he explained.
“Then accompanied by severe muscle pain, very weak. Then a severe headache, sore throat and dry cough.”
“Maybe people often get the flu, right? You know what it feels like. Nah This level is more severe than what is usually experienced. “If you experience it, you need to be alert,” said Agus.
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In general, cases of regular seasonal influenza can pose a risk of death. Especially in vulnerable populations and in the presence of complications.
In the case of subclade K, Agus said the risk of death could be higher because of the nature of the variant subclade K is more aggressive and spreads more easily.
So the risk of complications resulting in death “can also be higher” in the elderly, children and people with comorbid diseases.
“So if it is more aggressive, the risk of death due to complications is higher. Especially in certain populations. Therefore, understanding the public is recognizing the symptoms,” said Agus.
“Usually the flu is just a runny nose, sore throat, mild. Now it’s a headache, muscle aches, high fever 39 to 41 degrees, continues to feel weak… well those are the symptoms subclade K,” he said.
What treatment should be done and what is the prevention?
However, people do not need to worry because influenza is generally a variant subclade This K can be cured, said Agus Dwi Susanto.
“The important thing is to immediately consult medical staff, a doctor or a health facility to receive treatment. Get enough rest, enough supplements,” he explained.
“For populations at risk who have underlying diseases, they may need to be treated. Because we have to take care of the complications so they don’t pose a higher risk.”
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“So the indications for treatment are basically like influenza in general. When is outpatient treatment, when is hospitalization, it’s the same,” he added.
“Of course as medical personnel we have to do more aware also, when does this need to be treated and when is it outpatient.”
Regarding prevention, one thing that can be done is the influenza vaccine.
Tjandra Yoga Aditama said the vaccine was made based on the old H3N2 subvariant, right? subclade K.
However, he said, several studies show that the vaccine is still effective in preventing transmission of “super flu”, although not as high as for H3N2.
The official recommendation from the World Health Organization, WHO, also states that the influenza vaccine can still be given.
“[Meskipun] “its effectiveness in children is only 70% and adults 40%,” said Tjandra Yoga.
“But because that’s what we have, please use it if you really want to,” he said.
Other prevention is to maintain a clean environment, wash your hands regularly, wear a mask when in contact with sufferers or in crowds.
Apart from that, if you are sick, you are advised not to leave the house and if you have to, wear a mask and immediately go to a health facility.
Tjandra Yoga also said that even though the spread was fast and aggressive, cases of “super flu” would not lead to a pandemic.
“Of course, if the mutation changes again, it will be a different story. But if the situation persists until now, then this is not heading towards a pandemic,” he said.
What are the steps taken by the Ministry of Health?
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Director of Infectious Diseases at the Ministry of Health, Prima Yosephine, said further monitoring of “super flu” would continue to be strengthened through surveillance, reporting and preparedness to respond to developments in the influenza situation in Indonesia and globally.
Monitoring is carried out for reports of influenza-like illnesses and severe acute respiratory infections in various health care facilities.
Regarding the Ministry of Health’s alleged weak monitoring, the spokesperson for the Ministry of Health, Aji Muhawarman, said that his party has a Public Health Emergency Operation Center which runs an Early Alert and Response System for diseases that have the potential to cause an outbreak.
The results of surveillance in the field, said Aji, are reported in stages and periodically from regional to central to anticipate disease incidents.
“Tightening is also carried out if there are observations that there is a potential for a spike in cases,” he said.