‘No need to panic’: What you need to know about the ‘super flu’

Are you feeling under the weather and fearing that you might have the “super flu?” An infectious disease expert told Filipinos that there’s no need to panic.

“Super flu” is officially identified as subclade K, a mutated variant of influenza A that causes seasonal flu.

Subclade K was detected in at least 30 countries in 2025, according to the World Health Organization (WHO). Among the countries that saw an increase of subclade K cases are the United States, Australia, United Kingdom, and Canada.

“They call it ‘super flu’ because of the ability of this mutated H3N2 [subtype influenza A] to cause more infection or influenza-like illness in most countries,” Dr. Rontgene Solante told Rappler.

In the Philippines, the Department of Health (DOH) recorded 63 cases from January 1 to December 27 last year. All cases were reported to have recovered.

The DOH also noted that “current epidemiological data do not suggest an increase in disease severity among subclade K cases,” based on the WHO risk assessment as of December 2025.

Symptoms, detection

How would you know if you have the “super flu?”

Solante explained that the “super flu” has the same symptoms as a regular flu, making it difficult to tell if a person has a regular one or subclade K.

A person experiencing flu may suffer from cough, sore throat, headache, fatigue, chills, and fever.

“That’s [why it’s] very hard to tell whether the symptom is related to the non-mutated [or] the mutated H3N2, because based on the current data, there’s not much difference in the clinical symptoms,” the infectious disease expert said.

Solante stressed that severe and persistent symptoms do not automatically mean the person has the “super flu.”

“Even the seasonal flu that we have, there are patients na minsan umaabot ng two weeks, nagre-relapse na dahil nga hindi naman nagpapahinga, nagtatrabaho pa rin. Minsan, ‘yung iba, complicating into a bacterial infection na. ‘Pag tumatagal ng two weeks ‘yan, hindi ibig sabihin ‘super flu’ na ‘yan. So you need to rest, you need to take time for your infection to really heal,” he said.

(Even with the seasonal flu that we have, there are patients who remain sick for two weeks, relapsing because they do not rest, they continue to work. Sometimes, others experience bacterial infection. If the flu lasts for two weeks, that does not necessarily mean you have the super flu.)

The only way to determine if a person has the “super flu” is through a test conducted in the hospital, Solante said, adding that the doctor has the discretion to decide who should be tested.

“We usually do it, testing them, especially for those who are [part of the] vulnerable population. Ibig sabihin, itong may mga edad na, may mga (This means the elderly and those with) comorbidities,” Solante said. “So, meaning if you will be able to detect the presence of influenza in that particular patient, there is treatment that is highly effective to prevent complications.”

Treatment

Since “super flu” and a regular flu have the same symptoms, Solante said the treatment is also similar.

A person battling the flu may take an anti-viral drug as it is effective for both seasonal and “super flu.” Solante reminded the public to not take antibiotics to treat flu symptoms.

“You will be in danger of promoting antibiotic resistance,” he said.

To relieve the disease, the infectious disease expert also advised taking a rest and drinking lots of fluids.

In cases when symptoms are accompanied by difficulty in breathing, Solante said the person should consult a doctor for proper diagnosis.

Avoiding the flu

The DOH and Solante said vaccination would help in avoiding the flu, regardless if it is regular or the “super flu.”

“Vaccination is still expected to protect against severe illness and prevent hospitalization,” the DOH said.

“Even if it is mutated subclade K, the data is still telling us that the flu vaccine that we are using are still effective,” said Solante.

The doctor also encouraged people, especially high-risk individuals, to wear face masks particularly in crowded places as it is “one of the most important barriers” against the infection.

Washing hands is also advised because “​​surfaces can also be the source of contamination.”

Solante said the most important prevention is enhancing the immune system.

“You need to rest. You need to have…proper food, diet, and then less stressful environment or event,” he said.

Health Secretary Ted Herbosa earlier said the “super flu” in the Philippines is not alarming.

“I think the warning I will give is for Filipinos that will travel to the temperate countries, that will go to North America, to the UK. If you’re going there, be knowledgeable that there is a spread of super flu in that area. Maybe get the northern hemisphere vaccine, that’s my best advice for them,” Herbosa said in a briefing. – Rappler.com