Flu symptoms are lingering for more than usual, warns expert

Amid scare of COVID due to the new variant XBB 1.16, infection due to H3N2 virus is picking up pace. State governments and governments of the union territories have been asked to remain alert on the rising cases of infection.


The infection has claimed nine lives in the country so far and going with media reports, the number of active cases is more than 450.


Though it is a seasonal influenza and the symptoms seem to be mild in nature, H3N2 influenza symptoms linger for longer duration, health experts have said.


We spoke to Dr.Nidhin Mohan, Consultant - Internal Medicine, Narayana Health City, Bengaluru on the symptoms and duration of the symptoms and what people need to do to stay safe.

The H3N2 virus was first detected in people in July 2011. It was identified in pigs a year before in 2010.


"During 2012, there were multiple outbreaks of H3N2v resulting in 309 reported cases. Sporadic infections with H3N2v have continued to be detected since that time," the US CDC says.


On how severe the virus is, Dr Mohan says, "H3N2 is a mutant form of influenza virus and immunity to this virus is less among the general population compared to normal influenza."

Dr Mohan says the symptoms are similar to influenza like fever, cold, cough, sore throat and body pain but they are more severe.


A four year old kid who was detected with this viral infection recently had a cough, cold, fever and signs of pneumonia three days before she was admitted to hospital.

"Symptoms typically last close to 7 days," says Dr Mohan and adds that in people with diabetes, asthma and those who are aged the symptoms may be prolonged for weeks and these people may need hospitalisation, in about 1 percent of cases.


"Cough and generalised tenderness may linger for a long time," says Dr Mohan.

"Precautions include vaccination every year with flu vaccine, maintaining social distance, hand hygiene, and using masks in crowded places, there is no need to panic, monitor for symptoms like breathlessness, or severe fatigue, especially in elderly, diabetic, asthmatic patients and visit a nearby doctor, most patients can be treated on OPD basis, very few need admission," explains Dr Mohan.


Staying safe is the key to avoid developing serious complications due to H3N2.

Though H3N2 symptoms appear to be mild in nature, they can have serious effects on health and also pose greater risk to old people and kids below the age of 5.


As per a recent media report, doctors in Pune are concerned over a sudden rise in the number of children below the age of 5 getting admitted in the intensive care units (ICUs). In Pune, a total of 428 samples have come positive for H3N2. "Studies conducted by CDC and others have indicated that children born after 2001 (age ≤9 years at 2010) have little to no immunity against H3N2v viruses. Adults seem to have more immunity, perhaps because they might have been previously exposed to similar viruses in their lifetimes," the US CDC explains.


The viral infection can also have severe complications in older people and those who have pre-existing health issues.

​H3N2 spurt: As cases rise, know who are in the high risk groups (and the symptoms seen during infection)​