Lately, there has been recurrent news in the media about the rising cases of the H3N2 virus. It appears to be affecting a significant portion of the population. The usual symptoms of H3N2- include prolonged cough, sneezing, weakness, pain in the ear and breathlessness. 

News started flooding in about this respiratory viral infection during January 2023 and new updates have been consistently coming in from time to time about the spread of the virus in India. On 6th March, Karnataka reported India’s first death from the H3N2 virus and that we are still hearing similar news.

Is the H3N2 virus dangerous? How can you detect this H3N2 influenza virus and stay protected? We have all the information you need.

So, let’s get started!

Symptoms of H3N2 infection

Prevention and treatment are linked to the quick detection of disease and that’s why it’s important to familiarise yourself with the symptoms of H3N2 influenza.

Some common symptoms seen in H3N2 seasonal infection are below:

• Fever (mostly with chills)
• Cough (which may even persist for 2-3 weeks)
• Muscle and joint pain
• Feeling unwell (acute malaise)
• Runny nose
• Sore throat
• Headache
• Nausea
• Abdominal discomfort/ pain
• Diarrhoea
• Itching or pain in ears
• Swollen lymph nodes (in children)

In H3N2 influenza viral infection, the cough can be quite severe, lasting for up to two weeks. Although most people do recover from the fever within a week without needing hospitalisations, H3N2 influenza can cause serious illness and can possibly be dangerous for certain high-risk patients. That is why it is very crucial to monitor the patient and seek expert help if the symptoms don’t recede or seem to get worse. 

Hospitalisation may be needed for high-risk groups. So this is something to keep in mind if someone in your household with comorbidities such as asthma, COPD, obesity, heart or lung disorders is diagnosed with this infection. 

Risk factors of H3N2 infection

Certain high-risk groups are more vulnerable than others. If you or your loved ones are in such groups, exercising caution is suggested:

• Pregnant women
• Children below five years
• Elderly individuals
• People suffering from chronic medical conditions (pulmonary, chronic cardiac, renal, metabolic, liver, hematologic and neurodevelopmental conditions.)
• Individuals undergoing steroid- therapy, chemotherapy and/or suffering from immunosuppressive conditions such as AIDS/HIV.
• Healthcare workers who are always exposed to patients and are at a greater risk of spreading it to vulnerable individuals.

H3N2 – mode of spread 

1. Person -to – Person transmission by respiratory droplets-

The H3N2 influenza virus spreads quite rapidly, especially in highly congested areas such as nursing homes, offices, public transport and schools. 

When the infected individual sneezes or coughs, the droplets containing the virus are released into the air; once it is airborne, the virus spreads up to a metre and infects those who are in proximity and breathe in the droplets quite easily. 

2. The virus can also spread due to physical contact. 

3. If you touch a contaminated surface or object, you may contract the infection. 

Diagnosis & treatment

Diagnosis of H3N2 influenza

The majority of H3N2 influenza cases are diagnosed clinically, but during periods of low activity, the infection of other respiratory viruses, such as Covid, respiratory syncytial virus, rhinovirus and adenovirus, can also present themselves as influenza-like illness, which makes clinically differentiating H3N2 influenza from other environmental pathogens a tricky matter,

In order to determine the nature of the pathogen, a respiratory sample along with a laboratory diagnostic test application will be necessary. 

Tests that may be advised by your doctor-

1. Routine blood and urine tests as needed
2. Real-time RT-PCR – Nasal or throat swabs 
3. Culture test for H2N3 virus
4. Antibody testing for the H3N2 virus

You can also book all the relevant tests together as a test package for the diagnosis of your fever.

Treatment of H3N2 Influenza

• Consult a doctor for diagnosis and treatment if you feel unwell. If a doctor suspects H3N2, you may be asked to monitor your temperature and vitals at home. 
• Maintain good hydration and nutrition.
• Warm saline gargles and steam inhalation can help soothe ear and throat discomfort along with cough.
• Follow the treatment prescribed by a doctor and do not self-medicate or start anti-viral medicines on your own, as these may have side effects. Your doctor will prescribe anti-viral medicines when deemed necessary. 
• In case of persistent high-grade fever, difficulty in breathing or fall in SpO2 below 94, seek medical help immediately.

Precautions for transmission prevention

Do’s

• Follow respiratory etiquettes – People (irrespective of whether being infected or not) should cover their nose and mouth with a tissue or handkerchief at the time of coughing or sneezing. Wear masks when stepping outside.
• Follow hand hygiene– Individuals should also wash their hands thoroughly with soap and water.
• Isolate yourself in case you are feeling feverish or unwell.
• To safeguard yourself, get yourself vaccinated annually. 
• Avoid crowded places as much as possible.

Don’ts

• Do not touch your nose, mouth or eyes, especially when travelling.
• Refrain from coming in proximity to those who are ill.
• Self-medicate 

Conclusion

Seasonal influenza, like the H3N2 virus, can be difficult to contain, especially in highly populated regions, unless good respiratory hygiene is maintained by the civilians at all times. To minimise your chances of an infection, get yourself vaccinated every year to keep the efficacy of the vaccine at optimal levels. Spreading awareness of the do’s and don’ts amongst your loved ones, friends and workplace or educational institute will also help protect other people from getting infected.

Disclaimer: The information included on this site is for educational purposes only and is not intended to be a substitute for medical treatment by a healthcare professional. Because of unique individual needs, the reader should consult their physician to determine the appropriateness of the information for the reader’s situation.

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