Influenza Virus H3N2

As the flu season approaches, it’s important to stay informed about the latest developments in the influenza virus H3N2. This year, the H3N2 strain is the most prevalent form of the flu virus.

This strain has a reputation for being particularly virulent, and it can cause severe illness and even death in some cases.

Here are the most recent updates on the H3N2 strain of the influenza virus, including its symptoms, transmission, prevention and treatment.

Symptoms of H3N2

The symptoms of Influenza Virus H3N2 are similar to those of other flu viruses. They can range from mild to severe, and they can include:

Fever

Cough

Sore throat

Runny or stuffy nose

Body aches

Headaches

Fatigue

In some cases, people with Influenza Virus H3N2 may also experience vomiting and diarrhea, although these symptoms are more common in children than in adults.

It’s important to note that not everyone with H3N2 will experience all of these symptoms, and some people may experience few of these symptoms at all.

The symptoms of Influenza Virus H3N2 typically appear within 1-3 days after exposure to the virus also known as its incubation period and can last for up to a week or more.

If you think you may have H3N2 or any other flu virus, it’s important to seek medical attention right away and follow your doctor’s instructions for treatment and care.

Diagnosis

Specimen:

• Nasopharyngeal secretions
• Nasal washings
• Throat swabs

Antigen detection:

Rapid influenza diagnostic tests (RIDT): Immunochromatographic test (ICT) with 100% specificity and 50-70% sensitivity.

How influenza virus H3N2 spreads?

H3N2 primarily spread through droplets of respiratory secretions, which are released into the air when an infected person talks, coughs or sneezes.

These droplets can then be inhaled by other people who are nearby or can land on surfaces, where they can remain infectious for several hours.

Person-person transmission through contaminated hands and fomites also possible to contract H3N2. It can be by touching a surface contaminated with the virus and then touching your mouth, nose or eyes.

However, this is less common than respiratory transmission.

It’s important to practice good respiratory hygiene and hand hygiene to prevent the spread of H3N2 and other flu viruses.

This includes covering your mouth and nose with a tissue or your elbow when you cough or sneeze, washing your hands frequently with soap and water, and avoiding close contact with people who are sick.

Who are at higher risk of developing complications in H3N2?

Anyone can contract Influenza Virus H3N2, but certain groups of people are at higher risk of developing severe illness or complications. These include:

1. Children under the age of 5, especially those under the age of 2
2. Adults over the age of 65
3. Pregnant women
4. Obesity
5. People with weakened immune systems
6. People with chronic medical conditions, such as asthma, diabetes and heart disease
7. Chronic metabolic/ neurologic diseases
8. Comorbidities: chronic lung, liver, heart, kidney diseases

If you are in one of these high-risk groups, it’s especially important to take steps to prevent the spread of H3N2 and to seek medical attention right away if you develop any flu-like symptoms.

Complications

Respiratory complications (most common complication):

1. Pneumonia (m/c): Influenza Virus, secondary bacterial infection (Staphylococcus, S.pyogens)
2. Otitis media
3. Croup
4. Myositis (most common extra complication)

• Cardiac: myocarditis, pericarditis
• CNS: encephalitis

Current prevalence and severity of H3N2

The prevalence and severity of Influenza Virus H3N2 varies from year to year, depending on a variety of factors, including the effectiveness of the flu vaccine and the level of immunity in the population.

According to the Centers for Disease Control and Prevention (CDC), H3N2 has been the dominant strain of the flu virus in recent years, and it has been associated with more severe illness and higher rates of hospitalization and death than other strains.

While the severity of the illness varied widely, H3N2 was associated with a higher rate of hospitalization and death among other strains. It’s important to note that the prevalence and severity of H3N2 can vary from year to year, and it’s difficult to predict exactly how the virus will behave in any given flu season.

However, based on recent trends, it’s likely that H3N2 will continue to be a significant public health concern this flu season.

Vaccination options for H3N2

The best way to prevent Influenza Virus H3N2 and other flu viruses is to get vaccinated. The flu vaccine is typically available and it’s recommended for everyone over the age of 6 months.

Vaccines against influenza are administered annually because of their short-lasting immunity (6-12 months).

The flu vaccine is designed to protect against the circulating strains of type A viruses (H1N1 and H3N2) and one type B virus that are expected to be most prevalent in a given flu season. This year, the flu vaccine will include protection against H3N2, as well as other strains of the virus.

Trivalent / quadrivalent vaccine: Cold adapted live-attenuated strains: administered as intranasal spray.

It’s important to note that the flu vaccine is not 100% effective, and it may not prevent all cases of the flu. However, even if you do contract the flu after getting vaccinated, the vaccine still provide some protection and may reduce the severity of your illness.

Treatment for Influenza Virus H3N2

If you do develop H3N2 or any other flu virus there are several treatment options available, mainly is symptomatic treatment. Treatment include antiviral medications for severe influenza or people at risk for complications which can help to reduce the severity and duration of your illness.

Antiviral medications work best when they are started within 48 hours of the onset of symptoms, so it’s important to seek medical attention right away if you think you may have the flu.

NA inhibitors: prevent the release of the virus, effective against influenza A and B virus. It is given for 5-7 days

• Oseltamivir
• Zanamavir
• Peramivir

In addition to antiviral medications, it’s important to get plenty of rest, drink plenty of fluids and take over-the-counter medications to relieve your symptoms. If you are at high risk of complications from the flu, your doctor may recommend additional treatments or hospitalization.

Prevention tips for H3N2

In addition to getting vaccinated, there are several other steps you can take to prevent the spread of H3N2 and other flu viruses. These include:

1. Practicing good respiratory hygiene, such as covering your mouth and nose when you cough or sneeze
2. Washing your hands frequently with soap and water
3. Avoid close contact with people who are sick
4. Stay home from work or school if you are sick
5. Cleaning and disinfecting frequently touched surfaces, such as doorknobs and countertops

By taking these steps, you can help to protect yourself and others from the flu virus.

What to do if you think you have H3N2?

If you think you may have H3N2 or any other flu virus, it’s important to seek medical attention right away. Your doctor can perform a flu test to confirm your diagnosis and recommend the appropriate treatment.

In the meantime, it’s important to stay home from work or school and avoid close contact with others to prevent the spread of the virus. Make sure to get plenty of rest, drink plenty of fluids and take over-the-counter medications to relieve your symptoms.

Final thoughts on staying safe during flu season

The H3N2 strain of the influenza virus can cause severe illness and even death in some cases, so it’s important to take steps to protect yourself and others during flu season.

This includes getting vaccinated, practicing good respiratory and hand hygiene, and seeking medical attention right away if you develop flu-like symptoms.

By staying informed about the latest updates on H3N2 and other flu viruses, you can take the necessary steps to stay healthy and safe during the flu season.

Remember to take care of yourself and those around you, and together, we can help to prevent the spread of the flu virus.