As autumn rolls in, so does the familiar concern over the flu, specifically influenza A.
Here’s a look at this virus, specifically on how it gets transmitted, its symptoms, and why it remains a significant concern for public health.
What is influenza A?
Influenza A is a highly contagious virus that causes the flu, a respiratory illness affecting millions of people worldwide each year. It’s one of the most common and severe types of influenza viruses, which infects not only humans but also animals like birds and pigs.
Known for its ability to mutate quickly, influenza A can lead to regular seasonal flu outbreaks and occasionally global pandemics when new and highly infectious strains emerge.
How does influenza A mutate?
The structure of the Influenza A virus allows it to change over time through two processes:
- Antigenic drift. This refers to small and gradual changes in the virus’s surface proteins. These minor changes happen continuously, making the virus slightly different each season. Because of this, flu vaccines need to be updated every year to match the latest circulating strains.
- Antigenic shift. This is a more sudden and drastic change that creates an entirely new strain of the virus. When this happens, most people have little to no immunity to the new virus, which can lead to a pandemic. This is rare but can have serious global health impacts.
How is influenza A transmitted?
The influenza A virus spreads easily from person to person through the following methods:
- Through the air from coughs or sneezes. When an infected person coughs or sneezes, they release tiny respiratory droplets into the air, which you may inhale.
- By touching surfaces contaminated with the virus. The virus can survive on surfaces for a period, so touching objects like doorknobs, handrails, or phones contaminated with these droplets can lead to infection. If you touch a contaminated surface and then touch your mouth, nose, or eyes, the virus can enter your body and cause illness.
- Through close personal contact with infected individuals. Close contact, such as handshakes, hugs, or even being near someone with the flu, can spread the virus.
What are the symptoms of influenza A?
If you have influenza A, there’s a possibility that your symptoms may range from mild to severe. Here’s what to watch for:
- Fever or feeling feverish with chills
- Persistent, often dry cough
- Sore throat that ranges from mild to intense
- Runny or stuffy nose, especially in children
- Muscle or body aches
- Intense headaches
- Long-lasting fatigue
What are the types of Influenza A viruses?
Influenza A viruses are classified based on two proteins found on their surface: Hemagglutinin (H) and Neuraminidase (N).
Different combinations of these proteins give rise to various subtypes, some of which significantly impact human health. Here’s an overview of the most notable types:
- H1N1. The H1N1 subtype gained worldwide attention during the 2009 flu pandemic. This strain was highly contagious and spread quickly across countries, which resulted in millions of cases and heightened awareness of flu preparedness.
- H3N2. As another prominent Influenza A subtype, H3N2 tends to cause severe flu outbreaks. It’s often associated with higher rates of complications and hospitalizations, especially among older adults and those with weakened immune systems.
- Avian subtypes, such as H5N1 and H7N9. While these primarily infect bird populations, they pose a risk to humans as well. In rare cases, these avian flu viruses can transmit to humans, which often results in severe illness. Because these strains aren’t common in people, they can be harder to control.
How can you prevent influenza A?
Here are different ways best protect yourself and others from getting influenza A, especially during flu season:
- Annual vaccination for everyone aged 6 months and older
- Regular hand washing with soap and water for at least 20 seconds
- Avoiding close contact with sick individuals
- Wearing masks in crowded places during flu season
How do you treat influenza A?
If you’re diagnosed with influenza A, here are several treatments that can help manage symptoms and speed up recovery:
- Antiviral medications, like oseltamivir or zanamivir. Antiviral drugs, such as oseltamivir (Tamiflu) or zanamivir, are especially effective when taken soon after symptoms start. These medications can reduce the severity and duration of flu symptoms, which is particularly beneficial for those at higher risk, like older adults, young children and individuals with chronic health conditions.
- Supportive care, including rest and plenty of fluids. Rest is crucial for helping your body fight off the virus. Stay well-hydrated with water, herbal teas, or electrolyte drinks to recover faster and manage your symptoms.
- Over-the-counter medications. To ease discomfort, over-the-counter medications like acetaminophen or ibuprofen can help reduce fever and relieve body aches. These medications don’t cure the flu but can make symptoms more manageable.
Why is influenza A a concern for public health?
Influenza A poses significant public health challenges due to the following:
- Potential for severe illness or death, especially in high-risk groups. Influenza A can be particularly dangerous for the elderly, young children and those with chronic health conditions. In these populations, the virus can lead to serious complications, hospitalization, or even death.
- High mutation rate. The virus mutates rapidly, which means new strains emerge each year. This constant evolution requires regular updates to flu vaccines to ensure they protect against the most common and dangerous strains circulating each season.
- Risk of pandemics due to new and emerging strains. Influenza A has the potential to generate new and highly infectious strains that can lead to pandemics, which affect large populations worldwide.
How do you know if you have the flu or COVID-19?
Distinguishing between the flu and COVID-19 can be challenging due to overlapping symptoms. However, specific signs such as loss of taste or smell are more indicative of COVID-19.
To be safe, it’s recommended to take a rapid antigen test and learn about your infection status.
Frequently asked questions
What is influenza A and how does it differ from other flu viruses?
Influenza A is a highly contagious respiratory virus and a primary cause of seasonal flu epidemics. This virus differs from others in its ability to infect animals and humans, leading to more varied strains and higher mutation rates.
How is influenza A transmitted among individuals?
Transmission occurs mainly through droplets when an infected person coughs, sneezes, or talks. Individuals can also contract the virus by touching surfaces contaminated with the virus and then touching their face.
What are the common symptoms of Influenza A?
Symptoms include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, and fatigue. Some individuals may experience vomiting and diarrhea, though this is more common in children than adults.
Can influenza A be prevented, and what measures are effective?
Yes, vaccination is the most effective measure to prevent infection. Other preventive actions include frequent handwashing, avoiding close contact with sick individuals, and practicing good respiratory hygiene.
What treatments are available for Influenza A?
Treatment primarily involves rest, hydration, and over-the-counter medications to relieve symptoms. Antiviral drugs may be prescribed by healthcare providers to reduce severity and duration of the illness, especially in high-risk individuals.
Key takeaway
Influenza A is a highly contagious virus with the potential to cause seasonal flu outbreaks and, occasionally, global pandemics due to its rapid mutation rate. Understanding its symptoms, transmission methods, and prevention strategies—especially annual vaccination—are essential for reducing its impact.
If you have influenza A, early treatment and supportive care can help manage symptoms and speed up recovery.
To protect your health, check out this 3-in-1 rapid antigen test and distinguish whether your symptoms are caused by COVID-19, influenza A, or influenza B.
