The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

The Flu (Influenza) – Symptoms, Treatments and Prevention

the flu

In This Article

The Flu (Influenza)

Each winter, millions of people suffer from seasonal flu.

The flu, or influenza, is a highly contagious viral infection that mainly affects the respiratory system.

It’s usually a seasonal illness, with yearly outbreaks killing hundreds of thousands of people around the world.

Though rare, completely new versions of the virus may infect people and spread quickly, resulting in pandemics (an infection that spreads throughout the world) with death tolls in the millions.

Symptoms of the flu include sudden onset fever, coughing, sneezing, a runny nose, and severe malaise, though it can also include vomiting, diarrhea and nausea.

Viruses have become somewhat of a hot topic this year due to the SARS-CoV-2/COVID-19 Pandemic.

Given all that is going on with the current pandemic and the collision of flu season, I figured it would be a good idea to lay out as much information as I can regarding Influenza, The Flu and what could possibly happen when the flu meets COVID-19.





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What Causes the Flu?

The illness referred to as “The Flu” is different from a common cold however, early physicians described influenza-like illnesses as being influenced by the cold. 

The word influenza wasn’t used to describe a disease until centuries later when an epidemic in Florence, Italy was called influenza di freddo, which translates to “cold influence”.

The term influenza became commonplace to describe the disease in the mid-1700s and it wasn't until the 1930's when scientists finally isolated the virus that causes the flu. 

Today, we now know that more than 100 different viruses (mostly coronaviruses) can cause a common-cold, but only influenza viruses cause the flu.

There are 4 primary types of influenza viruses:

  • Type A and B viruses cause the large seasonal outbreaks that we usually associate with “flu season”.
  • Type C influenza viruses usually cause milder respiratory symptoms and is rare.
  • Type D viruses infect cattle and isn't known to infect humans.

Type A flu viruses are also found in many different animals, including ducks, chickens, pigs, whales, horses, and seals whereas type B viruses only affect people.

Depending on the type proteins on the surface of the virus, we can further categorize them into subtypes, such as H1N1, H3N2, etc.

How Does the Flu Spread?

The first thing to understand is that influenza is constantly evolving.

This means it quickly goes through mutations that slightly alter its surface proteins (H) and (N) antigens.

And it's because of these rapid changes that acquiring immunity is difficult.

This is why getting sick or vaccinated with a flu shot doesn't ensure immunity.

That said, if you do get infected and your body does develop immunity – natural or acquired via vaccination – there's still a chance you'll fight it off better than if you never became infected.

There are also times when the virus can undergo major changes to its antigen surface proteins, which most people don't have immunity to, resulting in pandemics. Either way, the flu usually spreads from person to person.

It spreads when you come into contact with the stuff someone else sneezes or coughs up.

It spreads when you breathe in aerosols that an infected individual generates as they walk around.

You could also get it on your hands from objects like silverware, doorknobs, handles, television remotes, computer keyboards, and telephones.

The virus primarily enters your body when you touch your hands to your nose, eyes, or mouth.

This is why washing your hands can slow the spread. Similar to the SARS-CoV-2 virus that causes COVID-19, Influenza has an incubation period.

People who are carrying the virus are likely contagious from about a day before symptoms appear until about 5 days after they start.

What Factors Increase the Risk of the Flu?


There are many factors that can increase your risk of developing the flu or its complications.

I personally don't believe that “October Flu Season” is why people contract the flu.

It makes more sense to me that October is around the time when people start consuming more candy (Halloween), comfort foods (Thanksgiving), alcohol (Thanksgiving, Christmas and New Years) and our exercise and sleep routines begin to change dramatically with changes in the season and daylight.

All together, that's a perfect recipe for immune suppression and vulnerability to the increased circulation of viruses.

Ultimately the immune system is the major factor behind flu vulnerability.
Our understanding of the immune system has advanced far beyond the simplicity of the “Germ Theory” of disease, where all of our ills were blamed on intruding organisms.
Today, scientists understand that it's not simply organisms causing problems in the body, but the immune system of the host (the body that gets infected) that matters.
That said, here's a few of the leading risk factors associated with the flu:
  • Age. Seasonal influenza tends to target children 6 months to 5 years old, and adults 65 years old or older.
  • Living or working conditions. People who live or work in facilities with many other residents, such as nursing homes or military barracks, are more likely to develop the flu. People who are staying in the hospital are also at higher risk.
  • Race. Native American people may have an increased risk of influenza complications.
  • Weakened immune system due to chronic health conditions. Cancer treatments, anti-rejection drugs, long-term use of steroids, organ transplant, blood cancer, Diabetes, HIV/AIDS and Autoimmunity can all weaken your immune system. This can make it easier for you to catch the flu and may also increase your risk of developing complications.
  • Weakened immune system due to lifestyle factors. Poor lifestyle choices such as not getting adequate sleep, not exercising enough, poor blood sugar regulation and consumption of alcohol or other drugs can all contribute to a weakened immune system that makes you susceptible to the flu.
  • Chronic illnesses. Chronic conditions, including lung diseases such as asthma, diabetes, heart disease, nervous system diseases, metabolic disorders, an airway abnormality, and kidney, liver or blood disease, may increase your risk of influenza complications.
  • Nutritional Deficiencies. People who do not have adequate nutrient levels are not able to fight off infections as well as people who have adequate nutrient status.  Micronutrient deficiencies including vitamin C, D and mineral deficiencies such as zinc, iron, selenium can all play a role in immune function.
  • Obesity. People with a body mass index (BMI) of 40 or more have an increased risk of flu complications.

What are the Symptoms of the Flu?


The flu shares very similar symptoms of the common cold including a runny nose, sneezing and sore throat.

But colds usually develop slowly, whereas the flu tends to come on suddenly.

And although a cold can be a bother, you usually feel much worse with the flu.

Common signs and symptoms of influenza (the flu) include:

  • Fever
  • Aching muscles
  • Chills and sweats
  • Headache
  • Dry, persistent cough
  • Shortness of breath
  • Tiredness and weakness
  • Runny or stuffy nose
  • Sore throat
  • Eye pain
  • Vomiting and diarrhea, but this is more common in children than adults

COVID-19 and the flu have many signs and symptoms in common, including:

  • Fever
  • Cough
  • Shortness of breath or difficulty breathing
  • Tiredness
  • Sore throat
  • Runny or stuffy nose
  • Muscle aches
  • Headache
  • Nausea or vomiting, but this is more common in children than in adults

When should you see a doctor?

Most people who get the flu can treat themselves at home and often don't need to see a doctor.

The most important signs to be on the look out for include major disruptions in your vitals: breathing, bowel movements, body temperature, etc.

For adults, emergency signs and symptoms can include:

  • Difficulty breathing or shortness of breath
  • Chest pain
  • Ongoing dizziness
  • Seizures
  • Worsening of existing medical conditions
  • Severe weakness or muscle pain

Emergency signs and symptoms in children can include:

  • Difficulty breathing
  • Blue lips
  • Chest pain
  • Dehydration
  • Severe muscle pain
  • Seizures
  • Worsening of existing medical conditions

Keep in mind that when your body is fighting a virus, body temperature is supposed to elevate.

Optimal human body temperature is 98.6°F (37°C). But some studies have shown that the “normal” body temperature can range from 97°F (36.1°C) to 99°F (37.2°C).

And this leads us to flu treatments and prevention.

What are the Treatments of the Flu?


Of course, the Centers for Disease Control and Prevention (CDC) recommend annual flu vaccinations for everyone age 6 months or older.

I don't buy that noise.

The truth is, out of all the vaccines we have available, flu vaccination is “over promoted” and “over-hyped” according to researchers.

Based on a report from the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota, here’s three of the key findings:

During some influenza seasons vaccination offers substantially more protection for most of the population than being unvaccinated; however, influenza vaccine protection is markedly
lower than for most routinely recommended vaccines and is suboptimal.

A major barrier to the development of game-changing influenza vaccines is the perception that current vaccines are already highly effective in preventing influenza infection.

In an effort to reduce influenza morbidity and mortality, over the last three decades the ACIP [Advisory Committee on Immunization Practices] has expanded the populations recommended to receive influenza vaccine. These recommendations, however, often were based on professional judgment and not on scientifically sound data.

The Independent article also includes input from Tom Jefferson – a Cochrane Collaboration researcher – who is quoted as saying:

We have conducted four reviews since the late 1990s. We calculated that you need to vaccinate between 33 and 99 people to prevent one case of flu, depending on the match between the vaccine and the circulating strains of the virus. I want people held accountable for wasting taxpayer’s money on these vaccines. The reviews have been available for years and nothing has been done.


So how good is the flu vaccine at protecting against influenza?

Flip a coin.

In the not-too-distant past, the CDC and other public health institutes estimated that flu shots cut one’s risk of contracting flu by between 70 percent and 90 percent.

The more common claim is that the vaccine lowers one’s risk by an average of about 50 percent to 60 percent.

Everyone wishes the vaccines were more effective, but the science just isn’t there yet.

Medical Treatments for the Flu

If you have a severe infection or are at higher risk for complications, your doctor may prescribe an antiviral drug to treat the flu.

These drugs can include oseltamivir (Tamiflu), zanamivir (Relenza), peramivir (Rapivab) or baloxavir (Xofluza).

These drugs may shorten your illness by a day or so, but they don't come without recourse.

A group of unbiased medical experts at the US Cochrane Center re-analyzed data from 20 clinical trials like these, reporting their results in a 2009 BMJ article.

Their meta-analysis showed that there was no significant evidence that Tamiflu reduced influenza symptoms or complications – the only possible positive association was that Tamiflu might decrease the length of time people exhibited symptoms by a few hours.

Additionally, a 2007 scientific report suggests that Tamiflu is in fact exceedingly dangerous.

In the 6 years that Tamiflu was marketed in Japan, the Japanese Ministry of Health Labour and Welfare received 1377 reports of adverse reactions.

Approximately half of these reactions were serious neuropsychiatric cases, including delirium, convulsions, and encephalitis.

Eighty deaths were reported, and 71 were considered to be directly related to Tamiflu.

Two of the most alarming deaths were suicides by 14-year-old teens on Tamiflu.

Finally, a 2011 Japanese study found that those diagnosed with influenza had an almost six fold increased risk of deteriorating and dying within twelve hours of receiving Tamiflu.

Natural Treatments & Flu Prevention

First, recognize that we live in an ocean of viruses, microbes and organisms.

If you're not taking care of your body, these organisms will take the opportunity presented to them and cause harm.

When you understand that the preschool analogy of foreign invaders (germs) fighting your inner soldiers (immune system) has been rendered obsolete by our awareness of the microbiome (including the virome!), and the poetic reality that we are made up of the very organisms we thought that we were fighting…

Well, pharmaceutical medicine seems something like cutting off your nose to spite your face.

There are several immune support protocols that can be helpful for addressing a cold or flu naturally.

Here's a summary of various immune supporting nutrients, dosages and duration for anyone looking to address the Common Cold or Flu:

Vitamin A 

Vitamin A is absolutely critical to the immune system, supporting the production of everything from mucus to antibodies.  It’s role in the immune system gave it its reputation as “the anti-infective vitamin” in the early half of the twentieth century.

A study published in Viruses demonstrated that vitamin A supplementation can improve immune responses to vaccines when children are vitamin A and D-insufficient at baseline.

For optimal support, I would suggest 4,500 – 15,000 IU's/day for 1-3 weeks.

Vitamin C

Vitamin C promotes the formation of antibodies that bind to and destroy dangerous toxins, bacteria, and viruses in our bodies before they can wreak havoc. Vitamin C also promotes wound healing by stimulating the production of collagen.

According to the journal Nutrients, Vitamin C appears to be able to both prevent and treat respiratory and systemic infections. A clinical study published in the Journal of Manipulative and Physiological Therapeutics, found that megadoses of vitamin C prevented influenza symptoms before or after the appearance of symptoms. 

I would suggest 300-5000 mg's per day for 1-3 weeks.

Vitamin D

It is well established that vitamin D plays a significant role in immunity.

Observational studies report consistent associations between low levels of vitamin D and increased susceptibility to infections and chronic states of health. 

Furthermore, a systematic review of 25 different papers, published in the British Medical Journal, determined that vitamin D supplementation is safe and protected against acute respiratory tract infections overall. 

The amount of vitamin D you take should be based on your blood chemistry analysis. However, I'd suggest 2000 IU's/day to 50,000 IU's/day depending on your current level of health.


Most people don't realize this, but zinc deficiency results in decreases of cell-mediated immunity.

Zinc deficiencies are common because of low intakes of animal flesh, especially red meat (the richest common dietary source of zinc), and high intakes of whole grain cereal products and legumes rich in phytate and other indigestible zinc-binding or depleting proteins.

A paper published in the American Journal of Public Health found that Zinc intake was associated with resistance to H1N1 Influenza.

I would suggest 5 mg to 20 mg/day for optimal health.


The Chinese have valued astragalus for centuries for its immune-enhancing properties. Studies have reported that astragalus promotes healthy growth of cells in damaged in the lungs after a viral infection.

Astragalus not only has been found to improve resistance to the common cold and anti-influenza activity, but may also decrease how long you stay sick.

The dosage recommended can range from 250 mg/day to 750 mg/day.


Extracts of Echinacea have been used traditionally in North America for the control of symptoms of colds, influenza, and other diseases, and some of them have become very popular as “herbal medicines”.

According to a study published in the Virology Journal, Echinacea extract inhibited the infectiousness of all examined flu viruses by over 99%.

I would suggest taking 100 – 400 mg/day for 1-3 weeks.


Andrographis has been mostly studied for the treatment of colds, flu, and upper respiratory infections. Lab studies suggest possible anticancer effects, but this has not been confirmed in humans.

In India, andrographis was widely credited for arresting the 1919 Indian flu epidemic. A systematic review published in 2004 found that Andrographis was superior to placebo in alleviating the symptoms associated with upper respiratory tract infections. 

Dosages can range from 200 – 1000 mg's/day for 1 – 3 weeks.

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