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What Really Causes Influenza? Part 2

What Really Causes Influenza? Part 1

Written by Daniel Roytas (MHSc Human Nutrition), BHSc (Naturopathy), Dip. RM

In part 1 of this blog, an overview of some of the most important experiments conducted to try and prove that influenza was caused by a contagious virus were discussed in detail. Despite the most desperate attempts by scientists and doctors to make healthy people sick, every single attempt failed. Part 2 of this blog post aims to answer two questions. Firstly, what is the original proof showing that a virus causes influenza? Secondly, if not a virus, then what other plausible explanations are there?

It’s important to note that whilst a number of potential alternative causes of influenza will be discussed in this blog, these are only hypotheses and not claims.

The Discovery of Influenza

How did we get to the point where we “believe” that a virus causes influenza (or any infectious disease for matter)? An assumption was made, that a sick person was able to transmit a “germ” to a healthy person and make them sick. When scientists looked under the microscope of bodily fluids taken from a sick person, they saw bacteria present within the samples and assumed these were the cause of influenza. Yet when experiments failed to induce illness by exposing healthy people to bacteria, it was assumed there must be an even smaller microscopic particle responsible for the observed phenomena. This unknown, invisible microscopic particle was defined as a “virus”, a name given to a particle that had yet to be discovered. It’s important to note that to this very day, a “virus” has never been observed in, or isolated from the bodily fluids of a sick person or animal. Even more concerning is that a virus has never been exposed to a healthy host and shown to cause disease1,2. For more information about how a virus is “isolated” please refer to part 1 of this blog post.

How was the influenza virus first discovered and proven to cause illness? In 1933, Smith and Andrews published a paper claiming to have obtained an infectious virus from an influenza patient3. The methodology of this paper is as follows. Mucous was taken from one sick person and put through a filter to remove all impurities apart from the (assumed) “virus”. After many unsuccessful attempts to infect humans and animals like monkeys, rabbits, dogs, rats and mice, the filtered mucous was injected subcutaneously and sprayed into the nasal cavities of two ferrets. The ferrets had a rise in body temperature, watery eyes and nasal discharge. Not surprisingly, these symptoms were not replicated when they (Smith & Andrews) tried to infect other ferrets the same way. Some ferrets only had slight elevations in temperature, some had mild symptoms and no temperature, whilst others had no symptoms at all3.

Smith and Andrews concluded that these findings were proof of the existence of the influenza virus and the rest is history. How anyone can take this as proof of anything is remarkable in itself. The leaps in logic are questionable to say the least, especially when no other animal or human was ever able to be infected in hundreds of other experiments conducted by countless other researchers. How can some non-specific symptoms that occurred in a couple of ferrets after being injected with mucous and kept under unknown experimental conditions, provide any real insight in to the true nature of influenza?

If Not a Virus, What Causes Influenza?

Given that there is little rigorous scientific evidence proving that influenza is caused by a virus (see blog post 1 for more information), the next question that naturally comes to mind for most people is, what is the cause of influenza? It’s important that we don’t make presuppositions and invent new alternative unscientific explanations out of thin air as to the cause of influenza and other infectious diseases. Doing such a thing would simply be a repeat of precisely what scientists and doctors did 120 years ago when they assumed germs were the cause of disease. It’s not as simple as just making up an alternative explanation and running with it. The answer must be arrived at through the scientific method which involves the formulation of new hypotheses, the validation of these hypotheses through a series of rigorous, systematic and methodological experiments and the replication of these experiments by others.

Whilst it’s important not to jump to alternative conclusions, this is not to say that other viable hypotheses do not exist and should not be put forward and investigated further. Dozens of alternative potential causes have been postulated before and after the invention of the “germ theory”, however these have never been diligently investigated. Anyone who proposed an alternative perspective was either silenced or had their idea immediately quashed and labelled “conspiratorial” by dogmatic and fanatical supporters of the germ theory.

The reasons the true cause of influenza (and other infectious diseases) have never been investigated is two-fold. Firstly, the germ theory was forced upon a reluctant scientific and medical community to be accepted as fact, and then taught in colleges and universities by these doctors and scientists to naïve students, both of whom never questioned the validity of the supporting scientific evidence. Secondly, this “belief system” was propped up by the fear of reprisal for anyone who should question germ theory. Dissidents of the theory, had their names tarnished, and their careers and livelihoods threatened or destroyed. Whilst this fear of reprisal undoubtedly deterred most from challenging germ theory, many medical doctors and scientists have publicly challenged and voiced their concerns about the theory, but to no avail4,5.

Other Potential Causes of Influenza

In 1924 a paper published by the United States Public Health Service and Surgeon General proposed a number of alternative causes of the common cold and influenza6. The rapidity of the spread of influenza not only throughout communities, but between countries and entire continents, perplexed doctors and scientists at the time. It was apparent that the germ theory was not sufficient in explaining how influenza could arise almost simultaneously in cities hundreds and thousands of kilometres apart, especially during times when aeroplanes and automobiles did not exist. Quote “It (influenza) has travelled faster than the crow flies, yet who infected the Eskimos in the inaccessible far north, or the inhabitants of countries in the far south end of the globe at the same time as Europe and America?”. 

A number of meteorological, geological and environmental factors are discussed in the paper in an attempt to explain the sudden and simultaneous outbreaks observed around the world. These factors include atmospheric temperature changes, atmospheric pressure, wind, humidity, floods, comets, earthquakes, cyclones, anti-cyclones, atmospheric ozone dispersal, solar activity, miasmas, chemical poisoning, living conditions, bacteria, viruses & bed bugs6.

Interestingly, there is continued and considerable ongoing discussion in the recent scientific literature about some of the relationships between influenza and air temperature7, absolute or specific humidity8, high wind speed9, atmospheric & celestial phenomena10, solar activity11 and sick building syndrome12. One must ask the question why these factors are still being discussed in the literature when the cause of influenza has supposedly been known for almost 90 years3.

Ships at Sea

Another interesting discussion point questioning the nature of contagion in the review paper related to influenza outbreaks on ships mid-voyage6. These ships left ports where no influenza was known or prevalent at the time of departure and none of the crew members were ill on departure. These outbreaks would occur weeks or months after setting sail, long after the generally accepted incubation period had ended. The following are some quotes taken from this report;

Quote “Influenza attacked the crew of an East Indianian on the voyage from Malacca to Canton so generally that scarcely a single person escaped; when they left Malacca the disease was not prevalent there, but when they arrived at Canton it transpired that their outbreak on board in the China Sea had happened at the very time when the disease was showing itself with equal intensity at Canton”.

Quote “The statement that influenza will thus break out in the mid-sea, without there being any possibility of the disease having been introduced on board, is a most important piece of evidence, as it would prove that the atmosphere can not only carry the poison, but that no degree of dilution can destroy it without denying the occurrence of such outbreaks”.

Quote “The following is a report of a slight epidemic of influenza in Sitka, Alaska in 1924. Members of the crew of two or three fishing vessels informed me that their illness started while at sea and after they had been at sea for a week or longer”.

How is it possible that crew members fell ill with influenza more than a week after setting sail? This is a peculiar observation, especially given the fact that the CDC says “the time from when a person is exposed and infected with flu to when symptoms begin is about 2 days, but can range from 1 to 4 days”. Were the ships crew falling ill because of a virus somehow travelling hundreds of kilometres out to sea, or is it possible that atmospheric or environmental changes were to blame?


One interesting alternative explanation discussed in the 1924 paper lends credence to influenza being caused by changes in humidity and temperature. Quote “The injection of even a small a quantity as 6 c.c of pure distilled water into the blood produces a rise of body temperature which in some persons reaches 37.8⁰C (100⁰ F). Such a rise of body temperature quickly disappears on health and the temperature returns to normal. The explanation of this rapid rise of temperature is that the addition of even this small quantity of water to the blood increases the chemical changes that produce heat in the body. When a cool and moderately damp atmosphere becomes very damp one of its effects is that it causes a retention of water in the blood and tissues of the body, and consequently an increase in the chemical changes that produce heat in the body. When influenza is epidemic the explanation of the fact that some are immune and others suffer from the disease in different degrees of severity is afforded by the different proportions of water which are found in the blood and tissues of different individuals in health. All have not exactly the same proportion of water in their blood and tissues in health”6.

Whilst this explanation may seem far-fetched, you may be surprised to learn that a close relationship exists between humidity and influenza. A recent paper published in 2021 reported that humidity values are highly correlated with the onset of seasonal influenza. More specifically, it was found that there is a precise level of low humidity (specific for each region of the world) that may signal a flu outbreak is imminent8. This effect is so significant in fact, that government agencies are now using humidity levels in order to predict seasonal influenza outbreaks across the world12

Toxin Exposure

There is considerable evidence showing a relationship exists between toxin exposure such as persistent organic pollutants (POPs) and the frequency of common cold and influenza “infections”. For example, prenatal exposure to POPs is associated with higher levels of POPs present in umbilical cord blood and the number of reported airway infections during the first 10 years of age13,14. This is supported by evidence from other studies showing a significantly increased risk of respiratory infections and POP exposure during childhood15 and adolescence16. Exposure to air pollution (POPs, ozone, particulate matter etc) is also associated with a greater rate of hospital admissions for respiratory infections like influenza in the general population17,18.

There are many factors well established in the scientific literature, that are known to induce influenza-like-illness, but are not viral in nature. The fact that toxin exposure, detoxification and withdrawal from drugs causes influenza-like-illness lends further plausibility to the hypothesis that influenza might be a detoxification response. A number of these non-viral causes of influenza-like-illness present with symptoms that are indistinguishable from so called “vial influenza”. Given that environmental exposure to various toxins can cause a disease so similar to influenza, that it is often misdiagnosed as such19–21, is it that big of a stretch to think that just maybe, influenza is the body’s response (ie antidote) to toxicity?

Below is a list of common environmental toxins and drugs which cause influenza-like-illness;

Toxins That Induce Influenza-Like-Illness

Organophosphate toxicity22

Pesticide exposure23

Air pollution24

Endotoxin & cytokine exposure25

Persistent organic pollutants (POPs)26

Metal fume fever27

Polymer fume fever28

Dippers flu29

Carbon monoxide toxicity19

Smoking cessation30

Electromagnetic radiation31

Drugs That Induce Influenza-Like-Illness

Caffeine withdrawal32

Opiate withdrawal33

Anti-depressant medication overdose34 & withdrawal35

Anticonvulsant medication withdrawal36

Oral contraceptives37


A Detoxification Process?

Could influenza be a detoxification process initiated by the human body to cleanse itself of accumulated toxins, rather than being caused by an external pathogen? There has been recent discussion within the medical and broader health community as to whether or not influenza might be like a “spring clean” for the body. When a certain level of toxins accumulate in the bodily tissues, could an internal response be generated by the body? Could this detoxification process be triggered in order to purge toxins from an over-burdened system? At first this might seem like a far-flung theory, however upon closer inspection, the scientific literature reveals that flu like symptoms do occur in individuals after acute and chronic exposure to toxins39.

Let’s assume for one moment, that this theory of detoxification is plausible, what could trigger such an event? You may be surprised to learn there is a relationship between humidity and the levels of toxins in the atmosphere. It is well established that environmental toxins (both natural and man-made) are found in significantly higher concentrations in the atmosphere during the humid, Summer months40,41. As the humidity drops, so do the levels of atmospheric toxins and the subsequent human exposure to these toxins40.

It has already been established earlier in this blog post, that influenza outbreaks are triggered when the humidity drops to a specific level. The currently accepted reason behind this is that the low humidity dries out the mucous membranes of the nasopharynx and the lungs, leaving them more vulnerable to viral infection8. Is it possible, that the reduction in humidity, might instead signal the body to enter in to a period of convalescence and detoxification, in order to cleanse the body from the toxins accrued during the Summertime?

If we think about this logically, doesn’t it make perfect sense for the body to detoxify when the levels of environmental and atmospheric toxicity are at their lowest? Doesn't it also make sense for the body to start getting rid of mucous containing toxins during periods of low humidity (ie cool dry Winter air)? Have you ever tried drying your wet clothes outside on a very humid day, it doesn't work so well does it? This hypothesis might also explain why some people are seemingly immune to influenza. If they were exposed to low levels of toxins during the Summer, there may not be a sufficient toxic load for the body to initiate a detoxification process that Winter. It's also evident that not everyone gets sick in Winter, so could it be that individuals with a very high toxic burden, experience several detoxification events throughout the year due to sheer necessity, despite changes in humidity?

Toxins are known to accumulate in the body, not only from environmental exposure, but also from exposure to toxins contained within the food and water supply, drugs, personal care products (sunscreen, makeup, soaps etc) and cleaning products for example42,43. It is also well known that individuals who smoke cigarettes44 and abuse alcohol45, are at greater risk of influenza. Therefore, is it possible that people who have very low exposure to these toxins might undergo less frequent detoxification processes, which could explain why some people only get a flu once every 5-10 years?

There is evidence to suggest that toxins and POPs are excreted in bodily fluids such as breast milk and saliva46. Whilst we do know that the mucous within the respiratory tract traps and eliminates inhaled toxins47, to date there seems to be no studies investigating whether or not there is an increased concentration of toxins being excreted in the respiratory mucous during influenza and the common cold. Such evidence would be very useful in helping to determine whether these illnesses may indeed act as a detoxification process.

Final Thoughts

There has never been a more important time in human history for people to ask serious questions about what is really making humanity sick. We simply accept that influenza is caused by a virus because we have been conditioned to believe it is so. It’s unfathomable to most people that there could be any other rational explanation, so naturally, there is a resistance when this topic is brought up. Instead of questioning our reality, we simply take the words of men in white coats or those in positions of power, as gospel. Is it possible influenza is caused by a virus? Yes, of course. Is there any solid scientific evidence to prove that it is the cause? It’s possible that this evidence does exist, however in over 2 years of searching, neither myself, nor hundreds of other medical professionals and scientists who have looked in to this topic, have come across such evidence.

Now is the time for humanity, science and medicine to start thinking outside of the box when it comes to germ theory. We need to be able to have open and honest intellectual discussions about this topic to try and find out what really makes us sick. If we continue to believe that a germ is the cause when it (possibly) isn’t, we will always be barking up the wrong tree, resulting in continued declining health, ineffective treatments and prevention strategies, and continued intrusion upon basic human rights and freedoms, all in the name of "stopping the spread". Until the true underlying cause is identified and dealt with, it will continue bubbling away, insidiously destroying humanity, hidden behind the veil of an outdated and obsolete theory of the “germ”.

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