When it comes to protecting yourself from a contagious virus, there’s nothing more important than the nose because your nose is COVID-19’s royal road into the rest of your body. Your nose is also your body’s first line of defense against viruses and other pathogens. Let’s get better acquainted with your nose. The photo of the handsome proboscis monkey is from an Image by Volker Lekies from Pixabay
Some noses are long and thin. Other noses are flat and broad. Still others lie somewhere in between. Let’s face it, some noses are small and dainty and some are huge. One of the best known noses belonged to the late Jimmy Durante. His nickname was Schnozzola. This term is an adaptation of the Yiddish word schnoz or nose.
Jimmy could have cracked this joke in 2020.
Was I mortified when I hoid youse was sick! I’ve got a noseful of geims – but it makes DEM sick! JimmyFrom the Library of Congress
If you’ve never heard of Jimmy Durante, watch this video of his performance with the Harry James band.
The Nose as Border Patrol
Dr. Angela Pizzola and Dr. Linda Walkim, researchers at the University of Melbourne, are trying to develop anti-flu vaccines that target the immune responses of the nose (Pizzola et al., 2017). Since, the nose is where the body first encounters flu viruses – a kind of nasal border patrol – the researchers asked why not look for immune cells in the nose. https://pursuit.unimelb.edu.au/articles/stopping-the-flu-virus-at-the-nose
How Today’s Flu Vaccines Work
Today’s flu vaccines don’t target the nose. Our annual flu shot is virologists’ best prediction of the virus strains which can be expected in the following year. Based on these scientific guesses, laboratories then develop a vaccine against these strains, manufacturers start producing the vaccines, and the vaccine is rolled out in pharmacies and clinics. The vaccine, made from inactivated viruses, stimulates white blood cells in the host’s body which will fight these specific invaders when the external features of the targeted viruses are recognized.
Problems with the Current Flu Vaccines
There are several limitations to this vaccine approach:
- The scientists could guess wrong and select viruses that never appear or cause problems.
- A target virus could change its external structure by the time the vaccine is rolled out, so the white cells won’t recognize the virus or attack it.
- Since viruses are constantly changing their external structures, we face the impossible task of developing a new vaccine for each variation the virus might adopt.
- We must roll the dice and take a flu shot each year.
One-Shot Vaccination Targeting the Nose
Researchers started their search for a one-shot flu protection by looking at a particular type of cell — the resident memory CD8 T cell or Trms. Trm cells in the lungs provide excellent protection against the flu. Trms differ from other cells because they reside in body structures such as the lungs or heart as opposed to the blood stream. They can also live for a very long time.
Difference Between One-shot and Current Flu Vaccinations
The most important difference between vaccines using Trms and the current vaccines is their target. While current vaccines target the external constantly changing features of a virus, Trms based vaccines target the unchanging internal parts of the virus.
What Vaccines Based on Trms Might Be Able to Do
The flu-fighting cells in the nose might disable the inhaled influenza virus in the nose and upper airways and prevent an infection from reaching the vulnerable lungs. A vaccine targeting nasal Trms could be administered just once and provide protection against any viruses you might encounter in your entire life –- including pandemic strains.
This means a vaccine that induces flu fighting Trm cells in the nose could outwit the flu virus.
Why Write about a Treatment Option that Exists only in Scientists’ Imaginations?
We should understand where we’re going to evaluate where we are. Vaccines aren’t a cure all. They aren’t a shield against every bad virus coming our way. We need to look carefully at the new vaccines before deciding which vaccine to take. The vaccines are not equivalent and work in different ways with differing side effects. More on this in a later post.
How the Nose Protects Us from Viral Infections
The nose is a complex organ with a variety of functions. One of these functions is immobilizing pathogens before they pass into the lungs. The characters in the battle between the body and pathogens are identified in the figure below. When pathogens or foreign particles (blue) enter the nostrils, they are trapped in a river of mucus. This mucus layer moves toward the pharynx or our throats.
The Epithelial Lining of the Nose
The epithelial lining of the nose has four major parts. The top is layer is a river of mucous (light blue). Note that the mucous layer traps viruses (teal) and bacteria (lavender). Below the mucous is a layer of epithelial cells. The goblet cells secrete the mucous needed to trap pathogens. Specialized cells with vibrating cilia serve to move the mucous along. Below the epithelial layer, the blood vessels and the immune apparatus attack and immobilize pathogens.
Health of the Mucous Flow and Cilia Movement
Watch these brief tutorials. The first shows the mechanics of the cilia within the respiratory system. The second shows how vulnerable the movements of the cilia are to changes in humidity.
Do You Live in a Low Humidity Environment?
If you live in an area with low humidity or when the humidity in the air you breathe is decreased by your furnace, give serious consideration to using a humidifier to bring your room air to 45%. The ability of the immune cells in your nose to attack pathogens is decreased in low humidity. Not a good thing.
Is Nasal Anatomy Relevant To COVID-19?
Yes, this information is particularly relevant to COVID-19 because the COVID-19 virus can be stopped in the nose before it makes significant inroads into the lungs and the rest of the body (Hua, 2020; Sungnak et al., 2020). These researchers analyzed the RNA sequencing from datasets of the Human Cell Atlas Consortium. The researchers asked whether cells in the lung, nasal cavity, eye, gut, heart, kidney and liver had the key entry proteins needed by the COVID-19 virus to infect human cells.
COVID-19 Needs the ACE2 Enzyme to Penetrate Our Cells
COVID-19 can only attack our bodies when the right conditions are present. For COVID-19 to enter our cells, the cells must have the ACE2 enzyme.
ACE2 is present in the ciliated cells of the nasal epithelium, and there is more ACE2 in the nose than anywhere in the respiratory system. Our lungs have fewer ACE2 expressing cells, so the nose has what COVID-19 needs to multiply.
Our Noses Are Easily Infected by Viruses
The nose passes another test for primary infection site. The nose is readily infected by virus laden aerosols. When subjects breathe normally, aerosols containing viruses are inhaled into the respiratory system. The highest deposition density of these aerosols is in the nose. Large aerosols are more likely to end up in the nose and smaller aerosols are more likely to find their way into the lungs (Sungnak et al., 2020).
Proof that the Nose Is the Primary Infection Site for COVID-19
Using autopsy data from patients who had been diagnosed with COVID-19, researchers established that the pattern of infection in the lungs is consistent with an infection starting in the nose, creating large balls of mucus, and then infecting the lungs. If the COVID-19 infection were caused by small aerosols finding their way into the lung, we would expect a homogeneous scatter of infections throughout the lungs. If the infection were caused by infectious balls of mucous discharged by the nose, a scattered disease pattern is more likely. The infection pattern in patients with COVID-19 is patchy.
It Probably Works Like This
We breathe in virus-laden aerosols or expose our noses to viruses from hand to face contact, and the viruses are caught up in the river of mucous secretions. The nasal secretions are swept from the nasal surface and into our mouths. In the mouth, the viruses accumulate and multiply. Sometimes, a bolus (ball) of virus-containing mucous is formed. This infected ball moves from the mouth into the trachea. In the trachea, the viruses accumulate in the lining. Again, a bolus of mucous infected with virus is formed.
Viruses May Move Into Our Lungs at Night
At night, balls filled with viruses are drawn deeper into the respiratory system when we breathe or by gastro-esophageal reflexes. Once in the lungs, these boluses have a sufficient viral load or number of viruses to initiate the lung infection.
Don’t Neglect Your Nose
If the nose is the initial infection site (COVID-19’s ground zero) and if the infection is secondarily seeded to the lungs by aspiration, there are three major implications for our health practices.
- Wear a face mask to prevent large, very infectious virus laden particles in the air from entering the nose.
- Stop touching areas around your nose, eyes, and mouth where a virus can enter.
- Decrease the virus titer or number of viruses in the nose, so COVID-19 cannot gain a foothold.
How Do I Keep COVID-19 from Making Me Sick?
Of the two interventions we can do, stopping our busy little fingers from touching our faces is the harder. It is an unconscious habit, and the topic requires a separate post. Stop Touching Your Face! The second intervention may surprise you. You need to wash the interior of your nose with a hypertonic saline (salt diluted in water) solution.
How Do I Wash My Nose?
Nose washing with a saline solution is called nasal lavage. Hindus have practiced nose cleansing for thousands of years, and the earliest record of nasal irrigation is found in the Hindu practice of Ayurveda.
There are two cleansing techniques — Jal Neti and Sutra Neti. Jal Neti is the procedure used in medical applications. Jal Neti uses a neti pot filled with lukewarm saline water. Nasal washing with a neti pot can remove dust, allergens, and drain the sinuses. The procedure can reduce the inflammatory mediators in the nasal secretions of sinusitis (Gupta and Gupta, 2020).
How Is a Neti Pot Used?
The image below shows a traditional neti pot on the left and the correct position of the head. The neti pot has an angulated spout and holds enough water to cleanse both nostrils. The spout of the pot is brought close to the nostril to make a perfect seal. A downward and sideward inclination of the head facilitates the easy passage of salt water through the nasal passages via gravity. The saline enters one nostril and exits through the other as the user breathes through the mouth.
Nasal Lavage and Allergies
Many allergy and sinusitis sufferers get relief from their symptoms by flushing their nose and sinuses with saline. Allergies are caused by pathogens such as pollen. These pathogens are trapped in the mucous of the nose in the same manner as a virus or a bacterium. These foreign bodies induce some of the same immune defense mechanisms as a virus. Nasal lavage has become an accepted treatment for sinusitis and allergies (Casale et al., 2018).
Nasal Irrigation and the Common Cold
Scientists use the term nasal irrigation rather than nasal lavage. If nasal irrigation helps allergy sufferers, could it also alleviate the symptoms of viral pathogens such as the common cold or annual flu? The initial results of my literature search weren’t overwhelming, but they were promising.
Definition: Saline is delivered to the nose in a large-volume wash using reservoir pots and tubing or in a small volume via spray devices that deliver a fine spray or jet of saline into the nose.Kassel et al. 2010
Possible Benefits of Nasal Irrigation
There were two recent meta-analyses (Kassel, King, & Spurling, 2010; King, Mitchell, Williams, & Spurling, 2015). The reviewers defined nasal irrigation.
- Saline irrigation of the nose may have some benefit in patients with acute respiratory infections.
- There are no dangerous side effects linked to the correct application of the saline solution.
- Saline irrigation might make the mucous stream move better by increasing ciliary beat frequency and clearing infectious materials from the sinuses. A good thing.
Oops! Here Comes the World Health Organization
Like everything associated with COVID-19, it seems that authorities aren’t shy about putting forth opinions without any consideration of available research. The case in point is the World Health Organization, which has a very low accuracy batting average in my book. Read the WHO’s guidance on nasal lavage.
Please Make Up Your Mind!
If you read the large print from the WHO, washing your nasal cavities with saline solution is a myth. If you read the fine print, the WHO tells us that washing the nose with saline can help you recover more quickly from the common cold. The organization won’t recommend nasal lavage, but they won’t rule it out either. The WHO has done a phenomenal job of fence sitting.
How Much Salt Must Be in the Salt Solution?
Recent research proves that it is the amount of salt in the lavage solution which counts. What is needed to reduce the reproduction of a virus in our nose is a hypertonic solution. Hypertonic saline washes deliver a stronger concentration of salt to the nasal cavity and sinuses than do an isotonic solutions.
The studies upon which the WHO based its opinion had used isotonic solutions, at the same pH as the bloodstream. You need more salt to slow down a viral infection.
Elvis Has a Message for the WHO.
Return to sender. Address unknown.
Image from dreamstime.com/Free_Images/ Stock
The ELVIS Study Shows Hypertonic Nasal Irrigation Can Help
Sorry to mislead. Elvis didn’t conduct this study. In this case, ELVIS stands for the Edinburgh and Lothians Viral Intervention Study (ELVIS) (Ramalingam et al., 2018; Ramalingam, Graham, Dove, Morrice, & Sheikh, 2019, 2020). Hypertonic nasal irrigation combined with gargling can help you deal with a coronavirus.
ELVIS Study Results in Brief
Washing the nasal cavity with a strong saline solution does the following:
- Upper respiratory tract infections last 5 days as opposed to 8 days on the average.
- Cough, stuffy nose, and hoarse voice last 3 less days.
- Discomfort requiring over the counter medication is reduced by 36%.
- Adding baby shampoo to the wash may increase its effectiveness against coronaviruses such as COVID-19. https://news.vumc.org/2020/08/27/trial-to-test-nasal-irrigation-to-treat-covid/.
- You are less likely to spread a coronavirus if you wash your sinuses with a saline wash.
How Does a Hypertonic Saline Solution Slow Down COVID-19?
I think the answer may surprise you. The epithelial cells lining the nose and respiratory system fight viruses and microbes by producing hypochlorous acid (HOCl), a weak unstable acid, from chloride ions (Ramalingam et al., 2018).
As a reminder, saline solution is made up of salt and water. Salt is composed of only two elements, sodium and you guessed it, the friendly chloride ion.
Chloride and Immunity
Chloride, the most abundant anion in humans, is an important prerequisite for the innate immune response mediated by immunity cells (phagocytes and neutrophils). The ways in which hypochlorous acid acts on several pathogens that make us sick — viruses, bacteria, allergens, and odors — is shown in the figure below.
How Does This Apply to COVID-19?
You may be thinking that the studies on coronaviruses have nothing to do with this novel coronavirus, COVID-19. Stop thinking that. Studies on the impact of salt solutions on COVID-19 are just being published.
Now we know that COVID-19 viruses are found in great numbers in the nose and throats of individuals who carry COVID-19 and don’t have symptoms as well as those who are sickened. It’s the presence of these viruses in the noses of asymptomatic carriers of COVID-19 which is fueling the rapid spread of COVID-19.
You don’t have to feel sick to spread COVID-19.
How Do You Measure the Impact of Salt on COVID-19?
There are two ways to measure how salt affects COVID-19 survival. The first is a clinical study using real people of the type done by Ramalingan and colleagues, and the second is an in vitro study using isolated cells.
What Happens to the COVID-19 Virus When It’s Exposed to Salt?
Ramalingam and colleagues tested a wide range of enveloped and non-enveloped viruses ranging from herpes simplex to enveloped coronaviruses similar to COVID-19. All human viruses tested were inhibited in the presence of sodium chloride.
Does The Amount of Salt in the Wash Matter?
The answer is “Yes.” Up to a certain point, the amount of salt in a solution does affect the survival of COVID-19. A study of the impact of NaCl or salt on COVID-19 was published by Machado et al. (2020). Primate lung tissue was used to do the analyses.
Interpreting the Study Results
The horizontal axis is the concentration of salt used (amount of salt in solution increases from left to right). The vertical axis is the number of viruses. Four conditions are shown in the graph. Gold = virus preincubation; Red = absorption plus post-infection; Green = absorption; and Purple = post-infection. Green and yellow lines show what the virus looks like before or early in salt treatment. Red and purple lines show what the virus looks like after being exposed to salt. Note the following:
- Exposure to an increasing amount of salt in a solution disrupts COVID-19 more and more.
- The impact of salt on the COVID-19 virus reaches its peak at 1.4 to 1.5%.
- NaCl decreases viral replication by more than 90%. Wow!
Hypertonic Saline Solutions as a Viral Birth Control
Is a saline solution birth control against viruses?
Ramalingam et al. believed that the inhibition of the viruses was not caused by toxicity outside the host cell, but they argued that something specific was happening inside the virus which slowed reproduction.
How COVID-19 Is Inhibited by Salt
The COVID-19 virus cannot survive in salt solutions of at least 1.5%. In these solutions, virus reproduction slows to a near halt (Machado et al., 2020). Machado et al. suggested that salt interferes with conduction across the cell membrane. This research gets a little dense. To get a better grasp, check out the article.
Washing the Nose with a Salt Solution Plus Gargling is Better
You improve the virus fighting properties of nasal salt washes when you also gargle with salt. When researchers looked at the number of viruses being shed, gargling and nasal washing together reduced this significantly (Ramalingam et al., 2020).
Will Other Types of Gargling Help?
Even gargling with plain water may help prevent upper respiratory infections (Satomura et al., 2005). Perhaps, the mechanical action of gargling with the whirling forces dislodges viruses.
Nasal Irrigation Is Key to Reducing COVID-19 Progression
In a new study, patients will use nasal solutions with different acidity or alkalinity. They will do the treatment twice a day for two weeks. The investigators see nasal lavage as a way to help high risk patients who can’t use vaccines reduce their likelihood of getting sick.
A Simple Way to Reduce Viral Spread
Listen up, people. You can protect others from getting your gamboo. Washing your nasal cavities with saline with slow the spread of a coronavirus to those you know, love, or happen to be around by 35%.
Change Your Way of Thinking
Staying away from others when you feel the early symptoms of a flu or cold is pre-COVID-19 advice. Welcome to an unpleasant and new reality of COVID-19. You can make other people sick before you feel any symptoms. Damn! Where does that leave us? What a horrible reality. I wish I had an easy answer, but I don’t.
My Best Advice
The best advice I can give is to use nasal lavage and gargling with saline solutions to protect the ones you love even if you have no symptoms. To read more about how the act of breathing spreads COVID-19, see this post. The link will be added when the post is completed.
I rinse my nose with saline after I return home from a trip to the grocery or anywhere else. I also use nasal lavage before bedtime to discourage any viral laden boluses from moving into my lungs.
During a pandemic, during a bout of flu, or during a common cold, washing the sinuses with a saline solution can reduce the ability of a virus to reproduce. This means that we can reduce the number of viruses in our upper respiratory tract. This translates into a reduced duration and severity of illness. This also translates into less spread of the virus to others.
Washing the nasal cavities with a saline solution will not prevent COVID-19. You can still get COVID-19, but you may slow the infection and protect others.
Thinking About Trying Nasal Irrigation?
There’s a lot to know. To get the specifics on nasal irrigation equipment, nasal wash fluids, safety, go to the related post. The post is being written and should be ready soon. Check back.
Want to Know More?
This post was updated from a chapter in our book. It’s available in digital form from several distributors. Click the link.
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