What is a virus?
Viruses are microscopic parasites, significantly smaller than bacteria, approximately 5-300nm in size (a nanometer is a millionth of a meter)1. These tiny particles consist of RNA or DNA genetic code, surrounded by protein.
While some scientists debate whether viruses are actually alive or not, the fact is that viruses cannot live on their own, as they require a host to divide, replicate, and grow. A host can be an animal, plant, bacterium, or fungus.
An apt analogy is a computer virus, which, just like a biological virus, is really just a code. When this code encounters a host (i.e. a computer or biological organism), the code sends a message to that cell, allowing the virus to run its code in the host and replicate.
Not all viruses are compatible with all hosts. Using the computer analogy, a virus for Microsoft computers will not work on Apple computers. Likewise, there are thousands of bat viruses that cannot harm humans. On the flip side, some viruses are compatible with more than one host (i.e. animal and human), and this is where we can see a virus replicating in both animals and humans.
If a virus is “sort of alive,” then how exactly does it function?
A virus must first find its way into the cells of a host. It is not always easy to penetrate a host cell’s outer membrane. But once a virus breaks in, its viral genome (an instruction kit of sorts) communicates to the host cells to make more viruses. When an individual host cell dies, it spreads the virus to additional cells. If this process reaches a critical stage of replication, the host becomes ill.2 This is what we mean when we’re sick “with a viral infection” such as influenza (i.e. the flu).
Viruses are also continually changing during replication, undergoing subtle genetic changes through mutation.3 This often results in the virus becoming stronger and more adaptable to the host. The virus’ ultimate goal is to create greater opportunities to replicate and grow. Mutations assist in this strategy. A prime example is why the annual flu shot may not always be effective, as the particular strain (or mutation) has changed, and the shot (developed from a prior strain) becomes no longer useful.
Viruses are spread by bodily fluids, such as through coughing or sneezing, which transfers those fluids to surfaces (i.e. door knobs, desks, etc.) where others then have direct contact. Alternatively, viruses can become aerosolized (or “airborne”) when sneezing and coughing into the air, which others then breathe in. Viruses can enter your body in many ways through these processes. For example: a virus may land on your skin through after settling out of the air. The virus on the back of your hand does not pose a health risk directly, unless the skin is open, such as a cut or wound. The virus could enter at that point only. But it you put the back of your hand to your mouth, then the virus could be transferred to you via your saliva. This is why it is critical to wash your hands after any type of exposure outside of your home.
A virus can come from another species.
Wild animals, whose habitats are under pressure from human agricultural and urban development, have become stressed. Under the same conditions, you too would be stressed. Think about how you feel when things are difficult at work or at home. Our body’s defenses are lowered when we are under constant pressure and stress. This leads to a greater chance of becoming ill from a pathogen if exposed, as our immune systems do not have the resiliency needed to remain healthy.
Given the extensive land development into formerly wild environments, the human and animal communities are now closely entwined in ways we historically have not been. We interact and overlap using the same spaces, which increases the potential for a virus to transfer from animal to human, through something as simple as a scratch, a bite, or a sneeze. And if the human is found to be a compatible host, then that virus can replicate, thereby jumping from animal to human.
What is COVID-19?
On March 11, 2020, the World Health Organization declared that COVID-19, an infectious disease caused by the newly identified coronavirus, SARS-CoV-2, could be characterized as a pandemic.4 Coronaviruses are a type of virus. There are many different kinds, and some cause disease in humans. COVID-19 first emerged in Wuhan, China in December 2019, and quickly spread throughout the world. While health officials are still investigating the origin of this virus, it is hypothesized that it may be linked to a seafood market in Wuhan.
Much also remains unknown about the disease’s spread, although research data shows that the new coronavirus is spread through droplets released into the air when an infected person (whether symptomatic or asymptomatic) coughs or sneezes. These droplets travel only a few feet in the air, and then fall to the ground in a few seconds.5 This is the rationale behind the public health directive to physically distance a minimum of 6-feet, and to wear face masks in public, to effectively prevent the spread of disease. Other methods of transmission (i.e. surface contact, aerosol droplets, etc.) are presently being studied and analyzed.
The Centers for Disease Control and Prevention (CDC) have tracked a wide variety of symptoms related to COVID-19, including fever or chills, cough, shortness of breath, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, and diarrhea.6 While anyone can contract the virus, older adults and those with severe, underlying medical conditions (i.e. heart or lung disease) appear to be more at risk for developing serious complications from COVID-19. Individuals in those higher-risk populations should take additional precautions to protect themselves from contracting the virus.
It’s worth noting that COVID-19 is not the flu. Influenza (flu) is caused by an infection with influenza viruses. COVID-19 is caused by an infection with the new coronavirus SARS-CoV-2. And while both infections can manifest with similar symptoms, there are also fundamental differences between the two. COVID-19 appears to spread more easily than the flu and causes more serious illnesses in some people. People with COVID-19 can be contagious for longer than the flu, and also be asymptomatic for longer periods of time.
The best way to confirm whether or not you have the flu versus COVID-19 is to take a viral test to see if you have the infection. If you test positive for COVID-19, you will need to follow protective steps to prevent others from getting sick. If you test negative for COVID-19, the test result only means that you did not have COVID-19 at the time of testing. And you should continue to take steps to protect yourself. You can find out more about getting tested in your local community on the CDC website.
Why do we not yet have a vaccine for COVID-19?
The human body can typically handle viruses on its own without falling ill. However, some viruses overrun the body’s immune system, and medicine may be needed to eradicate the virus. For example, in some cases, antiviral drugs work by either blocking the entry of the virus into the cells, or by preventing it from replicating.
The challenge is that different viruses have different sets of codes and delivery mechanisms. To return to our computer analogy, some viruses enter the system by downloading a file from your mail program; others use your web browser to gain access. Once downloaded to your computer, some viruses require you to open the document to release the code; while others run automatically. Their actions are different as well, with some watching keystrokes for passwords, some others lock you out of the system, and some delete files.
Researchers may try stop a biological virus by “not downloading it,” meaning not letting it attach to a cell in the first place; or by “not opening the file,” meaning not letting the code enter the cell. But this takes a tremendous amount of research and trials to determine. And even so, computer viruses pale in comparison to the possibilities presented by biological viruses. This variability makes it difficult for researchers to find the right set of actions and methodologies to stop a particular virus, particularly one that has not yet been seen or tested before in the human population.
The world’s best researchers are currently working on solutions using the most sophisticated tools and knowledge to find a vaccine for COVID-19 as quickly as possible. These researchers are analyzing how the virus works to create frameworks for antiviral medications and vaccines.
Clinical development of a vaccine occurs in three (sometimes four) official phases. During Phase 1, small groups of people receive the trial vaccine. In Phase 2, the vaccine is given to people who share characteristics similar to those for whom the new vaccine is being developed. In Phase 3, the vaccine is rolled out to thousands of people and tested for efficacy and safety.7
Vaccines require human clinical trials before deployment to the mass populations to ensure there are no severe nor unusual reactions to the drug. There are obvious and inherent risks to participating in vaccine clinical trials, particularly if the participants are infected with a live virus. Side effects and adverse reactions are closely monitored and tracked. But there is, of course, no guarantee of absolute safety from any vaccine participation trial nor vaccine.
The Vaccine Adverse Event Reporting System (VAERS) was established in 1990 to detect possible safety problems in U.S.-licensed vaccines. Co-managed by the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA), VAERS accepts and analyzes reports of adverse events after a person has received a vaccination.8 In the United States, the FDA will only license a vaccine if the benefits outweigh the risks.
Once approved, millions of vaccines need to be manufactured and distributed to the population. There are some logistical challenges with these steps. Many vaccines are delivered by needles, and some are temperature sensitive. Delivering them around the world requires all vaccines to be kept at proper temperature as they’re transported from the factory, on the plane, on the truck, into the doctor’s office, and finally to you. Corporations, federal agencies, and individuals around the world are working on this process for the upcoming COVID-19 vaccine, with the hopeful promise of delivering a safe and effective vaccine as soon as possible.
Vaccines do not treat or cure the disease; they prevent them from happening. A vaccine contains the same virus that causes the disease, but either a dead version of that virus, or a significantly weakened form. Some vaccines only contain a part of the virus. The vaccine works by stimulating your immune system to produce antibodies to the virus, similar to if you had actually been exposed to the pathogen and became ill. After getting vaccinated, you develop immunity to that disease, without ever being sick from it.9
How can I keep viruses out of my body?
How can we stay healthy? The most effective means to avoid contracting viruses is to stay as healthy as possible at all times, particularly during flu season, and to boost your immune system. Balanced nutrition, exercise, rest, and mental wellness are all critical to ensuring our immune systems operate at peak performance. This pandemic is indeed a stressful time for everyone, with job losses, schools closed, remote work, lack of in-person connections to friends and family, and more. Historically, the world has faced other pandemics and viral epidemics. We will emerge from this one as well. Commit to staying as physically and mentally strong as possible, and if possible, help your family and friends do the same.
Most people don’t realize that our bodies are covered with billions of tiny micro-organisms of bacteria, protozoans, fungi, and viruses, on a daily basis. We refer to this as our “microbiome,” and it is what keeps us healthy and thriving humans. These amazing micro-organisms are our first line of defense from other micro-biological invaders. We know that eating yoghurt helps our stomach digestion, because it provides the good bacteria that the gut microbiome needs for proper functioning. However, that example is just one of millions. There is still much research needed to explore the rest of the microbiome, what it means, how it works, and what we need to do to maintain optimal health.
When our microbiome is healthy, we are healthy. When our microbiome is sick, we are sick. There is much that connects our individual microbiome with disease and immunity. Why does one person get sick from an external pathogen, and another person does not? How does our body handle the presence of a foreign virus? Why do some people carry a virus, and yet not appear symptomatic (i.e. in the case of influenza, studies have shown that up to 50% of people who have the flu do not actually show any symptoms of it10).
The microbes that compromise our microbiome contribute to our body’s metabolic functions, protect against pathogens, educate the immune system, and impact our physiology.11 The Human Microbiome Project12 is a tremendous project tasked with researching how a person’s microbiome may influence their susceptibility to infectious diseases.
So how do I interact in the world and not get infected?
Some viruses can stay viable outside of the body for hours, while others cannot. To control the spread of viruses, stay home if you are sick or if you think you have been exposed to a virus. It is possible to be a carrier of the virus even if you do not exhibit symptoms. This is why it is critical to wear a mask at all times in public, so that you keep both yourself, and others around you, healthy and safe. Wearing a mask reduces your ability to contract a virus.
The second most important detail is that your mouth and nose are the absolute weakest points on our bodies, and the protection of these when out in the neighborhood is vital. This is accomplished by wearing a face mask. If a virus cannot reach your mucous membranes, it cannot take hold.
We have hard evidence that surgical/medical masks work effectively, because healthcare providers have consistently worn these for years to prevent the spread of illness. At the moment, however, surgical/medical masks are in limited supply, and high demand. They really should be retained for our frontline workers.
When you are out in public, consider wearing re-usable/washable cloth masks. These are more cost-effective and better for the environment. Waste managers are already seeing an increase in disposable masks in waste streams. Cloth masks are both effective and can be individualized to your personal style. And there are already dozens of patterns, colors, and variations on the market to suit every face type and size. Face masks must cover both your nose and your mouth to be effective. The World Health Organization (WHO) has provided some great videos on how to wear a cloth face mask safely:
But, it’s hard to breathe when wearing a face mask…
Yes, it’s unfortunately true that it’s harder to breathe when wearing a face mask. As Bill Nye demonstrated, try blowing a candle out while wearing one. It is pretty hard to do. But that’s precisely the point. What Nye’s candle experiment shows is that it’s very difficult to spread droplets of water from you to others while wearing a mask. But that simply means it is working to protect you and others and helping to stop the spread of COVID-19.
Many people are also concerned that wearing face masks leads us to breathe in our own carbon dioxide, while fostering a lack of oxygen. The WHO has also addressed this myth. If this were true, medical professionals around the world would have passed out during routine surgeries over the last decades, if not centuries. It is harder to breathe when wearing a mask, yes; but it is not an individual health risk. It is, however a very serious and real health risk to be out in public spaces and inside public buildings without a mask on.
Do I need to wear gloves to protect myself?
The WHO says that wearing gloves is not as effective as regularly washing your hands. Some stores may give you gloves to wear when you enter, because those retailers may want to double down on their own protection methods. But while doing your shopping in public, simply put some hand sanitizer on your hands before you enter the store, make sure the cart handles are sanitized, and then sanitize your hands once again upon leaving the store.
Should I be washing my groceries when I bring them into my home?
The WHO states that there are no confirmed cases of the virus transmitted through food or food packaging. You do not need to wipe down your groceries when you get them home. If, however, you are already accustomed to washing your produce, make sure to use a food safe detergent and then rinse thoroughly with water.
More importantly, when you return home from any public places, you should wash your hands thoroughly. Think of this as a decontamination process every time you come back into the house.
What do I need to know about washing my hands and hand sanitizers?
Soap and water are always the best, most effective, options, and should be your default around the house and wherever possible. Washing your hands with a mild, scent-free soap won’t dry out your skin. The more chemicals and scents in your soaps, the more your skin will become dry. Consider natural soaps like glycerin and castile. You should wash your hands for at least 20 seconds. Remember this by singing the Happy Birthday song twice, God Save the Queen, or a variety of other more fun and musical songs.
When hand washing is not possible, hand sanitizers are the next best option. Hand sanitizers must contain at least 60% alcohol to be effective. Also, make sure that it does not contain methanol, a toxic alcohol that can have adverse effects. If you want to make your own hand sanitizer, the WHO has recipe on their website for larger amounts; but for you and your family, you can use this scaled-down recipe.
What’s the bottom line when we go outside of the home?
Minimize the number of trips you take outside of the home. If you are not going out, you are less likely to be exposed. It is as simple as that. When you do go out, wear a mask, and wash or sanitize your hands as much as you can. Do not touch your face while you are out, especially your mouth and nose, unless your hands are 100% clean. Once home, wash your hands again.
Is there anything I can do inside my home to make it healthier and safer for my family?
Most importantly, make sure everyone in your household washes their hands frequently, particularly before eating, and after using the bathroom, blowing their nose, coughing or sneezing, changing a diaper, and touching animals if they have been outside.
Of additional importance is cleaning all regularly touched surfaces, such as door handles, the fridge handle, counters, water taps, toys, and electronic remotes. Germs, including viruses, can be transferred from many of these surfaces. Make sure you use non-toxic cleaners, as toxic cleaning products will add an additional burden to an already stressed-out body. Particularly since many of us are now working and learning from home, it’s important to keep up with a regular cleaning regimen.
Cleaning seems easy enough. What else can we do?
Proper ventilation can reduce the aerosolization of viruses that have been expelled by indoor occupants. The less ventilation in a space, the longer the virus can linger in the air, and the greater potential for occupants to inhale the virus. Think about how the room of a sick person feels stuffy from the germs that float around and remain in the air. When a healthy person enters such a room, they can breathe in these pathogens and become ill. More air in a room and better air exchange will flush out germs more efficiently.
It is recommended to open all of the windows in your home once or twice a day for a few minutes. However, this is dependent on climate and outdoor pollution levels, as you could have very hot, humid air, or polluted air coming into your home, thereby aggravating asthma or allergies. When opening windows is not possible, then mechanical ventilation can be used. Install a fan in a window to exhaust outside, so instead of blowing air in, it pulls air from other parts of the building, effectively circulating and moving air. If you have bathroom fans, or kitchen exhaust fans that exhaust outside, running those can also be helpful.
The best solution for mechanical ventilation is to have balanced air exchange where air comes in the home and is conditioned (dehumidified, heated, or cooled) and stale air is exhausted. You may already have this in a heat recovery or energy recovery ventilator.
Humans prefer the relative humidity (RH) in the air, meaning the amount of moisture in the air, to be around 35-55%. Not too damp and not too dry, but somewhere in the middle of the two extremes. Typically dust mites, mold, bacteria, and viruses prefer different conditions; sometimes more damp, sometimes more dry. Viruses in particular cannot last very long outside of a host (length of time depends on the specific virus; researchers are still analyzing this factor for the COVID-19 virus). Toward that end, it’s a good plan to maintain the ideal range of relative humidity in your home. Will it help protect against the COVID-19 virus? We do not yet know. Will it help with your overall health and comfort? Yes, definitely. You can manage your home’s relative humidity with dehumidifiers and air conditioners, when possible. If you don’t have those systems, then air out your home when the external air is cool and dry.
Should I buy an indoor air filter for my home?
EPA research into various indoor filtration and cleaning solutions has found no effective solution for the residential market. This is in part due to the fact that residential equipment does not meet standards that could guarantee effectiveness of the products. Ultraviolet germicidal irradiation cleaners, photocatalytic oxidation cleaners, and ozone generators all proved ineffective in residential settings. High Efficiency Particulate Arrestor (HEPA) filters have the potential to remediate viruses. However, considering that the size of viruses are at the HEPA filter capture limit, the concern is that not all viruses will be captured or eradicated with the filter.
Regarding the COVID-19 virus, at this point, we don’t know enough to definitively prove that filtration will (or will not) work. It makes more sense to simply not let the virus enter your home. However, if you already own a filter, you can continue using it in order to keep the house clean of dust and allergen loads.
I’m exhausted from all of this worrying.
You are not alone. The COVID-19 pandemic is a lot for everyone to manage. Our generations have yet to live through something of this magnitude. Being worried and concerned is normal. The WHO has some great resources for mental health. It is important for all of us to remember that this too will pass, and we will move forward together. We may be physically distancing, but we are not socially distancing. Keep in contact with family and friends who may be having a harder time as well. Call or video conference with them and let them know that with some simple steps and processes, everyone can stay healthy and see this through.