These days, most people associate the phrase “going viral” with popular social media content and blog headlines. 2020 changed that. The coronavirus pandemic is hardly the way anyone wanted to have to familiarize themselves with the original concept of viral patterns. Still, it does have most people asking, “How do viruses spread?” More specifically, “How is the coronavirus transmitted, and how can I protect myself?”
What You Should Know About Viruses — A Quick Primer
All viruses are essentially the same: Their one function is to spread from host to host and then replicate using the host’s body. However, some viruses are more harmful than others and spread with more ease.
Viruses are a natural part of the world. There are good viruses that live as part of a healthy ecosystem, serving essential functions for their hosts. For example, some viruses have been used to treat dysentery, sepsis, salmonella and a variety of other bacterial infections for a century now.
In fact, an estimated 10% of human DNA is made of pieces of virus DNA. They are part of every human, contributing to positive immunity responses and shaping many human functions. For example, virus DNA is what allows humans to digest starches — pasta and bread lovers everywhere can thank their virus DNA.
Unfortunately, though, the world is well aware that there are also harmful viruses. They can cause a simple cold, a deadly flu strain or worse. The Zika virus, for example, was discovered in 1947, is transmitted by mosquitoes and causes congenital disabilities in the form of an underdeveloped brain. The Zika virus, like COVID-19, is relatively new in terms of virology discoveries and had to be studied before it could be understood, prevented and treated.
Where Did the COVID-19 Virus Come From?
There are several ways viruses generally spread. Some viruses are better at being transmitted through the air. Others use surfaces. Others use animals or insects as their carriers.
Viruses that spread from humans to animals or animals to humans are called zoonoses. There are approximately 1,700 known viruses, bacteria and other pathogens that infect humans. More than half of those originated in animals and crossed over to humans at some point. All other viruses come from environmental sources, such as air, water and soil.
Of the 37 new infectious diseases discovered in the past 30 years, more than two-thirds are from animals. Measles is an example of a virus that originated in domesticated animals. COVID-19 is also an example of zoonoses, originating from the unsanitary conditions of a “wet” market in China.
It’s important to note that while COVID-19 originated in animals in China and crossed to humans, there is currently no reliable evidence that animals, including pets and other domestic animals, can spread the virus to humans. In fact, in the very few cases of COVID-19 in cats and dogs, all of them were caused by a human who was already infected, not the other way around.
The best way to stay safe, should someone in the household become infected with the coronavirus, is to isolate them from everyone else in the household, including any pets.
How Do Viruses Spread?
While their sources may vary among animals, air, water and soil, viruses are transmitted similarly. This consistency in how viruses spread allows humans to anticipate risk factors and find meaningful ways to stay healthy and safe.
Airborne. Being carried in the air that people breathe is one of the most common ways that viruses spread. A human may sneeze or cough, releasing droplets of water that contain the virus into the air. The mucus membrane makes up the humans’ first line of defense against the outside world and is found in the nose, mouth and eyes. When humans breathe infected air, the virus comes into contact with the mucosal lining, infecting them.
Not all viruses are airborne, but COVID-19 is considered airborne in the sense that it can travel through droplets of water in the air to infect others. The best way to avoid this transmission method is only possible if people adequately cover their mouths when sneezing or coughing, use correctly fitted masks and face shields, and keep a safe distance from people who may be infected. To avoid COVID-19, it’s currently recommended that people keep at least 6 feet of distance from people who could be infected.
Foodborne. Drinking and eating are also common ways that bacteria, parasites, and viruses spread. While access to clean drinking water, washing produce before cooking, and properly preparing and cooking food are the best ways to avoid foodborne illnesses, this transmission method is widespread throughout the world, including First World fine-dining establishments.
Something as simple as not washing hands thoroughly enough before cooking or serving food can lead to deadly outcomes. The best way to stay safe from foodborne illnesses is to only patronize well-established, clean restaurants, if any.
Be sure you know how your food is being prepared and cooked, including whether everyone is not only washing their hands but washing their hands properly. The CDC has linked COVID-19 to dining out, indicating that those who eat out are twice as likely to contract the disease as those who have their meals at home. That means dining out should be avoided for those who want to reduce the likelihood of contracting COVID-19. When dining at home, always wash produce correctly and use other cooking best practices, such as thoroughly cooking meat, keeping it separate from other food, and never placing cooked meat back on surfaces that were used to prepare it.
Bloodborne. Pathogens that are bloodborne must be exposed to the body’s mucosal lining, or occur when someone else’s blood mixes with your blood in your body, such as from an open cut or using an unsanitary syringe. Hepatitis, HIV and a variety of sexually transmitted diseases are all considered the results of bloodborne pathogens.
At this time, there is no evidence, data or cases of bloodborne transmission of COVID-19. While it can live in the blood, COVID-19 is a respiratory disease, not a bloodborne pathogen. This is why it is still considered safe to donate blood, even during the coronavirus pandemic. To avoid other bloodborne pathogens, always practice safe sex, never share or reuse syringes, use gloves if you are handling high-risk items and have open cuts on your hands, and always wash your hands properly and thoroughly.
Surfaces. While viruses have differing lengths of life on various surfaces, these are a common point of transmission. Hepatitis C, for example, can live as long as three weeks on a variety of surfaces. HIV, however, may only live for seconds outside the body.
COVID-19 is primarily transmitted through the air and can be transmitted via food. However, the virus may also spread by touching a surface with the virus on it and then touching your face, nose, mouth or eyes. The best way to avoid this form of transmission is to maintain good sanitation and wash surfaces often; wash your hands often and adequately; and not touch your face, unless you just washed your hands.
A few best practices to keep in mind: Anytime you go out or someone comes to your home, make sure you wear a mask. Additionally, when it’s safe to remove your mask, don’t touch the inside of it to avoid spreading the virus to the surface that touches your face. Finally, always wash and sanitize your hands after touching your mask.
How Is the Coronavirus Transmitted, and How Can People Stay Safe?
At this time, it is understood that COVID-19 is primarily transmitted by droplets of water in the air from an infected person entering your nose, mouth or eyes. This means wearing a properly fitted face mask and face shield, social distancing, and washing your hands are all vital to staying safe.
COVID-19 can also be transmitted by food. Although this risk is considered low, people who dine out are twice as likely to become infected. Always use best practices when cooking and avoid dining out until better safeguards can be identified and put in place to avoid transmission at dining establishments.
The coronavirus is not bloodborne, which is why it is still safe and vital to donate blood, if possible. However, the virus can be spread by touching surfaces and then touching your face. Wearing a mask can help you get into the habit of not touching your face. Also, remember to wash your hands and surfaces properly and often, and use an alcohol-based hand sanitizer when on the go.
By understanding that some viruses can create higher risk in some forms than others, and by always building best safety practices and basic sanitation into everyday routines, you can protect yourself and your loved ones from infections of all types, including the coronavirus.
References
https://www.sciencedaily.com/releases/2016/11/161128151050.htm
https://www.cdc.gov/zika/healtheffects/birth_defects.html
https://www.who.int/news-room/fact-sheets/detail/zika-virus
https://www.nationalgeographic.com/animals/2020/04/coronavirus-linked-to-chinese-wet-markets/
https://www.healthline.com/health/airborne-diseases#types
https://www.news-medical.net/health/What-are-Foodborne-Viruses.aspx
https://www.cnn.com/2020/09/10/health/restaurant-dining-covid-19-cdc-study-wellness/index.html
https://www.cdc.gov/nora/councils/hcsa/stopsticks/bloodborne.html
https://www.redcross.org/about-us/news-and-events/press-release/2020/red-cross-media-statement-on-2019-novel-coronavirus.html