How Does UV Disinfection Kill Viruses and Bacteria?

With more and more ultraviolet (UV) disinfection products emerging on the market, people’s questions and concerns are rising, too. How does UV technology kill viruses and bacteria? Is UV disinfection effective? Are UV light products worth trying?

Let’s dig in and answer the most common questions about UV light and UV disinfection that you may have.

What Is UV Light?

Since its discovery in the late 1800s, ultraviolet light has been the go-to solution for disinfection and sanitation. Due to its non-toxic nature and effective results, many industries have embraced UV light. This includes hospitals, water treatment plants, and food manufacturing sectors. It is a known disinfectant for air, water, and nonporous surfaces.

To get a little technical, UV light refers to a range of electromagnetic waves. They have shorter wavelength but a higher frequency and energetic radiation than the visible ultraviolet light.

There are three distinct kinds of ultraviolet light: UV-A, UV-B, and UV-C. It’s a common misconception that all three do the same thing. While natural sunlight consists of all three types of UV rays, each band varies in wavelength, characteristics, range. They differ in how much they can penetrate surfaces, including the skin.

UV-C rays or germicidal UV light (UVGI) have the shortest wavelength and, therefore, possess the highest radiation. For UV disinfection, only this band has the power and the ability required to kill bacteria, mold, viruses, and fungi effectively.

In recent years, UV-C light has played a vital role in stopping the spread of numerous pathogens like the superbug and the flu.

So, if you’re shopping for UV disinfection products, make sure that their wavelength falls in the range of UV-C light. It is between 200 nm to 280 nm. However, keep in mind that the intensity of the UV-C rays in this range differs, too.

So, How Does UV Disinfection Work?

To understand how UV-C light kills viruses and bacteria, we need to have a basic understanding of their DNA and RNA structure. Like all living microorganisms, bacteria and viruses store instructions on reproduction, growth, functioning, and development in their DNA and RNA.

The Difference Between DNA and RNA

DNA modules are made of two strands bound together by four bases – adenine, cytosine, guanine, and thymine. On the other hand, RNA modules are single-stranded and bound by nitrogenous bases called adenine, guanine, cytosine, and uracil, which replace thymine in DNA.

DNA strands carry the genetic information of living organisms, such as humans, whereas RNA can take on multiple roles. Due to the structure of RNA molecules, they can be continuously broken down, made, and reused. This allows the organisms that possess them to mutate.

Living organisms that need to rapidly change in order to survive use RNA as a basis of their genetic structure. Viruses such as influenza (the common flu), HIV, and the novel COVID-19 have RNA. Therefore, they are able to remain one step ahead of our immune system. Since the structure of these viruses keeps changing, they can reinfect us even if we’ve already had the disease they carry.

How Does UV Light Destroy DNA and RNA?

What UV light does is cause thymine or cytosine bases in DNA and uracil dimers in RNA to fuse together. This scrambles and changes the structure of DNA, RNA, and proteins in bacteria and viruses.

Since the DNA and RNA sequences are no longer correct, bacteria and viruses can not replicate correctly. As a result, their ability to reproduce through cell division is destroyed, and they are no longer infectious.

Keep in mind that RNA can mutate. Therefore, it is more resistant to UV light damage than DNA. It doesn’t mean that RNA is immune to UV-C light though. When used correctly, UV cleaning products can effectively inactivate it.

This is because the effectiveness of UV light disinfection depends on various factors. These factors include the radiation power applied, the length of exposure time, and the distance from the light source.

Having said that, studies confirm that UV-C light has the right properties to kill 99.99% of all bacteria and viruses. This reduces the likelihood of a disease outbreak.

The Advantages of UV Disinfection

There are many benefits of using UV disinfection, but below the top two are highlighted:

1. High Pathogen Kill Rate

As mentioned above, research has proved that germicidal UV light kills up to 99.99% of bacteria and viruses. The best part? UV light kills all kinds of pathogens regardless of their drug resistance! One again, only if used correctly.

2. Zero Chemical Exposure

UV disinfection is a non-chemical and toxic-free method of disinfection. It’s environmentally friendly and requires low maintenance.

Due to its efficient and toxic-free approach of disinfection, UV light disinfection is gaining acceptance in many sensitive industries. This includes the food and beverage sector. That’s because it kills all known pathogenic and food spoilage microorganisms effectively and quickly.

This means that you no longer need to use bleach to strip your groceries off of bacteria, viruses, or any other pathogens! UV light can also effectively destroy pathogens in the germy areas of your house that you may not be aware of.

Precautions When Using UV Disinfection Devices

In recent years, many UV cleaning products have become available to consumers to disinfect everything from mobile phones to toothbrushes. They come in various forms, including wands, boxes, and bottles. Each of them has its own manual of instructions on how to use the light to kill germs. These instructions should include specifics on light source distance and exposure time.

It’s important to read and follow these instructions. That’s because despite the significant benefits of UV light disinfection, it has one major drawback. Since it can destroy DNA, UV light can be harmful to humans if used incorrectly. If you don’t use protective equipment during the application of UV light, it can cause health issues such as skin cancer and cataract.

In addition to the above, not all UV light cleansers are the same. Most low-cost UV wands are low in potency. Therefore, you may be able to look at or be in the same room with them. This, however, means that they are not as effective as you may expect. They will require a longer exposure time to kill viruses and bacteria as efficiently as stronger UV light disinfection devices would be able to do it in seconds.

By combining the safety features and the strengths of UV-C wavelength, Wolven’s UV light cleanser maximizes the intensity of bacteria-killing light delivered. Don’t just wash your hands, prevent yourself from exposure to bacteria and viruses in the first place!