Why is it important to wash your hands?
Washing your hands with soap is important because it reduces the spread of germs! People touch their eyes, nose, and mouth regularly, and that’s how germs can get into our bodies and make us sick. That’s why washing your hands can prevent yourself and others from spreading viruses like COVID-19!
The following demo will help you understand the science behind why washing your hands with soap and water is so effective!
Materials
- Aluminum foil
- Double-sided tape that stays sticky when wet
- Butter and butter knife
- Small plate
- Sprinkles (make sure they do not dissolve in water) or cracked pepper
- Bowl
- Warm water
- Paper towel
- Soap
- Spoon
Instructions
Prep
- Fill a bowl with warm water and add two squirts of hand soap.
- Mix the soapy water with a spoon until all the soap has dissolved.
- Pour a heap of sprinkles onto a small plate
Making the virus models
- Roll two balls out of the aluminum foil (½ inch diameter each)
- Cover each ball with double sided tape
- Roll one aluminum ball in the sprinkles
- Cover the second aluminum ball with butter and then cover it in sprinkles
Comparison and procedure
- Place both of your virus models next to each other. Which one do you think represents the enveloped virus and which one represents the non-enveloped one?
- Drop both the models into the bowl with the soapy water.
- Swirl the water with a spoon to make sure that the models get splashed with water from all sides. Observe for at least two minutes.
- After two minutes, take both aluminum balls out of the water and place them next to each other on a paper towel
Questions
- What do you think the aluminum ball represents in your virus model?
- What do you think the double-sided tape mimics?
- What do the sprinkles represent in your model?
- What does the butter mimic?
- What do you notice about the models over time as they were in the soapy water?
- Did the aluminum balls look the same once you took them out of the water?
Explanation
- We built two different virus models!
- One model represented a non-enveloped virus and the other was an enveloped virus like SARS-COV-2 (the coronavirus that causes COVID-19)
- Here is what each part represented:
- Aluminum foil = nucleic acid core that carries the genetic information of the virus in the form of RNA or DNA
- Double-sided tape = protein shell that protects the virus’s RNA or DNA
- Butter = lipid membrane that surrounds the protein shell of the viruses
- The fat in the butter is a similar type of lipid to the one found in virus envelopes. Only the enveloped virus had the butter because the non-enveloped virus does not have a lipid membrane.
- Sprinkles = proteins that a virus uses to attach to the outside of its host cell
- Non-enveloped virus has these proteins on the surface of the protein shell.
- Enveloped virus has these proteins on the surface of the lipid membrane
- Without these proteins, the virus cannot infect its host
- When you dropped the virus models into the water, it mimicked washing your hands with warm water and soap!
- The butter (lipid membrane envelope) slowly dissolved. This is because the soap molecules can interact and destroy the butter molecules. If that layer is destroyed, it should lose its sprinkles.
- The non-enveloped virus kept its sprinkles for a much longer time
- This means that washing your hands with soap can help make enveloped viruses (like COVID-19) noninfectious!