It’s the final week of Rock the Walk, so buckle up. We’re going to talk about viruses and bacteria. Understanding and appreciating our tiny friends can help make sense of the latest infection control recommendations. When it comes to your immunity, doing your part to keep germs away means your immune system has less work to do.
Normally, things like “epidemiology” and “viral transmission” are not part of our everyday conversation. Enter 2020.
Public health practitioners have been talking about superbugs and infection control for years. Since 1901, when the virus responsible for yellow fever was discovered, scientists have identified around 250 viruses that are known to infect humans. If that sounds overwhelming, consider this. There are an estimated 10 nonillion viruses that exist in nature (that’s 1 followed by 30 zeros). That’s a lot of viruses. But, so far, only around 250 of those are capable of making you sick.
Viruses aren’t the only things that can infect you. Bacteria, fungi (such as ringworm), protozoa (such as dysentery), and helminths (parasitic worms like hookworm) are other culprits. All of them work differently, spread differently and have different biological requirements to reproduce. That’s why an antibiotic will work on a bacterial infection but not on a viral infection. And one antibiotic, like penicillin, is effective in treating some bacterial infections, but not all.
Today, we’ll focus on how viruses and bacteria make you sick. But, if you’re interested in learning more about fungi, protozoa, or helminths (because who doesn’t like a good tapeworm story), go to cdc.gov/parasites.
Since not all bacteria and viruses cause problems for humans, we’ll call the ones that make you sick “germs.” If you don’t study germs for a living, it might seem inconsistent or confusing when scientists and medical providers tell you different things to do to protect yourself against infection. For example, why are masks important now, but they weren’t for last year’s flu season? The answer lies in what specific germs need to infect you, reproduce and jump to a new host, so they survive.
Take Botulism. The botulism bacteria, Clostridium botulinum, doesn’t make people sick on its own. When it has the right conditions to grow, it produces a toxin. The toxin makes you sick. If Clostridium botulinum isn’t allowed to grow, then it can’t produce the toxin. Wearing a mask will not protect you from botulism; preparing, storing and heating your food properly will.
That’s why during a botulism outbreak, the CDC recommends disposing of the contaminated food rather than wearing a mask.
Generally speaking, viruses are very tiny packets of genetic material. They don’t have the capacity to reproduce until they enter a host, so they sit dormant, waiting for a compatible host. Once they are in a host cell, the virus uses the cell’s machinery to multiply.
Viruses are responsible for illnesses and diseases such as measles, chickenpox, AIDS, SARS, the common cold, flu and COVID-19.
Bacteria are more self-sufficient. They have what they need to multiply. Each bacteria has different growing requirements in terms of the food they need, their ideal temperature range for reproduction, whether they need water, oxygen or acidic conditions, etc. Much of what you do with food preparation and storage is manipulating growing conditions to stop bacteria (and other microbes) from ruining your food or making you sick.
Bacteria are responsible for infections such as strep throat, staph infections, urinary tract infections and tuberculosis.
For germs to infect you, they have to get past your skin. (three cheers for skin!) For the most part, germs can sit on your skin without hurting you; until they find a way into your body, they won’t be able to do much to you. That said, your mouth, nose, eyes, urogenital openings, and wounds all offer access because, well, they are not covered by skin.
But that’s not the whole story. The way a germ spreads matters too. Here are the most common modes of transmission for germs:
Germs can infect you in more than one way. For example, you can get chickenpox through direct contact or through airborne transmission.
Why do we really need to protect ourselves from germs? There are a few reasons. Continuing with chickenpox as an example, you may have survived chickenpox. But, there’s no way to know how severe a case will be. People still die from chickenpox.
Let’s be honest. You may have survived chickenpox, but it wasn’t fun, you probably missed a lot of school and it probably left scars. Would you choose to have it if you could choose not to? Vaccines allow you to build immunity without experiencing the illness firsthand, so you get the immunological benefit of having the virus without actually having the virus.
Here’s another reason to avoid getting sick when possible. When you get a vaccine or protect yourself from exposure, you help stop the spread of germs so that people who cannot get vaccinated or take antibiotics are much less likely to be exposed to the illnesses to begin with.
And, remember, germs need to multiply to keep spreading. If a virus makes it into your system and your immune system stops it, it can’t move on to another person.
There’s no one way to prevent infection. There are a lot of infections out there. They all spread differently and require different prevention strategies.
When it comes to prevention, it’s best to practice everyday strategies that protect you against most germs. Then, when there is a specific illness causing concerns, expand the list as needed.
Right now, keeping your distance from others and wearing a mask are important precautions to add to the list in order to stop the spread of COVID-19. Remember: germs need you in order to multiply and spread. Using general prevention strategies every day helps protect you and keeps germs from spreading to others in your family and community.
Here are a few healthy habits that will help you fight the majority of infections:
To learn more about how your immune system fights germs and how vaccines boost your immune system, try these resources: