Virus, bacteria or allergen? Cracking the case of the “crud”
- Joseph Rose, M.D., Medical Director
- April 14, 2025
When that tickle in your throat becomes a roaring case of “the crud,” you just want relief. However, knowing the cause of your coughing, sneezing, runny nose, or sore throat might be key to getting well. Let’s delve into the details of how viruses, bacterial infections and allergies affect you and what remedies might work for each. Then, stick around for some medical myth-busting!
Viruses
Going viral isn’t just for social media. Respiratory viruses, like colds, flu, COVID-19, and measles, are usually highly contagious. They survive by spreading in the environment (yes, measles is a respiratory virus). Respiratory viruses usually have symptoms like a cough, runny nose, sore throat, fever, headache, and body aches. Antibiotics, which fight bacteria, are of no use against viruses.
While the symptoms of mild viral illnesses can be handled with over-the-counter medications like acetaminophen, ibuprofen, and decongestants, you should consult your doctor if your symptoms worsen. If you or a loved one has shortness of breath, high fevers, severe fatigue, or confusion, seek medical assistance as soon as possible. Viral infections can turn into bacterial infections (colds can turn into pneumonia), so be on the lookout if your “crud” is trending worse after a few days instead of getting better .
The bottom line is that if your symptoms are mild, your illness probably is viral and will pass on its own. However, you may need to see your doctor if:
- Your symptoms get progressively more severe
- Your fever climbs too high (around 104° F)
- Your fever lasts too long (beyond 3-5 days)
Your provider can check to see whether you are developing pneumonia or maybe have a more serious condition – like the flu or COVID-19 – and prescribe the appropriate treatment.
Vaccines are available for many viruses, and while they don’t always keep you from getting ill, they often can reduce the symptoms. If you’re at high risk, you should consider getting your flu, pneumonia and COVID-19 vaccinations.
Who’s at risk? If you are pregnant, over age 65, have chronic lung or heart conditions or a compromised immune system, get immunized.
Bacterial infections
Bacterial infections are sometimes contagious, and some, like whooping cough, can be spread through droplets in the air. Other bacteria, like Streptococcus pyogenes (strep throat), can linger on surfaces or your skin. Bacterial infections can require treatment with antibiotics to get better. Because over-the-counter medications often don’t help bacterial symptoms, it is important to consult your doctor if you think an illness may be bacterial.
How do you know it’s bacterial? If your mild sniffling symptoms become more severe, you become short of breath, or you feel like a truck hit you and things aren’t improving, see your doctor. Make sure you’re not harboring pneumonia, bronchitis, or sinus infection. It is very important to see your physician if you are a high-risk patient.
Simple tests can determine if the cause is bacterial or viral. If the illness is bacterial, your doctor will know the best antibiotic to treat it. If you are prescribed an antibiotic, it is important to take all of it – even if you start to feel better – to prevent the bacteria from developing resistance to the medication.
Allergies
Allergies are not contagious because germs don’t cause them … but your body doesn’t know that. During an allergy attack, your immune system kicks into high gear to fight off an enemy. Only this time, the enemy isn’t a virus or bacteria; it’s a trigger, like pollen or pet dander. In its over-reaction, your body releases histamines, which cause symptoms like sneezing, itching, watery eyes and swelling. Mild allergies are similar to cold symptoms. But unlike viral colds, allergies usually resolve with over-the-counter antihistamines like diphenhydramine, loratadine and cetirizine (think Zyrtec or Allegra).
So, how can you tell the difference between allergies and infections? Allergies are often seasonal (think spring or summer). And allergies never cause a fever and typically don’t cause muscle or body aches.
See your doctor if over-the-counter medications don’t seem to work. Allergy testing to see exactly what is setting you off is available, and that knowledge might open the door to other possibilities to get relief. Also, if over-the-counter medications aren’t doing it for you, there are a host of prescriptions for allergies that may do better.
Prevention Tips
Preventing the spread of viruses, bacteria, and allergens can help keep you and your loved ones healthy. Here are some tips to consider:
- Wash your hands regularly: Use soap and water for at least 20 seconds, especially after being in public places, touching surfaces, or before eating.
- Avoid close contact with sick individuals: If someone around you is ill, try to maintain a safe distance to reduce the risk of infection.
- Cover your mouth and nose: Use a tissue or your elbow to cover coughs and sneezes and dispose of tissues properly.
- Clean and disinfect surfaces: Regularly clean frequently touched surfaces like doorknobs, light switches and phones.
- Stay home when you’re sick: If you’re feeling unwell, it’s best to stay home to prevent spreading the illness to others.
- Get vaccinated: Vaccines can help protect you from certain viral infections, such as the flu and COVID-19. If you are at high risk, make this a priority.
- Manage allergies: Keep windows closed during high-pollen seasons, use air purifiers, and regularly clean your home to reduce allergens. Consider wood, tile or laminate floors instead of carpet.
Debunking Myths
Now let’s tackle a few myths that many people believe:
Myth #1: You can only spread a cold if you have green mucus.
This is false. There are many ways you can and do spread illnesses. Colds and other viral infections spread through sneezes, coughs, and even talking. Even if you don’t have green mucus, you can still pass the virus to someone else. So, washing your hands regularly and covering your mouth when you cough is important.
Myth #2: Drastic weather changes make you sick.
Not true. While some people may feel under the weather when temperatures fluctuate, weather changes don’t cause illness. Instead, when the weather turns colder, people tend to stay indoors closer together, which can help germs spread more easily. According to the Centers for Disease Control and Prevention (CDC), the main culprits for getting sick are viruses and bacteria, not the weather.
Myth #3: You’ll always recognize the triggers if you have allergies.
This is also false. While some people know they’re allergic to pollen or pet dander, others might not realize what causes their symptoms. Environmental allergies can be sneaky! If you frequently have sneezing fits or itchy eyes, consider consulting an allergist for testing.
Learn more about allergies from Mark T. Jansen, M.D., Chief Medical Officer, here: Combating spring allergies with Arkansas Blue Cross and Blue Shield
Take Action
So, the next time you or someone you know feels sick, consider whether it’s a viral illness, bacterial infection or an allergy. And don’t fall for those common myths. If you’re unsure about your symptoms or how to treat them, contacting your primary care provider is always a good idea. If you don’t have one, you can connect to one by visiting the Blueprint Portal or calling the number on the back of your member ID card and speaking with one of our helpful customer service representatives.
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