When it finally gets here, the fall will bring cooler temperatures, and the usual seasonal illnesses — flu, RSV in kids, COVID, strep and, of course, the common cold.
KERA's Sam Baker talks with Dr. Donna Casey, an internist with Texas Health Dallas, about why this happens.
Dr. Casey: The biggest one is behavioral shifts, which means people are now going back to school, they're gathering in workplaces.
Obviously, children serve as a primary vector, right? When kids go to school they congregate and they spread germs because they don't really have the best hygiene behavior and then they spread it to their families and then it just spreads from there.
When the temperature does go down, viral droplets, respiratory droplets, live longer in colder, drier air. So that's not a problem right now but it will become October.
Baker: Has the triple-digit heat impacted this one way or another.?
Dr. Casey: Yeah, it's probably helped us.
And then we also know now that sunlight helps your body make vitamin D. And when your vitamin D is low, your immune system doesn't work as well. So that's not a problem for us right now, but it will become November, December, January when people have less vitamin D. Which is why we, in my office, we check everyone's vitamin D level and we supplement vitamin D.
Baker: Do these common illnesses have common symptoms?
Dr. Casey: You know, the flu is pretty black and white. You'll be driving down your road and you're like, hey, I suddenly have a high fever and body aches. It's like, boom, that's the flu.
Other things like respiratory syncytial virus (RSV) is just kind of like a runny nose. And you think, oh, maybe I've got allergies.
COVID and strep are more like a sore throat, fever. You're kind of a little cough and lymph nodes in your neck.
And a lot of confusion comes in Dallas because of allergies, right? Ragweed, mold, pollen. People think, Oh, I just have a little runny because there's something in the air, right?
Then they go take a Sudafed or a decongestant or antihistamine. And I think that the differentiating factor is really a low grade fever or feeling like I really just need to go take a nap or get in bed or go to bed early.
Baker: What among these common illnesses is really spreading now in particular?
Dr. Casey: We're seeing a lot of COVID right now. People do not want to check for COVID because COVID has kind of a scary feel to it. And when I ask patients to check, they say, I absolutely won't do it.
Baker: They won't do it?
Dr. Casey: They really won't, because they are like, then I'm going to have to take off work.
The current COVID is more of a common cold type thing where people are just having like a few days of fatigue and runny nose and then they get over it and kind of forget about it and they think, oh, I just had like some allergies.
But my concern is the vulnerable population. I'm going to get a flu shot because I don't want to give my dad the flu or somebody who's immunocompromised. The last thing we want is for an immunocompromised person to get sick.
The reason is not because of the upper respiratory infection. The reason is, when people who are immunocompromised get sick, you have this inflammatory cascade that happens in your body. You release all these proteins.
It's like your army gets ready to fight, and you release, for instance, tumor necrosis factor and IL-6 and fibrinogen , and that's to go fight the invader, right?
But the problem is that makes all of your blood vessels inflamed. It makes your blood thick, which means clots or strokes. So when you do get the flu, you've a six times higher risk of having a heart attack. Even if you don't have horrible blockages. We know that inflammatory cascade makes your heart blood vessels sticky and inflamed.
So they start releasing, for instance, if you have a little plaque, little, little cholesterol plaques, which could be heart attack, stroke. If you have any cognitive issues, like low grade dementia, it can make it worse.
That is more of my concern with getting a flu. It's not that somebody has a cough and a cold and they get over it or miss a few days of work.
My point is a lot of people are out driving around and living their lives and not realizing that they're vulnerable. And they're like, thinking just the flu is not that big of a deal or if I have a common cold, it's not a big deal.
But we really worry about people being vulnerable and they've increased risk of heart attack, stroke, kidney disease, dementia, any vascular issue in this populations that get any of these viruses or strep throat.
Baker: What should you do to prevent these kind of illness?
Dr. Casey: Obviously, a flu vaccine. If you are vulnerable, you probably should get a COVID vaccine. And then there's a new respiratory syncytial virus vaccine — an RSV vaccine — available at any pharmacy, at any grocery store.
But the most important thing also is I think everybody should have a primary care physician.
RESOURCES:
Common Illnesses To Watch Out For In September
CDC: Other Respiratory Illnesses Going Around
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