What Actually Is Enterovirus D68, and Why Are People Freaking Out About It?
We were starting to panic about Enterovirus D68, so we asked Vincent Racaniello, professor of microbiology and immunology at Columbia University to calm us down.
Astute watchers of American viral infections will likely have noticed a significant uptick in coverage of enterovirus D68 (EV-D68) over the past few weeks. The virus affects children more often than adults, and its symptoms are similar to a cold or the flu—fever, snotty nose, aching, coughing... The latest data from the CDC states that 780 people in 46 states and the District of Columbia are currently infected with it. That's more documented cases than in any other year, by a long shot. As the numbering of the virus implies, there are many different enteroviruses (several in the 'D' family alone) that fail to get the same coverage. Why might that be? Have infections increased as dramatically as the coverage would lead us to believe? Does it claim more victims than more well-known seasonal culprits, like the flu?
To find out, I spoke with Vincent Racaniello, professor of microbiology and immunology at Columbia University and also the proprietor of Virology blog, as well as several associated virology podcasts. His latest post on EV-D68 can be found here.
VICE: Hi, Professor Racaniello! What are the most common misconceptions about EV-D68?
Professor Racaniello: I guess the big one is that all of a sudden it popped up this year out of nowhere, and I don't think that's necessarily true. It's probably been around and we just haven't looked for it. The other one is that some people are worried that it may cause a polio-like paralysis. So there have been a cluster of cases in Colorado and a few others elsewhere where kids have gotten leg paralysis and they isolated from a few of them enterovirus 68. Again, you can't say that the virus caused the paralysis. I think it's probably just there coincidentally, but that's another thing the CDC is trying to figure out.
There's no medication or vaccine for EV-D68, correct?
That's correct. No antivirals, no vaccine. Just supportive therapy.
When you say "supportive therapy," what does that mean?
In most cases, it's a respiratory infection. It's pretty mild, like a common cold. Some kids, they get a more serious respiratory infection. They go to the hospital, they need breathing support. So oxygen, that's basically what we're talking about for the most seriously infected kids.
What is the typical outcome for someone infected with EV-D68? What kind of symptoms? Would most people even know they have it?
No, they couldn't distinguish it from a cold. They'd have sniffles, sore throat, runny nose, maybe a cough, mostly upper respiratory tract symptoms. They would just say "oh, I have a cold," and they wouldn't know it's enterovirus 68 at all. Now, in the case that it's much more serious and they can't breath and they're wheezing, their parents will notice this, of course, so they bring them to the hospital and then they get respiratory support. In those cases now we've been looking and then you find the virus.
I read that there is a quicker testing option available now?
Yeah, the CDC made a quicker test because they have a backlog of samples to get to so they'll be getting through that in the next couple of weeks. But now the thing is, we have a test for this specific "entero"—there are over 100 enteroviruses out there—so we're gonna be looking at this one and over-representing it because there are so many others we don't test for that we're never gonna know.
Is there a benefit to an earlier diagnosis or danger involved in being misdiagnosed?
I don't think there's any advantage to diagnosis of this infection because there's really nothing that we can do that's specific for this virus as opposed to any other that causes the same symptoms. Most people with this infection are going to be fine, they're going to recover in a week or two. And the kids who are really sick, they'll go to the hospital. Their parents will bring them if they have trouble breathing.
When do we typically start and end to see cases reported?
It usually starts at the end of the summer and it proceeds through the fall. By the end of the fall it starts tapering off. I would guess in the next month or so we're going to see a big decrease in the number of isolations for this virus.
Is this year's progression of the past few months typical? Are there really more new cases this year, or were they just undiagnosed in the past?
My guess is that we just never looked for it in the past. I think it's always been around. We discovered it in the 60s and it's probably been around since before then. You know, people get colds and they don't go to the hospital and so we don't know what's infecting them. I suspect enterovirus 68 has been circulating all over the world for years and years. This year in particular the CDC started looking for it and that's why I think we see so many isolations. But that doesn't mean there weren't as many infections as last year and the year before—we just didn't look for them. In fact, some people have been going back now to some stored samples from respiratory outbreaks and they find this virus in the US, in Asia, in Europe, in Africa... it's all over the place and it's been causing infections for many years. I think this thing this year is just a matter of us looking for it.
Are there any confirmed fatalities due to the virus?
They have five fatalities [This has now gone up to seven, per the CDC - Ed.]. They isolate the virus from those kids but we don't know if it caused their deaths.
Here's the headline on a Washington Post article about a recent Michigan case: "Michigan toddler dies after becoming infected with Enterovirus." Do you think that might give people the wrong idea about how conclusive the evidence is?
No, they absolutely cannot make any conclusions about causation. All they can say is he died after infection, but that doesn't mean the infection caused the death.
So as of right now, is there enough information available to be able to conclusively state that someone in the US has died of EV-D68?
My feeling is that this virus is circulating in a lot of people, so just by coincidence somebody who dies from some other reason could be infected by it. So you have to be really careful, you're just not sure if this is killing people.
Let's say they take one of these people from Dallas who's got Ebola and they die. And they found enterovirus 68. You wouldn't say that that caused their death, right?
That is a bit of a logical leap, yes.
The problem with these respiratory infections is that a common cold is so non-specific. It could be caused by many different viruses. And so it's really hard to point out the cause of death. But on the other hand, the Ebola patients, we know why they die and it's very specific to the virus.
Is there any credibility to the claims of certain right wing commentators that immigration is to blame for the increase in US cases?
No, that's nonsense. The virus has been all over the world and it has been for years.
What would you advise people to do to minimize their risk?
It would really help if our hand hygiene were better. Most of us don't pay attention to that. When you go into public places you really should wash your hands before touching your face, your eyes, your nose. But it's also probably spread by aerosols and there's not a lot you can do to them. I would just say be aware that your hand hygiene is the most important thing. I'd say any time you shake someone's hand, you touch a public place like a doorknob or some subway pole, just make sure that before you touch your hands to your face you go wash them so you're not going to transmit any microbes to your mucous membrane.
The virus most commonly affects children, correct?
Yes, and it's harder because they have even worse hygiene than adults. If you tell them to wash their hands that would do it. Now everyone's back in school so it's really hard with kids. Parents who have kids who are known to have asthma or any breathing difficulty just have to be vigilant. If they see evidence of an infection they have to get them to the doctor.
And if you suspect the child is sick, don't send them to school.
Certainly. Don't send them to school where they can infect other people. Absolutely.
Follow Simon Davis on Twitter.