Public health experts are cautioning that the coming flu season could complicate attempts to diagnose new cases of a mysterious vaping-related illness — and, in turn, make it more difficult to track down the cause.
The issue, experts say, is that flu and other respiratory viruses can, in many ways, look strikingly similar to a case of vaping-related illness: Symptoms include shortness of breath, night sweats, low oxygen levels, and hazy spots on a lung X-ray.
“It’s going to be difficult to tease apart a bad flu case and a vaping case,” said Dr. Sean Callahan, a University of Utah Health pulmonologist who has treated several cases of vaping-related illness.
Under the current guidelines from the Centers for Disease Control and Prevention, doctors are expected to rule out flu or any other infectious cause of illness before diagnosing a case of vaping-related illness. But as winter nears, it’s increasingly possible that people who vape heavily will also start testing positive for flu or another respiratory infection. As a result, the agency may be forced to reconsider its definition of vaping-related illness, experts said.
The CDC, when asked, didn’t respond directly to the question of whether its definition might need to be revised.
The flu season “makes the entire business more complicated,” said Dr. Jeff Duchin, a public health official in Seattle and King County and an infectious diseases professor at the University of Washington.
Just a few months ago, an otherwise healthy young patient coming into the hospital complaining of difficulty breathing, a cough, or night sweats would be suspected as having the flu or pneumonia. Opaque spots on an X-ray, too, would add to that suspicion. But this summer, that assumption started to shift as health officials sounded an alarm about the symptoms of vaping-related illness. There have been 805 confirmed and probable cases of the illness as of Tuesday.
Now, as flu cases become more common, doctors will increasingly have to juggle both possibilities. Both vaping-related illness and severe cases of the flu can become life-threatening if untreated.
“You can be hospitalized because of complications of the flu, because of e-cigarette use unrelated to the flu, or a combination of the two,” Duchin said.
That combination is of particular concern, because flu or other viruses could exacerbate the symptoms of vaping-related illness. If patients already have compromised lungs and then develop a viral infection, they may become sicker. And what happens if a positive test for a virus means a missed diagnosis of vaping-related illness?
“[Vaping-related illness] can be missed if the physician is not looking for it, absolutely. If you do not address it, the patients may get very sick,” said Dr. Melodi Pirzada, a pediatric pulmonologist with NYU Langone Health who has treated several cases of vaping-related illness.
Pirzada has already seen it happen. She is currently treating a young man who initially went to an outpatient clinic with cough, shortness of breath, and a fever. His scans showed hazy spots on the lungs. He tested positive for an infectious bacteria called Mycoplasma pneumoniae. He was started on antibiotics and sent home.
But instead of feeling better after finishing the course of antibiotics, he grew more ill. He was far sicker than a normal patient with this kind of infection, particularly one who didn’t have an especially severe infection, Pirzada said. Last week, the patient was admitted to the hospital. Pirzada discovered that he had vaped THC daily for more than a year. After several days on steroids — part of the standard treatment for vaping-related illness — his condition improved.
Pirzada is convinced it is a case of vaping-related illness, complicated and concealed by an infection.
“We see tons of patients with Mycoplasma infection, and this is not the norm for that,” she said.
A CDC spokesperson told STAT that during flu season, the agency recommends considering both respiratory infections and vaping-related illness in patients with both respiratory problems and a history of e-cigarette use. Since it might not be possible for doctors to definitively determine the cause, it might be necessary to treat patients for both conditions.
Experts said the overlapping illnesses likely won’t complicate influenza surveillance, as patients will still be tested for flu. But it will make it harder to accurately track cases of vaping-related illness, a critical step in the effort to get the outbreak under control.
Duchin said the vaping-related illnesses are another reason to get a flu shot this season, noting that flu shots could be part of the public health messaging around vaping risks. But others said they’d like to see a culprit or culprits identified by the time flu season is in full swing.
“My hope is that whatever this is is gone by the time flu season picks up,” Callahan said.