Could Flu Be Causing Hives?

Following the recent Facebook post of a mother whose son experienced hives soon before being diagnosed with the flu, health experts are answering questions on whether the virus may have caused the child’s rash.

Individuals infected with the influenza virus typically experience symptoms including fever, chills, cough, sore throat, runny nose, body aches, headaches, and fatigue. While flu symptoms can come on suddenly and range in severity, most individuals who catch the flu typically recover within 2 weeks. The Centers for Disease Control and Prevention (CDC) says severe illness and flu-related complications resulting in hospitalization and death are most likely to occur in young children, adults age 65 and older, pregnant women, and those with chronic health conditions and compromised immune systems. Such complications can include severe pneumonia, inflammation of the heart or brain, sepsis, multi-organ failure, and sepsis.

The 2017-2018 flu season has been severe, largely due to the prevalence of the influenza A (H3N2) virus causing widespread flu activity across the entire continental United States. Overall, influenza A viruses have accounted for more than 81% of flu-positive respiratory specimens since the start of the flu season, and the CDC has reported 53 pediatric flu deaths through week 4. In light of that, a Facebook post from a Nebraska mother and nurse caught the attention of parents and public health specialists alike. In her post from January 26, 2017, Brodi Willard wrote that her 6-year-old son came home from school with hives that spread as the boy scratched them. When bathing the boy and changing his clothing did not alleviate the hives, his mother called their pediatrician, and found out that two other children who had visited the doctor that day with the same symptoms were diagnosed with influenza.

“I took him to the doctor this morning, and he tested POSITIVE for INFLUENZA B,” wrote Willard. “He has had NO symptoms. No fever, no cough, and no runny nose. He only has hives. Please keep watch on your children so if they develop hives, please call your pediatrician. I have never heard of this symptom but it is obviously something to be on the lookout for.” The literature on such cases is slim, though a 2014 study published in the journal Influenza and Other Respiratory Viruses details an influenza B outbreak in Canada in which 3 students at a rural school reported a localized rash.

William Schaffner, MD, medical director of the National Foundation for Infectious Diseases, and infectious disease specialist with Vanderbilt University School of Medicine says that since this case first made the news, he’s been contacted by 2 individuals reporting similar cases.

“I checked with my colleagues and none of us had ever seen anyone with influenza or any other respiratory viral illness that concurrently had hives associated with the illness,” said Dr. Shaffner in an interview with Contagion^®, noting the case was perhaps just an unusual coincidence. “Hives are not always a consequence of infections. In fact, I would think that they’re more likely to be an allergic reaction to something else that’s in the environment, but usually not too serious.”

He added that while influenza A viruses have caused the majority of flu illness this season, there have been recent reports of prevalent influenza B in areas of Texas and other parts of the country and that B viruses can have a late-season surge after A viruses start to wane.

“It’s possible that it is a rare event and in its rarity, is more associated with flu B rather than flu A, but it sure is unusual. Although the unusual is what catches our attention, it’s the more serious aspects of influenza that we ought to focus on,” said Dr. Shaffner, emphasizing that in this case, the child did not experience the typical and sometimes severe flu symptoms, such as fever or respiratory illness. “Although this is intriguing, it’s not serious, and I think that’s very important.”