Flu season is coming to an endAnd weekly COVID-19 diagnoses are in decline. But if you are currently suffering from a respiratory illness, you are not alone.
Data from the United States Centers for Disease Control and Prevention (CDC) shows that a mix of respiratory viruses are currently circulating, including common coronaviruses (other than SARS-CoV-2, which causes COVID-19), adenoviruses respiratory and parainfluenza (which differs from the flu).
All of these viruses can cause cold-like symptoms, including fever, runny nose, sore throat and cough, so it’s “very, very difficult to tell the difference between any of them.” clinically,” says Dr. Helen Chu, associate professor of infectious diseases at the University of Washington and principal investigator at the Seattle Flu Alliance, which tracks the spread of respiratory disease. (Norovirus and rotavirus are also circulating at this time, but they cause gastrointestinal problems such as vomiting and diarrhea.)
While many viruses are spreading right now, one respiratory virus is currently causing a particularly high percentage of positive results among test results tracked by the CDC: human metapneumovirus (HMPV). More than 20% of antigens and 10% of PCR tests voluntarily reported to the CDC by US labs during the week of March 11 came back positive, agency data shows. “It is important to note that this is expected respiratory activity for these viruses for this time of year,” a CDC representative told TIME, noting that the agency is also tracking increases in adenovirus and parainfluenza.
Dr. John Williams, who is chief of infectious diseases at UPMC Children’s Hospital in Pittsburgh and has studied HMPV for more than 20 years, agrees that a slight increase in HMPV is not surprising. In North America, peak HMPV season is usually February through May, a little after typical flu season, he says.
This season, “we saw a higher than normal RSV surge And larger than normal flu flare“, explains Williams. “Knowing the seasonality of metapneumovirus, I said, ‘I bet we’re going to see a similar surge of metapneumovirus. And, in fact, we are.
Many people have probably had HMPV without ever knowing what it was, as it usually causes familiar cold-like symptoms like cough, fever, and stuffy nose. In severe cases, which are more common in young children and older or immunocompromised adults, HMPV can also lead to complications such as bronchitis and pneumonia, according to the CDC. Some people also suffer from shortness of breath.
It’s hard to say if this year’s HMPV season is worse than usual, says Dr. Ann Falsey, a professor of medicine at the University of Rochester Medical School, because “we’re testing a lot more now. People are very keen to get a swab” after three years of the pandemic.
Still, many cases of HMPV likely go undetected, Williams says. Today, clinicians routinely test for SARS-CoV-2, influenza, or RSV if they see a patient with respiratory illness. Some tests can detect HMPV, but they tend to be expensive and used less frequently.
Researchers won’t fully understand how widely viruses like HMPV spread without broader testing, Falsey says. And if doctors don’t know why a patient is sick, they may prescribe antibiotics unnecessarily, she says, which can contribute to antibiotic resistance.
But Chu says it’s not always necessary for patients to know exactly what disease they have. It is useful to test for SARS-CoV-2 and influenza because there are treatments for these conditions, Chu said. Screening for RSV also makes sense because it can cause serious illness, especially in young children. But if those viruses have been ruled out, Chu says there’s usually no need for further testing because there are no specific treatments for HMPV and many other respiratory viruses that circulate during a normal cold season and flu.
Williams says there may be vaccines and treatments for more respiratory viruses in the future. But if you currently have an unknown condition, follow some proven advice: rest welltake over-the-counter medications for your symptoms, see a doctor if they get worse, and stay home to avoid infecting anyone else.
And, says Falsey, remember that many of the disease prevention tactics used during the pandemic can work against other viruses, Also. “Now that we’re all in circulation again, all these different viruses will attack us again,” she says. “If you’re particularly frail or have underlying medical conditions, we’ve learned that masking works if you’re in a crowded place.”
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